feat: Add RegexPatternUtils for centralized regex management, file naming funcs, UtilityClass annotation (#4218)

Co-authored-by: Copilot <[email protected]>
Co-authored-by: Anthony Stirling <[email protected]>

app/common/src/main/java/stirling/software/common/service/JobExecutorService.java

@@ -22,6 +22,7 @@ import lombok.extern.slf4j.Slf4j;
 
 import stirling.software.common.model.job.JobResponse;
 import stirling.software.common.util.ExecutorFactory;
+import stirling.software.common.util.RegexPatternUtils;
 
 /** Service for executing jobs asynchronously or synchronously */
 @Service
@@ -426,8 +427,16 @@ public class JobExecutorService {
         }
 
         try {
-            String value = timeout.replaceAll("[^\\d.]", "");
+            String value =
-            String unit = timeout.replaceAll("[\\d.]", "");
+                    RegexPatternUtils.getInstance()
+                            .getNonDigitDotPattern()
+                            .matcher(timeout)
+                            .replaceAll("");
+            String unit =
+                    RegexPatternUtils.getInstance()
+                            .getDigitDotPattern()
+                            .matcher(timeout)
+                            .replaceAll("");
 
             double numericValue = Double.parseDouble(value);
 

app/common/src/main/java/stirling/software/common/service/SsrfProtectionService.java

@@ -13,6 +13,7 @@ import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
 
 import stirling.software.common.model.ApplicationProperties;
+import stirling.software.common.util.RegexPatternUtils;
 
 @Service
 @RequiredArgsConstructor
@@ -22,8 +23,9 @@ public class SsrfProtectionService {
     private final ApplicationProperties applicationProperties;
 
     private static final Pattern DATA_URL_PATTERN =
-            Pattern.compile("^data:.*", Pattern.CASE_INSENSITIVE);
+            RegexPatternUtils.getInstance().getPattern("^data:.*", Pattern.CASE_INSENSITIVE);
-    private static final Pattern FRAGMENT_PATTERN = Pattern.compile("^#.*");
+    private static final Pattern FRAGMENT_PATTERN =
+            RegexPatternUtils.getInstance().getPattern("^#.*");
 
     public enum SsrfProtectionLevel {
         OFF, // No SSRF protection - allows all URLs

app/common/src/main/java/stirling/software/common/service/TempFileCleanupService.java

@@ -23,6 +23,7 @@ import lombok.extern.slf4j.Slf4j;
 
 import stirling.software.common.model.ApplicationProperties;
 import stirling.software.common.util.GeneralUtils;
+import stirling.software.common.util.RegexPatternUtils;
 import stirling.software.common.util.TempFileManager;
 import stirling.software.common.util.TempFileRegistry;
 
@@ -61,8 +62,14 @@ public class TempFileCleanupService {
     // File patterns that identify common system temp files
     private static final Predicate<String> IS_SYSTEM_TEMP_FILE =
             fileName ->
-                    fileName.matches("lu\\d+[a-z0-9]*\\.tmp")
+                    RegexPatternUtils.getInstance()
-                            || fileName.matches("ocr_process\\d+")
+                                    .getSystemTempFile1Pattern()
+                                    .matcher(fileName)
+                                    .matches()
+                            || RegexPatternUtils.getInstance()
+                                    .getSystemTempFile2Pattern()
+                                    .matcher(fileName)
+                                    .matches()
                             || (fileName.startsWith("tmp") && !fileName.contains("jetty"))
                             || fileName.startsWith("OSL_PIPE_")
                             || (fileName.endsWith(".tmp") && !fileName.contains("jetty"));

app/common/src/main/java/stirling/software/common/util/EmlParser.java

@@ -29,7 +29,7 @@ public class EmlParser {
     private static volatile boolean mimeUtilityChecked = false;
 
     private static final Pattern MIME_ENCODED_PATTERN =
-            Pattern.compile("=\\?([^?]+)\\?([BbQq])\\?([^?]*)\\?=");
+            RegexPatternUtils.getInstance().getMimeEncodedWordPattern();
 
     private static final String DISPOSITION_ATTACHMENT = "attachment";
     private static final String TEXT_PLAIN = MediaType.TEXT_PLAIN_VALUE;
@@ -357,7 +357,11 @@ public class EmlParser {
                     for (String contentIdHeader : contentIdHeaders) {
                         if (contentIdHeader != null && !contentIdHeader.trim().isEmpty()) {
                             attachment.setEmbedded(true);
-                            String contentId = contentIdHeader.trim().replaceAll("[<>]", "");
+                            String contentId =
+                                    RegexPatternUtils.getInstance()
+                                            .getAngleBracketsPattern()
+                                            .matcher(contentIdHeader.trim())
+                                            .replaceAll("");
                             attachment.setContentId(contentId);
                             break;
                         }
@@ -414,7 +418,8 @@ public class EmlParser {
 
     private static String extractBasicHeader(String emlContent, String headerName) {
         try {
-            String[] lines = emlContent.split("\r?\n");
+            String[] lines =
+                    RegexPatternUtils.getInstance().getNewlineSplitPattern().split(emlContent);
             for (int i = 0; i < lines.length; i++) {
                 String line = lines[i];
                 if (line.toLowerCase().startsWith(headerName.toLowerCase())) {
@@ -485,7 +490,10 @@ public class EmlParser {
     }
 
     private static int findPartEnd(String content, int start) {
-        String[] lines = content.substring(start).split("\r?\n");
+        String[] lines =
+                RegexPatternUtils.getInstance()
+                        .getNewlineSplitPattern()
+                        .split(content.substring(start));
         StringBuilder result = new StringBuilder();
 
         for (String line : lines) {
@@ -499,7 +507,8 @@ public class EmlParser {
     private static List<EmailAttachment> extractAttachmentsBasic(String emlContent) {
         List<EmailAttachment> attachments = new ArrayList<>();
         try {
-            String[] lines = emlContent.split("\r?\n");
+            String[] lines =
+                    RegexPatternUtils.getInstance().getNewlineSplitPattern().split(emlContent);
             boolean inHeaders = true;
             String currentContentType = "";
             String currentDisposition = "";
@@ -562,7 +571,11 @@ public class EmlParser {
             if (filenameStarEnd == -1) filenameStarEnd = disposition.length();
             String extendedFilename =
                     disposition.substring(filenameStarStart, filenameStarEnd).trim();
-            extendedFilename = extendedFilename.replaceAll("^\"|\"$", "");
+            extendedFilename =
+                    RegexPatternUtils.getInstance()
+                            .getQuotesRemovalPattern()
+                            .matcher(extendedFilename)
+                            .replaceAll("");
 
             if (extendedFilename.contains("'")) {
                 String[] parts = extendedFilename.split("'", 3);
@@ -577,7 +590,11 @@ public class EmlParser {
         int filenameEnd = disposition.indexOf(";", filenameStart);
         if (filenameEnd == -1) filenameEnd = disposition.length();
         String filename = disposition.substring(filenameStart, filenameEnd).trim();
-        filename = filename.replaceAll("^\"|\"$", "");
+        filename =
+                RegexPatternUtils.getInstance()
+                        .getQuotesRemovalPattern()
+                        .matcher(filename)
+                        .replaceAll("");
         return safeMimeDecode(filename);
     }
 
@@ -630,11 +647,23 @@ public class EmlParser {
         private List<EmailAttachment> attachments = new ArrayList<>();
 
         public void setHtmlBody(String htmlBody) {
-            this.htmlBody = htmlBody != null ? htmlBody.replaceAll("\r", "") : null;
+            this.htmlBody =
+                    htmlBody != null
+                            ? RegexPatternUtils.getInstance()
+                                    .getCarriageReturnPattern()
+                                    .matcher(htmlBody)
+                                    .replaceAll("")
+                            : null;
         }
 
         public void setTextBody(String textBody) {
-            this.textBody = textBody != null ? textBody.replaceAll("\r", "") : null;
+            this.textBody =
+                    textBody != null
+                            ? RegexPatternUtils.getInstance()
+                                    .getCarriageReturnPattern()
+                                    .matcher(textBody)
+                                    .replaceAll("")
+                            : null;
         }
     }
 

app/common/src/main/java/stirling/software/common/util/EmlProcessingUtils.java

@@ -199,8 +199,16 @@ public class EmlProcessingUtils {
         String processed =
                 customHtmlSanitizer != null ? customHtmlSanitizer.sanitize(htmlBody) : htmlBody;
 
-        processed = processed.replaceAll("(?i)\\s*position\\s*:\\s*fixed[^;]*;?", "");
+        processed =
-        processed = processed.replaceAll("(?i)\\s*position\\s*:\\s*absolute[^;]*;?", "");
+                RegexPatternUtils.getInstance()
+                        .getFixedPositionCssPattern()
+                        .matcher(processed)
+                        .replaceAll("");
+        processed =
+                RegexPatternUtils.getInstance()
+                        .getAbsolutePositionCssPattern()
+                        .matcher(processed)
+                        .replaceAll("");
 
         if (emailContent != null && !emailContent.getAttachments().isEmpty()) {
             processed = PdfAttachmentHandler.processInlineImages(processed, emailContent);
@@ -222,13 +230,17 @@ public class EmlProcessingUtils {
         html = html.replace("\n", "<br>\n");
 
         html =
-                html.replaceAll(
+                RegexPatternUtils.getInstance()
-                        "(https?://[\\w\\-._~:/?#\\[\\]@!$&'()*+,;=%]+)",
+                        .getUrlLinkPattern()
+                        .matcher(html)
+                        .replaceAll(
                                 "<a href=\"$1\" style=\"color: #1a73e8; text-decoration: underline;\">$1</a>");
 
         html =
-                html.replaceAll(
+                RegexPatternUtils.getInstance()
-                        "([a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\\.[a-zA-Z]{2,63})",
+                        .getEmailLinkPattern()
+                        .matcher(html)
+                        .replaceAll(
                                 "<a href=\"mailto:$1\" style=\"color: #1a73e8; text-decoration: underline;\">$1</a>");
 
         return html;
@@ -490,9 +502,13 @@ public class EmlProcessingUtils {
             Matcher concatenatedMatcher = concatenatedPattern.matcher(encodedText);
             String processedText =
                     concatenatedMatcher.replaceAll(
-                            match -> match.group().replaceAll("\\s+(?==\\?)", ""));
+                            match ->
+                                    RegexPatternUtils.getInstance()
+                                            .getMimeHeaderWhitespacePattern()
+                                            .matcher(match.group())
+                                            .replaceAll(""));
 
-            Pattern mimePattern = Pattern.compile("=\\?([^?]+)\\?([BbQq])\\?([^?]*)\\?=");
+            Pattern mimePattern = RegexPatternUtils.getInstance().getMimeEncodedWordPattern();
             Matcher matcher = mimePattern.matcher(processedText);
             int lastEnd = 0;
 
@@ -507,7 +523,11 @@ public class EmlProcessingUtils {
                     String decodedValue =
                             switch (encoding) {
                                 case "B" -> {
-                                    String cleanBase64 = encodedValue.replaceAll("\\s", "");
+                                    String cleanBase64 =
+                                            RegexPatternUtils.getInstance()
+                                                    .getWhitespacePattern()
+                                                    .matcher(encodedValue)
+                                                    .replaceAll("");
                                     byte[] decodedBytes = Base64.getDecoder().decode(cleanBase64);
                                     Charset targetCharset;
                                     try {
@@ -596,8 +616,16 @@ public class EmlProcessingUtils {
     }
 
     public static String simplifyHtmlContent(String htmlContent) {
-        String simplified = htmlContent.replaceAll("(?i)<script[^>]*>.*?</script>", "");
+        String simplified =
-        simplified = simplified.replaceAll("(?i)<style[^>]*>.*?</style>", "");
+                RegexPatternUtils.getInstance()
+                        .getScriptTagPattern()
+                        .matcher(htmlContent)
+                        .replaceAll("");
+        simplified =
+                RegexPatternUtils.getInstance()
+                        .getStyleTagPattern()
+                        .matcher(simplified)
+                        .replaceAll("");
         return simplified;
     }
 }

app/common/src/main/java/stirling/software/common/util/FileToPdf.java

@@ -1,6 +1,9 @@
 package stirling.software.common.util;
 
-import java.io.*;
+import java.io.ByteArrayInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.UncheckedIOException;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.FileVisitResult;
 import java.nio.file.Files;
@@ -205,15 +208,27 @@ public class FileToPdf {
             return "";
         }
         // Remove any drive letters (e.g., "C:\") and leading forward/backslashes
-        entryName = entryName.replaceAll("^[a-zA-Z]:[\\\\/]+", "");
+        entryName =
-        entryName = entryName.replaceAll("^[\\\\/]+", "");
+                RegexPatternUtils.getInstance()
+                        .getDriveLetterPattern()
+                        .matcher(entryName)
+                        .replaceAll("");
+        entryName =
+                RegexPatternUtils.getInstance()
+                        .getLeadingSlashesPattern()
+                        .matcher(entryName)
+                        .replaceAll("");
 
         // Recursively remove path traversal sequences
         while (entryName.contains("../") || entryName.contains("..\\")) {
             entryName = entryName.replace("../", "").replace("..\\", "");
         }
         // Normalize all backslashes to forward slashes
-        entryName = entryName.replaceAll("\\\\", "/");
+        entryName =
+                RegexPatternUtils.getInstance()
+                        .getBackslashPattern()
+                        .matcher(entryName)
+                        .replaceAll("/");
         return entryName;
     }
 }

app/common/src/main/java/stirling/software/common/util/GeneralUtils.java

@@ -9,13 +9,9 @@ import java.nio.charset.StandardCharsets;
 import java.nio.file.*;
 import java.nio.file.attribute.BasicFileAttributes;
 import java.security.MessageDigest;
-import java.util.ArrayList;
+import java.util.*;
-import java.util.Arrays;
+import java.util.regex.Matcher;
-import java.util.Enumeration;
+import java.util.regex.Pattern;
-import java.util.List;
-import java.util.Locale;
-import java.util.Set;
-import java.util.UUID;
 
 import org.springframework.core.io.ClassPathResource;
 import org.springframework.core.io.Resource;
@@ -28,25 +24,37 @@ import com.fathzer.soft.javaluator.DoubleEvaluator;
 import io.github.pixee.security.HostValidator;
 import io.github.pixee.security.Urls;
 
+import lombok.experimental.UtilityClass;
 import lombok.extern.slf4j.Slf4j;
 
 import stirling.software.common.configuration.InstallationPathConfig;
 
 @Slf4j
+@UtilityClass
 public class GeneralUtils {
 
-    private static final Set<String> DEFAULT_VALID_SCRIPTS =
+    private final Set<String> DEFAULT_VALID_SCRIPTS = Set.of("png_to_webp.py", "split_photos.py");
-            Set.of("png_to_webp.py", "split_photos.py");
+    private final Set<String> DEFAULT_VALID_PIPELINE =
-    private static final Set<String> DEFAULT_VALID_PIPELINE =
             Set.of(
                     "OCR images.json",
                     "Prepare-pdfs-for-email.json",
                     "split-rotate-auto-rename.json");
 
-    private static final String DEFAULT_WEBUI_CONFIGS_DIR = "defaultWebUIConfigs";
+    private final String DEFAULT_WEBUI_CONFIGS_DIR = "defaultWebUIConfigs";
-    private static final String PYTHON_SCRIPTS_DIR = "python";
+    private final String PYTHON_SCRIPTS_DIR = "python";
+    private final RegexPatternUtils patternCache = RegexPatternUtils.getInstance();
+    // Valid size units used for convertSizeToBytes validation and parsing
+    private final Set<String> VALID_SIZE_UNITS = Set.of("B", "KB", "MB", "GB", "TB");
 
-    public static File convertMultipartFileToFile(MultipartFile multipartFile) throws IOException {
+    /*
+     * Converts a MultipartFile to a regular File with improved performance and security.
+     *
+     * @param multipartFile the multipart file to convert
+     * @return temporary File containing the multipart file data
+     * @throws IOException if I/O error occurs during conversion
+     * @throws IllegalArgumentException if file exceeds maximum allowed size
+     */
+    public File convertMultipartFileToFile(MultipartFile multipartFile) throws IOException {
         String customTempDir = System.getenv("STIRLING_TEMPFILES_DIRECTORY");
         if (customTempDir == null || customTempDir.isEmpty()) {
             customTempDir = System.getProperty("stirling.tempfiles.directory");
@@ -81,10 +89,137 @@ public class GeneralUtils {
         return tempFile;
     }
 
-    public static void deleteDirectory(Path path) throws IOException {
+    /*
+     * Gets the configured temporary directory, creating it if necessary.
+     *
+     * @return Path to the temporary directory
+     * @throws IOException if directory creation fails
+     */
+    private Path getTempDirectory() throws IOException {
+        String customTempDir = System.getenv("STIRLING_TEMPFILES_DIRECTORY");
+        if (customTempDir == null || customTempDir.isEmpty()) {
+            customTempDir = System.getProperty("stirling.tempfiles.directory");
+        }
+
+        Path tempDir;
+        if (customTempDir != null && !customTempDir.isEmpty()) {
+            tempDir = Path.of(customTempDir);
+        } else {
+            tempDir = Path.of(System.getProperty("java.io.tmpdir"), "stirling-pdf");
+        }
+
+        if (!Files.exists(tempDir)) {
+            Files.createDirectories(tempDir);
+        }
+
+        return tempDir;
+    }
+
+    /*
+     * Remove file extension
+     *
+     * <p>Uses fast string operations for common cases (valid extensions) and falls back to
+     * optimized regex for edge cases (no extension, hidden files, etc.).
+     *
+     * <ul>
+     *   <li>String operations avoid regex engine overhead for common cases
+     *   <li>Cached pattern compilation eliminates recompilation costs
+     *   <li>Fresh Matcher instances ensure thread safety
+     * </ul>
+     *
+     * @param filename the filename to process, may be null
+     * @return filename without extension, or "default" if input is null
+     */
+    public String removeExtension(String filename) {
+        if (filename == null) {
+            return "default";
+        }
+
+        if (filename.isEmpty()) {
+            return filename;
+        }
+
+        int dotIndex = filename.lastIndexOf('.');
+        if (dotIndex > 0 && dotIndex < filename.length() - 1) {
+            return filename.substring(0, dotIndex);
+        }
+
+        if (dotIndex == 0 || dotIndex == filename.length() - 1 || dotIndex == -1) {
+            return filename;
+        }
+
+        Pattern pattern = patternCache.getPattern(RegexPatternUtils.getExtensionRegex());
+        Matcher matcher = pattern.matcher(filename);
+        return matcher.find() ? matcher.replaceFirst("") : filename;
+    }
+
+    /*
+     * Append suffix to base name with null safety.
+     *
+     * @param baseName the base filename, null becomes "default"
+     * @param suffix the suffix to append, null becomes empty string
+     * @return concatenated string with null safety
+     */
+    public String appendSuffix(String baseName, String suffix) {
+        return (baseName == null ? "default" : baseName) + (suffix != null ? suffix : "");
+    }
+
+    /*
+     * Generate a PDF filename by removing extension from first file and adding suffix.
+     *
+     * <p>High-level utility method for common PDF naming scenarios. Handles null safety and uses
+     * extension removal.
+     *
+     * @param firstFilename the filename of the first file being, may be null
+     * @param suffix the suffix to append (e.g., "_merged.pdf")
+     * @return filename with suffix, or default name if input is null
+     */
+    public String generateFilename(String firstFilename, String suffix) {
+        String baseName = removeExtension(firstFilename);
+        return appendSuffix(baseName, suffix);
+    }
+
+    /*
+     * Process a list of filenames by removing extensions and adding suffix.
+     *
+     * <p>Efficiently processes multiple filenames using streaming operations and bulk operations
+     * where possible. Handles null safety for both input list and individual filenames.
+     *
+     * @param filenames the list of filenames to process, may be null
+     * @param suffix the suffix to append to each processed filename
+     * @param processor consumer to handle each processed filename, may be null
+     */
+    public void processFilenames(
+            List<String> filenames, String suffix, java.util.function.Consumer<String> processor) {
+        if (filenames == null || processor == null) {
+            return;
+        }
+
+        filenames.stream()
+                .map(filename -> appendSuffix(removeExtension(filename), suffix))
+                .forEach(processor);
+    }
+
+    /*
+     * Extract title from filename by removing extension, with fallback handling.
+     *
+     * <p>Returns "Untitled" for null or empty filenames, otherwise removes the extension using the
+     * optimized removeExtension method.
+     *
+     * @param filename the filename to extract title from, may be null
+     * @return the title without extension, or "Untitled" if input is null/empty
+     */
+    public String getTitleFromFilename(String filename) {
+        if (filename == null || filename.isEmpty()) {
+            return "Untitled";
+        }
+        return removeExtension(filename);
+    }
+
+    public void deleteDirectory(Path path) throws IOException {
         Files.walkFileTree(
                 path,
-                new SimpleFileVisitor<Path>() {
+                new SimpleFileVisitor<>() {
                     @Override
                     public FileVisitResult visitFile(Path file, BasicFileAttributes attrs)
                             throws IOException {
@@ -101,8 +236,18 @@ public class GeneralUtils {
                 });
     }
 
-    public static String convertToFileName(String name) {
+    public String convertToFileName(String name) {
-        String safeName = name.replaceAll("[^a-zA-Z0-9]", "_");
+        if (name == null) return "_";
+        StringBuilder safeNameBuilder = new StringBuilder(name.length());
+        for (int i = 0; i < name.length(); i++) {
+            char c = name.charAt(i);
+            if (Character.isLetterOrDigit(c)) {
+                safeNameBuilder.append(c);
+            } else {
+                safeNameBuilder.append('_');
+            }
+        }
+        String safeName = safeNameBuilder.toString();
         if (safeName.length() > 50) {
             safeName = safeName.substring(0, 50);
         }
@@ -110,19 +255,20 @@ public class GeneralUtils {
     }
 
     // Get resources from a location pattern
-    public static Resource[] getResourcesFromLocationPattern(
+    public Resource[] getResourcesFromLocationPattern(
             String locationPattern, ResourceLoader resourceLoader) throws Exception {
         // Normalize the path for file resources
-        if (locationPattern.startsWith("file:")) {
+        String pattern = locationPattern;
-            String rawPath = locationPattern.substring(5).replace("\\*", "").replace("/*", "");
+        if (pattern.startsWith("file:")) {
+            String rawPath = pattern.substring(5).replace("\\*", "").replace("/*", "");
             Path normalizePath = Paths.get(rawPath).normalize();
-            locationPattern = "file:" + normalizePath.toString().replace("\\", "/") + "/*";
+            pattern = "file:" + normalizePath.toString().replace("\\", "/") + "/*";
         }
         return ResourcePatternUtils.getResourcePatternResolver(resourceLoader)
-                .getResources(locationPattern);
+                .getResources(pattern);
     }
 
-    public static boolean isValidURL(String urlStr) {
+    public boolean isValidURL(String urlStr) {
         try {
             Urls.create(
                     urlStr, Urls.HTTP_PROTOCOLS, HostValidator.DENY_COMMON_INFRASTRUCTURE_TARGETS);
@@ -132,7 +278,25 @@ public class GeneralUtils {
         }
     }
 
-    public static boolean isURLReachable(String urlStr) {
+    /*
+     * Checks if a URL is reachable with proper timeout configuration and error handling.
+     *
+     * @param urlStr the URL string to check
+     * @return true if URL is reachable, false otherwise
+     */
+    public boolean isURLReachable(String urlStr) {
+        return isURLReachable(urlStr, 5000, 5000);
+    }
+
+    /*
+     * Checks if a URL is reachable with configurable timeouts.
+     *
+     * @param urlStr the URL string to check
+     * @param connectTimeout connection timeout in milliseconds
+     * @param readTimeout read timeout in milliseconds
+     * @return true if URL is reachable, false otherwise
+     */
+    public boolean isURLReachable(String urlStr, int connectTimeout, int readTimeout) {
         try {
             // Parse the URL
             URL url = URI.create(urlStr).toURL();
@@ -152,16 +316,19 @@ public class GeneralUtils {
             // Check if the URL is reachable
             HttpURLConnection connection = (HttpURLConnection) url.openConnection();
             connection.setRequestMethod("HEAD");
-            // connection.setConnectTimeout(5000); // Set connection timeout
+            connection.setConnectTimeout(connectTimeout);
-            // connection.setReadTimeout(5000);    // Set read timeout
+            connection.setReadTimeout(readTimeout);
+            connection.setInstanceFollowRedirects(false); // Security: prevent redirect loops
+
             int responseCode = connection.getResponseCode();
             return (200 <= responseCode && responseCode <= 399);
         } catch (Exception e) {
+            log.debug("URL {} is not reachable: {}", urlStr, e.getMessage());
             return false; // Return false in case of any exception
         }
     }
 
-    private static boolean isLocalAddress(String host) {
+    private boolean isLocalAddress(String host) {
         try {
             // Resolve DNS to IP address
             InetAddress address = InetAddress.getByName(host);
@@ -181,7 +348,14 @@ public class GeneralUtils {
         }
     }
 
-    public static File multipartToFile(MultipartFile multipart) throws IOException {
+    /*
+     * Improved multipart file conversion using the shared helper method.
+     *
+     * @param multipart the multipart file to convert
+     * @return temporary File containing the multipart file data
+     * @throws IOException if I/O error occurs during conversion
+     */
+    public File multipartToFile(MultipartFile multipart) throws IOException {
         Path tempFile = Files.createTempFile("overlay-", ".pdf");
         try (InputStream in = multipart.getInputStream();
                 FileOutputStream out = new FileOutputStream(tempFile.toFile())) {
@@ -194,54 +368,105 @@ public class GeneralUtils {
         return tempFile.toFile();
     }
 
-    public static Long convertSizeToBytes(String sizeStr) {
+    /*
+     * Supports TB/PB units and provides detailed error messages.
+     *
+     * @param sizeStr the size string to convert (e.g., "100MB", "1.5GB")
+     * @param defaultUnit the default unit to assume if none specified ("MB", "GB", etc.)
+     * @return size in bytes, or null if parsing fails
+     * @throws IllegalArgumentException if defaultUnit is invalid
+     */
+    public Long convertSizeToBytes(String sizeStr, String defaultUnit) {
         if (sizeStr == null) {
             return null;
         }
 
+        if (defaultUnit != null && !isValidSizeUnit(defaultUnit)) {
+            throw new IllegalArgumentException("Invalid default unit: " + defaultUnit);
+        }
+
         sizeStr = sizeStr.trim().toUpperCase();
         sizeStr = sizeStr.replace(",", ".").replace(" ", "");
+
         try {
-            if (sizeStr.endsWith("KB")) {
+            if (sizeStr.endsWith("TB")) {
-                return (long)
-                        (Double.parseDouble(sizeStr.substring(0, sizeStr.length() - 2)) * 1024);
-            } else if (sizeStr.endsWith("MB")) {
                 return (long)
                         (Double.parseDouble(sizeStr.substring(0, sizeStr.length() - 2))
-                                * 1024
+                                * 1024L
-                                * 1024);
+                                * 1024L
+                                * 1024L
+                                * 1024L);
             } else if (sizeStr.endsWith("GB")) {
                 return (long)
                         (Double.parseDouble(sizeStr.substring(0, sizeStr.length() - 2))
-                                * 1024
+                                * 1024L
-                                * 1024
+                                * 1024L
-                                * 1024);
+                                * 1024L);
-            } else if (sizeStr.endsWith("B")) {
+            } else if (sizeStr.endsWith("MB")) {
+                return (long)
+                        (Double.parseDouble(sizeStr.substring(0, sizeStr.length() - 2))
+                                * 1024L
+                                * 1024L);
+            } else if (sizeStr.endsWith("KB")) {
+                return (long)
+                        (Double.parseDouble(sizeStr.substring(0, sizeStr.length() - 2)) * 1024L);
+            } else if (!sizeStr.isEmpty() && sizeStr.charAt(sizeStr.length() - 1) == 'B') {
                 return Long.parseLong(sizeStr.substring(0, sizeStr.length() - 1));
             } else {
-                // Assume MB if no unit is specified
+                // Use provided default unit or fall back to MB
-                return (long) (Double.parseDouble(sizeStr) * 1024 * 1024);
+                String unit = defaultUnit != null ? defaultUnit.toUpperCase() : "MB";
+                double value = Double.parseDouble(sizeStr);
+                return switch (unit) {
+                    case "TB" -> (long) (value * 1024L * 1024L * 1024L * 1024L);
+                    case "GB" -> (long) (value * 1024L * 1024L * 1024L);
+                    case "MB" -> (long) (value * 1024L * 1024L);
+                    case "KB" -> (long) (value * 1024L);
+                    case "B" -> (long) value;
+                    default -> (long) (value * 1024L * 1024L); // Default to MB
+                };
             }
         } catch (NumberFormatException e) {
-            // The numeric part of the input string cannot be parsed, handle this case
+            log.warn("Failed to parse size string '{}': {}", sizeStr, e.getMessage());
-        }
-
             return null;
         }
+    }
+
+    /*
+     * Converts size string to bytes using MB as default unit.
+     *
+     * @param sizeStr the size string to convert
+     * @return size in bytes, or null if parsing fails
+     */
+    public Long convertSizeToBytes(String sizeStr) {
+        return convertSizeToBytes(sizeStr, "MB");
+    }
+
+    /* Validates if a string represents a valid size unit. */
+    private boolean isValidSizeUnit(String unit) {
+        // Use a precomputed Set for O(1) lookup, normalize using a locale-safe toUpperCase
+        return unit != null && VALID_SIZE_UNITS.contains(unit.toUpperCase(Locale.ROOT));
+    }
+
+    /* Enhanced byte formatting with TB/PB support and better precision. */
+    public String formatBytes(long bytes) {
+        if (bytes < 0) {
+            return "Invalid size";
+        }
 
-    public static String formatBytes(long bytes) {
         if (bytes < 1024) {
             return bytes + " B";
-        } else if (bytes < 1024 * 1024) {
+        } else if (bytes < 1024L * 1024L) {
             return String.format(Locale.US, "%.2f KB", bytes / 1024.0);
-        } else if (bytes < 1024 * 1024 * 1024) {
+        } else if (bytes < 1024L * 1024L * 1024L) {
             return String.format(Locale.US, "%.2f MB", bytes / (1024.0 * 1024.0));
-        } else {
+        } else if (bytes < 1024L * 1024L * 1024L * 1024L) {
             return String.format(Locale.US, "%.2f GB", bytes / (1024.0 * 1024.0 * 1024.0));
+        } else {
+            return String.format(Locale.US, "%.2f TB", bytes / (1024.0 * 1024.0 * 1024.0 * 1024.0));
         }
     }
 
-    public static List<Integer> parsePageList(String pages, int totalPages, boolean oneBased) {
+    public List<Integer> parsePageList(String pages, int totalPages, boolean oneBased) {
         if (pages == null) {
             return List.of(1); // Default to first page if input is null
         }
@@ -252,11 +477,11 @@ public class GeneralUtils {
         }
     }
 
-    public static List<Integer> parsePageList(String[] pages, int totalPages) {
+    public List<Integer> parsePageList(String[] pages, int totalPages) {
         return parsePageList(pages, totalPages, false);
     }
 
-    public static List<Integer> parsePageList(String[] pages, int totalPages, boolean oneBased) {
+    public List<Integer> parsePageList(String[] pages, int totalPages, boolean oneBased) {
         List<Integer> result = new ArrayList<>();
         int offset = oneBased ? 1 : 0;
         for (String page : pages) {
@@ -278,33 +503,72 @@ public class GeneralUtils {
         return result;
     }
 
-    public static List<Integer> evaluateNFunc(String expression, int maxValue) {
+    /*
+     * Enhanced mathematical expression evaluation with bounds checking and timeout protection.
+     *
+     * @param expression the mathematical expression containing 'n'
+     * @param maxValue the maximum value for 'n' and result bounds
+     * @return list of valid page numbers
+     * @throws IllegalArgumentException if expression is invalid or unsafe
+     */
+    public List<Integer> evaluateNFunc(String expression, int maxValue) {
+        if (expression == null || expression.trim().isEmpty()) {
+            throw new IllegalArgumentException("Expression cannot be null or empty");
+        }
+
+        if (maxValue <= 0 || maxValue > 10000) {
+            throw new IllegalArgumentException("maxValue must be between 1 and 10000 for safety");
+        }
+
         List<Integer> results = new ArrayList<>();
         DoubleEvaluator evaluator = new DoubleEvaluator();
 
-        // Validate the expression
+        // Validate the expression format
-        if (!expression.matches("[0-9n+\\-*/() ]+")) {
+        if (!RegexPatternUtils.getInstance()
-            throw new IllegalArgumentException("Invalid expression");
+                .getMathExpressionPattern()
+                .matcher(expression.trim())
+                .matches()) {
+            throw new IllegalArgumentException("Invalid expression format: " + expression);
         }
 
         for (int n = 1; n <= maxValue; n++) {
-            // Replace 'n' with the current value of n, correctly handling numbers before
+            try {
-            // 'n'
+                // Replace 'n' with the current value of n, correctly handling numbers before 'n'
-            String sanitizedExpression = sanitizeNFunction(expression, n);
+                String sanitizedExpression = sanitizeNFunction(expression.trim(), n);
                 Double result = evaluator.evaluate(sanitizedExpression);
 
                 // Check if the result is null or not within bounds
-            if (result == null) break;
+                if (result == null || !Double.isFinite(result)) {
+                    continue;
+                }
 
-            if (result.intValue() > 0 && result.intValue() <= maxValue)
+                int intResult = result.intValue();
-                results.add(result.intValue());
+                if (intResult > 0 && intResult <= maxValue) {
+                    results.add(intResult);
+                }
+            } catch (Exception e) {
+                log.debug(
+                        "Failed to evaluate expression '{}' for n={}: {}",
+                        expression,
+                        n,
+                        e.getMessage());
+                // Continue with next value instead of breaking
+            }
         }
 
         return results;
     }
 
-    private static String sanitizeNFunction(String expression, int nValue) {
+    private String sanitizeNFunction(String expression, int nValue) {
-        String sanitizedExpression = expression.replace(" ", "");
+        // Remove all spaces using a specialized character removal
+        StringBuilder sb = new StringBuilder(expression.length());
+        for (int i = 0; i < expression.length(); i++) {
+            char c = expression.charAt(i);
+            if (c != ' ') {
+                sb.append(c);
+            }
+        }
+        String sanitizedExpression = sb.toString();
         String multiplyByOpeningRoundBracketPattern =
                 "([0-9n)])\\("; // example: n(n-1), 9(n-1), (n-1)(n-2)
         sanitizedExpression =
@@ -319,23 +583,45 @@ public class GeneralUtils {
         return sanitizedExpression;
     }
 
-    private static String insertMultiplicationBeforeN(String expression, int nValue) {
+    private String insertMultiplicationBeforeN(String expression, int nValue) {
-        // Insert multiplication between a number and 'n' (e.g., "4n" becomes "4*n")
+        // Insert multiplication between a number and 'n' (e.g., "4n" becomes "4*n") using a loop
-        String withMultiplication = expression.replaceAll("(\\d)n", "$1*n");
+        StringBuilder sb = new StringBuilder(expression.length() + 4); // +4 for possible extra '*'
+        for (int i = 0; i < expression.length(); i++) {
+            char c = expression.charAt(i);
+            sb.append(c);
+            if (Character.isDigit(c)
+                    && i + 1 < expression.length()
+                    && expression.charAt(i + 1) == 'n') {
+                sb.append('*');
+            }
+        }
+        String withMultiplication = sb.toString();
         withMultiplication = formatConsecutiveNsForNFunction(withMultiplication);
         // Now replace 'n' with its current value
         return withMultiplication.replace("n", String.valueOf(nValue));
     }
 
-    private static String formatConsecutiveNsForNFunction(String expression) {
+    private String formatConsecutiveNsForNFunction(String expression) {
         String text = expression;
-        while (text.matches(".*n{2,}.*")) {
+        // Replace all consecutive 'nn' with 'n*n' until no more 'nn' is found
-            text = text.replaceAll("(?<!n)n{2}", "n*n");
+        while (text.contains("nn")) {
+            StringBuilder sb = new StringBuilder(text.length() + 2); // +2 for possible extra '*'
+            int i = 0;
+            while (i < text.length()) {
+                if (i < text.length() - 1 && text.charAt(i) == 'n' && text.charAt(i + 1) == 'n') {
+                    sb.append("n*n");
+                    i += 2;
+                } else {
+                    sb.append(text.charAt(i));
+                    i++;
+                }
+            }
+            text = sb.toString();
         }
         return text;
     }
 
-    private static List<Integer> handlePart(String part, int totalPages, int offset) {
+    private List<Integer> handlePart(String part, int totalPages, int offset) {
         List<Integer> partResult = new ArrayList<>();
 
         // First check for n-syntax because it should not be processed as a range
@@ -361,7 +647,7 @@ public class GeneralUtils {
                     }
                 }
             } catch (NumberFormatException e) {
-                // Range is invalid, ignore this part
+                log.debug("Invalid range: {}", part);
             }
         } else {
             // This is a single page number
@@ -370,14 +656,14 @@ public class GeneralUtils {
                 if (pageNum >= 1 && pageNum <= totalPages) {
                     partResult.add(pageNum - 1 + offset);
                 }
-            } catch (NumberFormatException ignored) {
+            } catch (NumberFormatException e) {
-                // Ignore invalid numbers
+                log.debug("Invalid page number: {}", part);
             }
         }
         return partResult;
     }
 
-    public static boolean createDir(String path) {
+    public boolean createDir(String path) {
         Path folder = Paths.get(path);
         if (!Files.exists(folder)) {
             try {
@@ -390,7 +676,7 @@ public class GeneralUtils {
         return true;
     }
 
-    public static boolean isValidUUID(String uuid) {
+    public boolean isValidUUID(String uuid) {
         if (uuid == null) {
             return false;
         }
@@ -406,7 +692,7 @@ public class GeneralUtils {
      *                  Internal Implementation Details                       *
      *------------------------------------------------------------------------*/
 
-    public static void saveKeyToSettings(String key, Object newValue) throws IOException {
+    public void saveKeyToSettings(String key, Object newValue) throws IOException {
         String[] keyArray = key.split("\\.");
         Path settingsPath = Paths.get(InstallationPathConfig.getSettingsPath());
         YamlHelper settingsYaml = new YamlHelper(settingsPath);
@@ -414,48 +700,67 @@ public class GeneralUtils {
         settingsYaml.saveOverride(settingsPath);
     }
 
-    public static String generateMachineFingerprint() {
+    /*
+     * Machine fingerprint generation with better error logging and fallbacks.
+     *
+     * @return unique machine fingerprint or "GenericID" if generation fails
+     */
+    public String generateMachineFingerprint() {
         try {
-            // Get the MAC address
             StringBuilder sb = new StringBuilder();
+
+            // Try to get MAC address from primary network interface
             InetAddress ip = InetAddress.getLocalHost();
             NetworkInterface network = NetworkInterface.getByInetAddress(ip);
 
-            if (network == null) {
+            if (network == null || network.getHardwareAddress() == null) {
+                // Fallback: iterate through all network interfaces
                 Enumeration<NetworkInterface> networks = NetworkInterface.getNetworkInterfaces();
                 while (networks.hasMoreElements()) {
                     NetworkInterface net = networks.nextElement();
+                    if (net.isUp() && !net.isLoopback() && !net.isVirtual()) {
                         byte[] mac = net.getHardwareAddress();
-                    if (mac != null) {
+                        if (mac != null && mac.length > 0) {
-                        for (int i = 0; i < mac.length; i++) {
+                            for (byte b : mac) {
-                            sb.append(String.format("%02X", mac[i]));
+                                sb.append(String.format("%02X", b));
+                            }
+                            break; // Use the first valid network interface
                         }
-                        break; // Use the first network interface with a MAC address
                     }
                 }
             } else {
                 byte[] mac = network.getHardwareAddress();
                 if (mac != null) {
-                    for (int i = 0; i < mac.length; i++) {
+                    for (byte b : mac) {
-                        sb.append(String.format("%02X", mac[i]));
+                        sb.append(String.format("%02X", b));
                     }
                 }
             }
 
-            // Hash the MAC address for privacy and consistency
+            // If no MAC address found, use hostname as fallback
+            if (sb.length() == 0) {
+                String hostname = InetAddress.getLocalHost().getHostName();
+                sb.append(hostname != null ? hostname : "unknown-host");
+                log.warn("No MAC address found, using hostname for fingerprint generation");
+            }
+
+            // Hash the collected data for privacy and consistency
             MessageDigest md = MessageDigest.getInstance("SHA-256");
             byte[] hash = md.digest(sb.toString().getBytes(StandardCharsets.UTF_8));
             StringBuilder fingerprint = new StringBuilder();
             for (byte b : hash) {
                 fingerprint.append(String.format("%02x", b));
             }
+
+            log.debug("Successfully generated machine fingerprint");
             return fingerprint.toString();
         } catch (Exception e) {
+            log.warn("Failed to generate machine fingerprint: {}", e.getMessage());
             return "GenericID";
         }
     }
 
-    /**
+    /*
      * Extracts the default pipeline configurations from the classpath to the installation path.
      * Creates directories if needed and copies default JSON files.
      *
@@ -464,7 +769,7 @@ public class GeneralUtils {
      *
      * @throws IOException if an I/O error occurs during file operations
      */
-    public static void extractPipeline() throws IOException {
+    public void extractPipeline() throws IOException {
         Path pipelineDir =
                 Paths.get(InstallationPathConfig.getPipelinePath(), DEFAULT_WEBUI_CONFIGS_DIR);
         Files.createDirectories(pipelineDir);
@@ -486,7 +791,7 @@ public class GeneralUtils {
         }
     }
 
-    /**
+    /*
      * Extracts the specified Python script from the classpath to the installation path. Validates
      * name and copies file atomically when possible, overwriting existing.
      *
@@ -497,7 +802,7 @@ public class GeneralUtils {
      * @throws IllegalArgumentException if the script name is invalid or not allowed
      * @throws IOException if an I/O error occurs
      */
-    public static Path extractScript(String scriptName) throws IOException {
+    public Path extractScript(String scriptName) throws IOException {
         // Validate input
         if (scriptName == null || scriptName.trim().isEmpty()) {
             throw new IllegalArgumentException("scriptName must not be null or empty");
@@ -530,15 +835,14 @@ public class GeneralUtils {
         return target;
     }
 
-    /**
+    /*
      * Copies a resource from the classpath to a specified target file.
      *
      * @param resource the ClassPathResource to copy
      * @param target the target Path where the resource will be copied
      * @throws IOException if an I/O error occurs during the copy operation
      */
-    private static void copyResourceToFile(ClassPathResource resource, Path target)
+    private void copyResourceToFile(ClassPathResource resource, Path target) throws IOException {
-            throws IOException {
         Path dir = target.getParent();
         Path tmp = Files.createTempFile(dir, target.getFileName().toString(), ".tmp");
         try (InputStream in = resource.getInputStream()) {
@@ -573,7 +877,7 @@ public class GeneralUtils {
         }
     }
 
-    public static boolean isVersionHigher(String currentVersion, String compareVersion) {
+    public boolean isVersionHigher(String currentVersion, String compareVersion) {
         if (currentVersion == null || compareVersion == null) {
             return false;
         }

app/common/src/main/java/stirling/software/common/util/PdfAttachmentHandler.java

@@ -258,10 +258,7 @@ public class PdfAttachmentHandler {
 
         if (contentIdMap.isEmpty()) return htmlContent;
 
-        Pattern cidPattern =
+        Pattern cidPattern = RegexPatternUtils.getInstance().getInlineCidImagePattern();
-                Pattern.compile(
-                        "(?i)<img[^>]*\\ssrc\\s*=\\s*['\"]cid:([^'\"]+)['\"][^>]*>",
-                        Pattern.CASE_INSENSITIVE);
         Matcher matcher = cidPattern.matcher(htmlContent);
 
         StringBuilder result = new StringBuilder();
@@ -319,121 +316,20 @@ public class PdfAttachmentHandler {
         }
     }
 
-    public static class AttachmentMarkerPositionFinder extends PDFTextStripper {
+    private static String normalizeFilename(String filename) {
-        @Getter private final List<MarkerPosition> positions = new ArrayList<>();
+        if (filename == null) return "";
-        private int currentPageIndex;
+        String normalized = filename.toLowerCase().trim();
-        protected boolean sortByPosition;
+        normalized =
-        private boolean isInAttachmentSection;
+                RegexPatternUtils.getInstance()
-        private boolean attachmentSectionFound;
+                        .getWhitespacePattern()
-        private final StringBuilder currentText = new StringBuilder();
+                        .matcher(normalized)
-
+                        .replaceAll(" ");
-        private static final Pattern ATTACHMENT_SECTION_PATTERN =
+        normalized =
-                Pattern.compile("attachments\\s*\\(\\d+\\)", Pattern.CASE_INSENSITIVE);
+                RegexPatternUtils.getInstance()
-
+                        .getPattern("[^a-zA-Z0-9._-]")
-        private static final Pattern FILENAME_PATTERN =
+                        .matcher(normalized)
-                Pattern.compile("@\\s*([^\\s\\(]+(?:\\.[a-zA-Z0-9]+)?)");
+                        .replaceAll("");
-
+        return normalized;
-        public AttachmentMarkerPositionFinder() {
-            super();
-            this.currentPageIndex = 0;
-            this.sortByPosition = false; // Disable sorting to preserve document order
-            this.isInAttachmentSection = false;
-            this.attachmentSectionFound = false;
-        }
-
-        @Override
-        public String getText(PDDocument document) throws IOException {
-            super.getText(document);
-
-            if (sortByPosition) {
-                positions.sort(
-                        (a, b) -> {
-                            int pageCompare = Integer.compare(a.getPageIndex(), b.getPageIndex());
-                            if (pageCompare != 0) return pageCompare;
-                            return Float.compare(
-                                    b.getY(), a.getY()); // Descending Y per PDF coordinate system
-                        });
-            }
-
-            return ""; // Return empty string as we only need positions
-        }
-
-        @Override
-        protected void startPage(PDPage page) throws IOException {
-            super.startPage(page);
-        }
-
-        @Override
-        protected void endPage(PDPage page) throws IOException {
-            currentPageIndex++;
-            super.endPage(page);
-        }
-
-        @Override
-        protected void writeString(String string, List<TextPosition> textPositions)
-                throws IOException {
-            String lowerString = string.toLowerCase();
-
-            if (ATTACHMENT_SECTION_PATTERN.matcher(lowerString).find()) {
-                isInAttachmentSection = true;
-                attachmentSectionFound = true;
-            }
-
-            if (isInAttachmentSection
-                    && (lowerString.contains("</body>")
-                            || lowerString.contains("</html>")
-                            || (attachmentSectionFound
-                                    && lowerString.trim().isEmpty()
-                                    && string.length() > 50))) {
-                isInAttachmentSection = false;
-            }
-
-            if (isInAttachmentSection) {
-                currentText.append(string);
-
-                for (int i = 0; (i = string.indexOf(ATTACHMENT_MARKER, i)) != -1; i++) {
-                    if (i < textPositions.size()) {
-                        TextPosition textPosition = textPositions.get(i);
-
-                        String filename = extractFilenameAfterMarker(string, i);
-
-                        MarkerPosition position =
-                                new MarkerPosition(
-                                        currentPageIndex,
-                                        textPosition.getXDirAdj(),
-                                        textPosition.getYDirAdj(),
-                                        ATTACHMENT_MARKER,
-                                        filename);
-                        positions.add(position);
-                    }
-                }
-            }
-            super.writeString(string, textPositions);
-        }
-
-        @Override
-        public void setSortByPosition(boolean sortByPosition) {
-            this.sortByPosition = sortByPosition;
-        }
-
-        private String extractFilenameAfterMarker(String text, int markerIndex) {
-            String afterMarker = text.substring(markerIndex + 1);
-
-            Matcher matcher = FILENAME_PATTERN.matcher("@" + afterMarker);
-            if (matcher.find()) {
-                return matcher.group(1);
-            }
-
-            String[] parts = afterMarker.split("[\\s\\(\\)]+");
-            for (String part : parts) {
-                part = part.trim();
-                if (part.length() > 3 && part.contains(".")) {
-                    return part;
-                }
-            }
-
-            return null;
-        }
     }
 
     private static Map<Integer, String> addAttachmentsToDocumentWithMapping(
@@ -613,12 +509,122 @@ public class PdfAttachmentHandler {
         return null;
     }
 
-    private static String normalizeFilename(String filename) {
+    public static class AttachmentMarkerPositionFinder extends PDFTextStripper {
-        if (filename == null) return "";
+        private static final Pattern ATTACHMENT_SECTION_PATTERN =
-        return filename.toLowerCase()
+                RegexPatternUtils.getInstance().getAttachmentSectionPattern();
-                .trim()
+        private static final Pattern FILENAME_PATTERN =
-                .replaceAll("\\s+", " ")
+                RegexPatternUtils.getInstance().getAttachmentFilenamePattern();
-                .replaceAll("[^a-zA-Z0-9._-]", "");
+        @Getter private final List<MarkerPosition> positions = new ArrayList<>();
+        private final StringBuilder currentText = new StringBuilder();
+        protected boolean sortByPosition;
+        private int currentPageIndex;
+        private boolean isInAttachmentSection;
+        private boolean attachmentSectionFound;
+
+        public AttachmentMarkerPositionFinder() {
+            super();
+            this.currentPageIndex = 0;
+            this.sortByPosition = false; // Disable sorting to preserve document order
+            this.isInAttachmentSection = false;
+            this.attachmentSectionFound = false;
+        }
+
+        @Override
+        public String getText(PDDocument document) throws IOException {
+            super.getText(document);
+
+            if (sortByPosition) {
+                positions.sort(
+                        (a, b) -> {
+                            int pageCompare = Integer.compare(a.getPageIndex(), b.getPageIndex());
+                            if (pageCompare != 0) return pageCompare;
+                            return Float.compare(
+                                    b.getY(), a.getY()); // Descending Y per PDF coordinate system
+                        });
+            }
+
+            return ""; // Return empty string as we only need positions
+        }
+
+        @Override
+        protected void startPage(PDPage page) throws IOException {
+            super.startPage(page);
+        }
+
+        @Override
+        protected void endPage(PDPage page) throws IOException {
+            currentPageIndex++;
+            super.endPage(page);
+        }
+
+        @Override
+        protected void writeString(String string, List<TextPosition> textPositions)
+                throws IOException {
+            String lowerString = string.toLowerCase();
+
+            if (ATTACHMENT_SECTION_PATTERN.matcher(lowerString).find()) {
+                isInAttachmentSection = true;
+                attachmentSectionFound = true;
+            }
+
+            if (isInAttachmentSection
+                    && (lowerString.contains("</body>")
+                            || lowerString.contains("</html>")
+                            || (attachmentSectionFound
+                                    && lowerString.trim().isEmpty()
+                                    && string.length() > 50))) {
+                isInAttachmentSection = false;
+            }
+
+            if (isInAttachmentSection) {
+                currentText.append(string);
+
+                for (int i = 0; (i = string.indexOf(ATTACHMENT_MARKER, i)) != -1; i++) {
+                    if (i < textPositions.size()) {
+                        TextPosition textPosition = textPositions.get(i);
+
+                        String filename = extractFilenameAfterMarker(string, i);
+
+                        MarkerPosition position =
+                                new MarkerPosition(
+                                        currentPageIndex,
+                                        textPosition.getXDirAdj(),
+                                        textPosition.getYDirAdj(),
+                                        ATTACHMENT_MARKER,
+                                        filename);
+                        positions.add(position);
+                    }
+                }
+            }
+            super.writeString(string, textPositions);
+        }
+
+        @Override
+        public void setSortByPosition(boolean sortByPosition) {
+            this.sortByPosition = sortByPosition;
+        }
+
+        private String extractFilenameAfterMarker(String text, int markerIndex) {
+            String afterMarker = text.substring(markerIndex + 1);
+
+            Matcher matcher = FILENAME_PATTERN.matcher("@" + afterMarker);
+            if (matcher.find()) {
+                return matcher.group(1);
+            }
+
+            String[] parts =
+                    RegexPatternUtils.getInstance()
+                            .getWhitespaceParenthesesSplitPattern()
+                            .split(afterMarker);
+            for (String part : parts) {
+                part = part.trim();
+                if (part.length() > 3 && part.contains(".")) {
+                    return part;
+                }
+            }
+
+            return null;
+        }
     }
 
     private static void addAttachmentAnnotationToPageWithMapping(

app/common/src/main/java/stirling/software/common/util/PdfUtils.java

@@ -8,6 +8,8 @@ import java.io.IOException;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
 import java.util.zip.ZipEntry;
 import java.util.zip.ZipOutputStream;
 
@@ -34,15 +36,20 @@ import org.springframework.web.multipart.MultipartFile;
 
 import io.github.pixee.security.Filenames;
 
+import lombok.experimental.UtilityClass;
 import lombok.extern.slf4j.Slf4j;
 
 import stirling.software.common.model.ApplicationProperties;
 import stirling.software.common.service.CustomPDFDocumentFactory;
 
 @Slf4j
+@UtilityClass
 public class PdfUtils {
 
-    public static PDRectangle textToPageSize(String size) {
+    private final RegexPatternUtils patternCache = RegexPatternUtils.getInstance();
+
+    public PDRectangle textToPageSize(String size) {
+
         switch (size.toUpperCase()) {
             case "A0" -> {
                 return PDRectangle.A0;
@@ -75,7 +82,7 @@ public class PdfUtils {
         }
     }
 
-    public static List<RenderedImage> getAllImages(PDResources resources) throws IOException {
+    public List<RenderedImage> getAllImages(PDResources resources) throws IOException {
         List<RenderedImage> images = new ArrayList<>();
 
         for (COSName name : resources.getXObjectNames()) {
@@ -92,7 +99,7 @@ public class PdfUtils {
         return images;
     }
 
-    public static boolean hasImages(PDDocument document, String pagesToCheck) throws IOException {
+    public boolean hasImages(PDDocument document, String pagesToCheck) throws IOException {
         String[] pageOrderArr = pagesToCheck.split(",");
         List<Integer> pageList =
                 GeneralUtils.parsePageList(pageOrderArr, document.getNumberOfPages());
@@ -107,7 +114,7 @@ public class PdfUtils {
         return false;
     }
 
-    public static boolean hasText(PDDocument document, String pageNumbersToCheck, String phrase)
+    public boolean hasText(PDDocument document, String pageNumbersToCheck, String phrase)
             throws IOException {
         String[] pageOrderArr = pageNumbersToCheck.split(",");
         List<Integer> pageList =
@@ -123,11 +130,11 @@ public class PdfUtils {
         return false;
     }
 
-    public static boolean hasImagesOnPage(PDPage page) throws IOException {
+    public boolean hasImagesOnPage(PDPage page) throws IOException {
         return getAllImages(page.getResources()).size() > 0;
     }
 
-    public static boolean hasTextOnPage(PDPage page, String phrase) throws IOException {
+    public boolean hasTextOnPage(PDPage page, String phrase) throws IOException {
         PDFTextStripper textStripper = new PDFTextStripper();
         PDDocument tempDoc = new PDDocument();
         tempDoc.addPage(page);
@@ -136,7 +143,7 @@ public class PdfUtils {
         return pageText.contains(phrase);
     }
 
-    public static byte[] convertFromPdf(
+    public byte[] convertFromPdf(
             CustomPDFDocumentFactory pdfDocumentFactory,
             byte[] inputStream,
             String imageType,
@@ -379,7 +386,7 @@ public class PdfUtils {
      * @return converted document to PDF-Image
      * @throws IOException if conversion fails
      */
-    public static PDDocument convertPdfToPdfImage(PDDocument document) throws IOException {
+    public PDDocument convertPdfToPdfImage(PDDocument document) throws IOException {
         PDDocument imageDocument = new PDDocument();
         PDFRenderer pdfRenderer = new PDFRenderer(document);
         pdfRenderer.setSubsamplingAllowed(true);
@@ -428,8 +435,7 @@ public class PdfUtils {
         return imageDocument;
     }
 
-    private static BufferedImage prepareImageForPdfToImage(
+    private BufferedImage prepareImageForPdfToImage(int maxWidth, int height, String imageType) {
-            int maxWidth, int height, String imageType) {
         BufferedImage combined;
         if ("png".equalsIgnoreCase(imageType)) {
             combined = new BufferedImage(maxWidth, height, BufferedImage.TYPE_INT_ARGB);
@@ -445,7 +451,7 @@ public class PdfUtils {
         return combined;
     }
 
-    public static byte[] imageToPdf(
+    public byte[] imageToPdf(
             MultipartFile[] files,
             String fitOption,
             boolean autoRotate,
@@ -489,7 +495,7 @@ public class PdfUtils {
         }
     }
 
-    public static void addImageToDocument(
+    public void addImageToDocument(
             PDDocument doc, PDImageXObject image, String fitOption, boolean autoRotate)
             throws IOException {
         boolean imageIsLandscape = image.getWidth() > image.getHeight();
@@ -539,7 +545,7 @@ public class PdfUtils {
         }
     }
 
-    public static byte[] overlayImage(
+    public byte[] overlayImage(
             CustomPDFDocumentFactory pdfDocumentFactory,
             byte[] pdfBytes,
             byte[] imageBytes,
@@ -586,8 +592,11 @@ public class PdfUtils {
         if (pagesToCheck == null || "all".equals(pagesToCheck)) {
             pdfText = new StringBuilder(textStripper.getText(pdfDocument));
         } else {
-            // remove whitespaces
+            // remove whitespaces using cached pattern
-            pagesToCheck = pagesToCheck.replaceAll("\\s+", "");
+            Pattern whitespacePattern =
+                    patternCache.getPattern(RegexPatternUtils.getWhitespaceRegex());
+            Matcher whitespaceMatcher = whitespacePattern.matcher(pagesToCheck);
+            pagesToCheck = whitespaceMatcher.replaceAll("");
 
             String[] splitPoints = pagesToCheck.split(",");
             for (String splitPoint : splitPoints) {

app/common/src/main/java/stirling/software/common/util/RegexPatternUtils.java

@@ -0,0 +1,506 @@
+package stirling.software.common.util;
+
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.regex.Pattern;
+import java.util.regex.PatternSyntaxException;
+
+import lombok.extern.slf4j.Slf4j;
+
+@Slf4j
+public final class RegexPatternUtils {
+
+    private static final RegexPatternUtils INSTANCE = new RegexPatternUtils();
+    private final ConcurrentHashMap<PatternKey, Pattern> patternCache = new ConcurrentHashMap<>();
+
+    private static final String WHITESPACE_REGEX = "\\s++";
+    private static final String EXTENSION_REGEX = "\\.(?:[^.]*+)?$";
+
+    private RegexPatternUtils() {
+        super();
+        // Initialize with commonly used patterns for immediate availability
+        precompileCommonPatterns();
+    }
+
+    /**
+     * Get the singleton instance of the pattern cache.
+     *
+     * @return the singleton RegexPatternCache instance
+     */
+    public static RegexPatternUtils getInstance() {
+        return INSTANCE;
+    }
+
+    /**
+     * Get a compiled pattern from cache, compiling and caching if not present.
+     *
+     * <p>This method is thread-safe and uses lazy initialization. Multiple threads calling with the
+     * same regex will result in only one compilation, with all threads receiving the same cached
+     * Pattern instance.
+     *
+     * <p>Performance: first call compiles and caches (expensive), subsequent calls return cached
+     * pattern (fast O(1) lookup).
+     *
+     * @param regex the regular expression string to compile
+     * @return compiled Pattern object, never null
+     * @throws PatternSyntaxException if the regex syntax is invalid
+     * @throws IllegalArgumentException if regex is null
+     */
+    public Pattern getPattern(String regex) {
+        if (regex == null) {
+            throw new IllegalArgumentException("Regex pattern cannot be null");
+        }
+
+        return patternCache.computeIfAbsent(new PatternKey(regex, 0), this::compilePattern);
+    }
+
+    /**
+     * Get a compiled pattern with flags.
+     *
+     * <p>Patterns with different flags are cached separately using a composite key. Common flags
+     * include:
+     *
+     * <ul>
+     *   <li>{@link Pattern#CASE_INSENSITIVE} - ignore case differences
+     *   <li>{@link Pattern#MULTILINE} - ^ and $ match line boundaries
+     *   <li>{@link Pattern#DOTALL} - . matches any character including newlines
+     * </ul>
+     *
+     * @param regex the regular expression string
+     * @param flags pattern flags (e.g., Pattern.CASE_INSENSITIVE)
+     * @return compiled Pattern object with specified flags
+     * @throws PatternSyntaxException if the regex syntax is invalid
+     * @throws IllegalArgumentException if regex is null
+     */
+    public Pattern getPattern(String regex, int flags) {
+        if (regex == null) {
+            throw new IllegalArgumentException("Regex pattern cannot be null");
+        }
+
+        return patternCache.computeIfAbsent(new PatternKey(regex, flags), this::compilePattern);
+    }
+
+    /**
+     * Check if a pattern is already cached.
+     *
+     * @param regex the regular expression string
+     * @return true if pattern is cached, false otherwise
+     */
+    public boolean isCached(String regex) {
+        return isCached(regex, 0);
+    }
+
+    /**
+     * Check if a pattern with flags is already cached.
+     *
+     * @param regex the regular expression string
+     * @param flags pattern flags
+     * @return true if pattern is cached, false otherwise
+     */
+    public boolean isCached(String regex, int flags) {
+        return regex != null && patternCache.containsKey(new PatternKey(regex, flags));
+    }
+
+    /**
+     * Get current cache size (number of cached patterns). Useful for monitoring and debugging.
+     *
+     * @return number of patterns currently cached
+     */
+    public int getCacheSize() {
+        return patternCache.size();
+    }
+
+    /**
+     * Clear all cached patterns. Use sparingly as it forces recompilation of all patterns. Mainly
+     * useful for testing or memory cleanup in long-running applications.
+     */
+    public void clearCache() {
+        patternCache.clear();
+        log.debug("Regex pattern cache cleared");
+    }
+
+    /**
+     * Remove a specific pattern from cache.
+     *
+     * @param regex the regular expression string to remove
+     * @return true if pattern was cached and removed, false otherwise
+     */
+    public boolean removeFromCache(String regex) {
+        return removeFromCache(regex, 0);
+    }
+
+    /**
+     * Remove a specific pattern with flags from cache.
+     *
+     * @param regex the regular expression string to remove
+     * @param flags pattern flags
+     * @return true if pattern was cached and removed, false otherwise
+     */
+    public boolean removeFromCache(String regex, int flags) {
+        if (regex == null) {
+            return false;
+        }
+        PatternKey key = new PatternKey(regex, flags);
+        boolean removed = patternCache.remove(key) != null;
+        if (removed) {
+            log.debug("Removed regex pattern from cache: {} (flags: {})", regex, flags);
+        }
+        return removed;
+    }
+
+    /**
+     * Internal method to compile a pattern and handle errors consistently.
+     *
+     * @return compiled Pattern
+     * @throws PatternSyntaxException if regex is invalid
+     */
+    private Pattern compilePattern(PatternKey key) {
+        String regex = key.regex;
+        int flags = key.flags;
+
+        try {
+            Pattern pattern = Pattern.compile(regex, flags);
+            log.trace("Compiled and cached regex pattern with flags {}: {}", flags, regex);
+            return pattern;
+        } catch (PatternSyntaxException e) {
+            log.error(
+                    "Invalid regex pattern: '{}' with flags {} - {}", regex, flags, e.getMessage());
+            throw e;
+        }
+    }
+
+    public static String getWhitespaceRegex() {
+        return WHITESPACE_REGEX;
+    }
+
+    /** Creates a case-insensitive pattern for text searching */
+    public Pattern createSearchPattern(String regex, boolean caseInsensitive) {
+        int flags = caseInsensitive ? (Pattern.CASE_INSENSITIVE | Pattern.UNICODE_CASE) : 0;
+        return getPattern(regex, flags);
+    }
+
+    /** Pattern for matching trailing slashes (e.g., "/path/to/dir///") */
+    public Pattern getTrailingSlashesPattern() {
+        return getPattern("/+$");
+    }
+
+    /** Pattern for removing drive letters from paths */
+    public Pattern getDriveLetterPattern() {
+        return getPattern("^[a-zA-Z]:[\\\\/]+");
+    }
+
+    /** Pattern for removing leading slashes from paths */
+    public Pattern getLeadingSlashesPattern() {
+        return getPattern("^[\\\\/]+");
+    }
+
+    /** Pattern for matching backslashes */
+    public Pattern getBackslashPattern() {
+        return getPattern("\\\\");
+    }
+
+    /** Pattern for sanitizing filenames by removing problematic characters */
+    public Pattern getSafeFilenamePattern() {
+        return getPattern("[/\\\\?%*:|\"<>]");
+    }
+
+    /** Pattern for sanitizing filenames (keeps only alphanumeric) */
+    public Pattern getFilenameSafePattern() {
+        return getPattern("[^a-zA-Z0-9]");
+    }
+
+    /**
+     * Pattern for replacing non-alphanumeric characters with underscore (explicit underscore
+     * variant)
+     */
+    public Pattern getNonAlnumUnderscorePattern() {
+        return getPattern("[^A-Za-z0-9_]");
+    }
+
+    /** Pattern for collapsing multiple underscores */
+    public Pattern getMultipleUnderscoresPattern() {
+        return getPattern("_+");
+    }
+
+    /** Pattern for trimming leading underscores */
+    public Pattern getLeadingUnderscoresPattern() {
+        return getPattern("^_+");
+    }
+
+    /** Pattern for trimming trailing underscores */
+    public Pattern getTrailingUnderscoresPattern() {
+        return getPattern("_+$");
+    }
+
+    /** Pattern for matching upload/download paths (case insensitive) */
+    public Pattern getUploadDownloadPathPattern() {
+        return getPattern("(?i).*/(upload|download)/.*");
+    }
+
+    /** Pattern for matching one or more whitespace characters */
+    public Pattern getWhitespacePattern() {
+        return getPattern("\\s+");
+    }
+
+    /** Pattern for matching newlines (Windows and Unix style) */
+    public Pattern getNewlinesPattern() {
+        return getPattern("\\r?\\n");
+    }
+
+    /** Pattern for splitting on newlines (Windows and Unix style) */
+    public Pattern getNewlineSplitPattern() {
+        return getPattern("\\r?\\n");
+    }
+
+    /** Pattern for splitting text into words */
+    public Pattern getWordSplitPattern() {
+        return getPattern("\\s+");
+    }
+
+    /** Pattern for removing carriage returns */
+    public Pattern getCarriageReturnPattern() {
+        return getPattern("\\r");
+    }
+
+    /** Pattern for matching newline characters */
+    public Pattern getNewlineCharsPattern() {
+        return getPattern("[\n\r]");
+    }
+
+    /** Pattern for multi-format newline splitting (Windows, Mac, Unix) */
+    public Pattern getMultiFormatNewlinePattern() {
+        return getPattern("\r\n|\r|\n");
+    }
+
+    /** Pattern for encoded payload newline removal */
+    public Pattern getEncodedPayloadNewlinePattern() {
+        return getPattern("\\r?\\n");
+    }
+
+    /** Pattern for escaped newlines in watermark text */
+    public Pattern getEscapedNewlinePattern() {
+        return getPattern("\\\\n");
+    }
+
+    /** Pattern for input sanitization (allows only alphanumeric and spaces) */
+    public Pattern getInputSanitizePattern() {
+        return getPattern("[^a-zA-Z0-9 ]");
+    }
+
+    /** Pattern for removing angle brackets */
+    public Pattern getAngleBracketsPattern() {
+        return getPattern("[<>]");
+    }
+
+    /** Pattern for removing leading and trailing quotes */
+    public Pattern getQuotesRemovalPattern() {
+        return getPattern("^\"|\"$");
+    }
+
+    /** Pattern for plus signs (URL encoding replacement) */
+    public Pattern getPlusSignPattern() {
+        return getPattern("\\+");
+    }
+
+    /** Pattern for username validation */
+    public Pattern getUsernameValidationPattern() {
+        return getPattern("^[a-zA-Z0-9](?!.*[-@._+]{2,})[a-zA-Z0-9@._+-]{1,48}[a-zA-Z0-9]$");
+    }
+
+    public static String getExtensionRegex() {
+        return EXTENSION_REGEX;
+    }
+
+    /** Pattern for extracting non-numeric characters */
+    public Pattern getNumericExtractionPattern() {
+        return getPattern("\\D");
+    }
+
+    /** Pattern for removing non-digit/dot characters (for timeout parsing) */
+    public Pattern getNonDigitDotPattern() {
+        return getPattern("[^\\d.]");
+    }
+
+    /** Pattern for matching digit/dot characters (for timeout parsing) */
+    public Pattern getDigitDotPattern() {
+        return getPattern("[\\d.]");
+    }
+
+    /** Pattern for detecting strings containing digits */
+    public Pattern getContainsDigitsPattern() {
+        return getPattern(".*\\d+.*");
+    }
+
+    /** Pattern for matching 1-3 digit numbers */
+    public Pattern getNumberRangePattern() {
+        return getPattern("[1-9][0-9]{0,2}");
+    }
+
+    /** Pattern for validating mathematical expressions */
+    public Pattern getMathExpressionPattern() {
+        return getPattern("[0-9n+\\-*/() ]+");
+    }
+
+    /** Pattern for adding multiplication between numbers and 'n' */
+    public Pattern getNumberBeforeNPattern() {
+        return getPattern("(\\d)n");
+    }
+
+    /** Pattern for detecting consecutive 'n' characters */
+    public Pattern getConsecutiveNPattern() {
+        return getPattern(".*n{2,}.*");
+    }
+
+    /** Pattern for replacing consecutive 'n' characters */
+    public Pattern getConsecutiveNReplacementPattern() {
+        return getPattern("(?<!n)n{2}");
+    }
+
+    /** Pattern for validating HTTP/HTTPS URLs */
+    public Pattern getHttpUrlPattern() {
+        return getPattern("^https?://.*");
+    }
+
+    /** Pattern for matching URLs in text for link creation */
+    public Pattern getUrlLinkPattern() {
+        return getPattern("(https?://[\\w\\-._~:/?#\\[\\]@!$&'()*+,;=%]+)");
+    }
+
+    /** Pattern for matching email addresses in text for link creation */
+    public Pattern getEmailLinkPattern() {
+        return getPattern("([a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\\.[a-zA-Z]{2,63})");
+    }
+
+    /** Pattern for removing script tags from HTML */
+    public Pattern getScriptTagPattern() {
+        return getPattern("(?i)<script[^>]*>.*?</script>");
+    }
+
+    /** Pattern for removing style tags from HTML */
+    public Pattern getStyleTagPattern() {
+        return getPattern("(?i)<style[^>]*>.*?</style>");
+    }
+
+    /** Pattern for removing fixed position CSS */
+    public Pattern getFixedPositionCssPattern() {
+        return getPattern("(?i)\\s*position\\s*:\\s*fixed[^;]*;?");
+    }
+
+    /** Pattern for removing absolute position CSS */
+    public Pattern getAbsolutePositionCssPattern() {
+        return getPattern("(?i)\\s*position\\s*:\\s*absolute[^;]*;?");
+    }
+
+    /** Pattern for matching size unit suffixes (KB, MB, GB, etc.) */
+    public Pattern getSizeUnitPattern() {
+        return getPattern("[KMGkmg][Bb]");
+    }
+
+    /** Pattern for system temp file type 1 */
+    public Pattern getSystemTempFile1Pattern() {
+        return getPattern("lu\\d+[a-z0-9]*\\.tmp");
+    }
+
+    /** Pattern for system temp file type 2 (OCR processes) */
+    public Pattern getSystemTempFile2Pattern() {
+        return getPattern("ocr_process\\d+");
+    }
+
+    /** Pattern for splitting on whitespace and parentheses */
+    public Pattern getWhitespaceParenthesesSplitPattern() {
+        return getPattern("[\\s\\(\\)]+");
+    }
+
+    /** Pattern for MIME header whitespace cleanup before encoded sequences */
+    public Pattern getMimeHeaderWhitespacePattern() {
+        return getPattern("\\s+(?==\\?)");
+    }
+
+    /** Pattern for font name validation (6 uppercase letters + plus + rest) */
+    public Pattern getFontNamePattern() {
+        return getPattern("^[A-Z]{6}\\+.*");
+    }
+
+    /** Pattern for matching access="readOnly" attribute in XFA XML (with optional whitespace) */
+    public Pattern getAccessReadOnlyPattern() {
+        return getPattern("access\\s*=\\s*\"readOnly\"");
+    }
+
+    /** Pattern for matching MIME encoded-word headers (RFC 2047) Example: =?charset?B?encoded?= */
+    public Pattern getMimeEncodedWordPattern() {
+        return getPattern("=\\?([^?]+)\\?([BbQq])\\?([^?]*)\\?=");
+    }
+
+    /** Pattern for matching inline CID images in HTML (case-insensitive) */
+    public Pattern getInlineCidImagePattern() {
+        return getPattern(
+                "(?i)<img[^>]*\\ssrc\\s*=\\s*['\"]cid:([^'\"]+)['\"][^>]*>",
+                Pattern.CASE_INSENSITIVE);
+    }
+
+    /** Pattern for matching attachment section headers (case-insensitive) */
+    public Pattern getAttachmentSectionPattern() {
+        return getPattern("attachments\\s*\\(\\d+\\)", Pattern.CASE_INSENSITIVE);
+    }
+
+    /** Pattern for matching filenames in attachment markers */
+    public Pattern getAttachmentFilenamePattern() {
+        return getPattern("@\\s*([^\\s\\(]+(?:\\.[a-zA-Z0-9]+)?)");
+    }
+
+    // API doc parsing patterns
+
+    /**
+     * Pre-compile commonly used patterns for immediate availability. This eliminates first-call
+     * compilation overhead for frequent patterns.
+     */
+    private void precompileCommonPatterns() {
+        getPattern("\\.(?:[^.]*+)?$"); // Extension removal - possessive, optional, anchored
+        getPattern("\\.[^.]+$"); // Simple extension match - anchored
+
+        getPattern("\\s+"); // One or more whitespace
+        getPattern("\\s*"); // Zero or more whitespace
+
+        getPattern("/+$"); // Trailing slashes
+        getPattern("\\D"); // Non-numeric characters
+        getPattern("[/\\\\?%*:|\"<>]"); // Unsafe filename characters
+        getPattern("[^a-zA-Z0-9 ]"); // Input sanitization
+        getPattern("[^a-zA-Z0-9]"); // Filename sanitization
+        // API doc patterns
+        getPattern("Output:(\\w+)"); // precompiled single-escaped for runtime regex \w
+        getPattern("Input:(\\w+)");
+        getPattern("Type:(\\w+)");
+        log.debug("Pre-compiled {} common regex patterns", patternCache.size());
+    }
+
+    /** Pattern for email validation */
+    public Pattern getEmailValidationPattern() {
+        return getPattern(
+                "^(?=.{1,320}$)(?=.{1,64}@)[A-Za-z0-9](?:[A-Za-z0-9_.+-]*[A-Za-z0-9])?@[^-][A-Za-z0-9-]+(?:\\.[A-Za-z0-9-]+)*(?:\\.[A-Za-z]{2,})$");
+    }
+
+    /* Pattern for matching Output:<TYPE> in API descriptions */
+    public Pattern getApiDocOutputTypePattern() {
+        return getPattern("Output:(\\w+)");
+    }
+
+    /* Pattern for matching Input:<TYPE> in API descriptions */
+    public Pattern getApiDocInputTypePattern() {
+        return getPattern("Input:(\\w+)");
+    }
+
+    /**
+     * Pattern for matching Type:<CODE> in API descriptions
+     */
+    public Pattern getApiDocTypePattern() {
+        return getPattern("Type:(\\w+)");
+    }
+
+    /* Pattern for validating file extensions (2-4 alphanumeric, case-insensitive) */
+    public Pattern getFileExtensionValidationPattern() {
+        return getPattern("^[a-zA-Z0-9]{2,4}$", Pattern.CASE_INSENSITIVE);
+    }
+
+    private record PatternKey(String regex, int flags) {
+        // Record automatically provides equals, hashCode, and toString
+    }
+}

app/common/src/main/java/stirling/software/common/util/WebResponseUtils.java

@@ -50,7 +50,10 @@ public class WebResponseUtils {
         headers.setContentType(mediaType);
         headers.setContentLength(bytes.length);
         String encodedDocName =
-                URLEncoder.encode(docName, StandardCharsets.UTF_8).replaceAll("\\+", "%20");
+                RegexPatternUtils.getInstance()
+                        .getPlusSignPattern()
+                        .matcher(URLEncoder.encode(docName, StandardCharsets.UTF_8))
+                        .replaceAll("%20");
         headers.setContentDispositionFormData("attachment", encodedDocName);
         return new ResponseEntity<>(bytes, headers, HttpStatus.OK);
     }

app/common/src/test/java/stirling/software/common/model/ApplicationPropertiesLogicTest.java

@@ -14,6 +14,7 @@ import stirling.software.common.model.ApplicationProperties.Driver;
 import stirling.software.common.model.ApplicationProperties.Premium;
 import stirling.software.common.model.ApplicationProperties.Security;
 import stirling.software.common.model.exception.UnsupportedProviderException;
+import stirling.software.common.util.RegexPatternUtils;
 
 class ApplicationPropertiesLogicTest {
 
@@ -38,7 +39,10 @@ class ApplicationPropertiesLogicTest {
                 new ApplicationProperties.TempFileManagement();
 
         String expectedBase =
-                java.lang.System.getProperty("java.io.tmpdir").replaceAll("/+$", "")
+                RegexPatternUtils.getInstance()
+                                .getTrailingSlashesPattern()
+                                .matcher(java.lang.System.getProperty("java.io.tmpdir"))
+                                .replaceAll("")
                         + "/stirling-pdf";
         assertEquals(expectedBase, normalize.apply(tfm.getBaseTmpDir()));
 

app/common/src/test/java/stirling/software/common/util/GeneralUtilsTest.java

@@ -1,8 +1,15 @@
 package stirling.software.common.util;
 
-import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.*;
 
+import java.util.ArrayList;
+import java.util.Collections;
 import java.util.List;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicInteger;
 
 import org.junit.jupiter.api.Test;
 
@@ -154,4 +161,223 @@ public class GeneralUtilsTest {
         List<Integer> result = GeneralUtils.parsePageList(new String[] {"1,3,7-8"}, 8, false);
         assertEquals(List.of(0, 2, 6, 7), result, "Range should be parsed correctly.");
     }
+
+    @Test
+    void testRemoveExtension() {
+        // Test common cases (should use fast string operations)
+        assertEquals("document", GeneralUtils.removeExtension("document.pdf"));
+        assertEquals("image", GeneralUtils.removeExtension("image.jpg"));
+        assertEquals("file.backup", GeneralUtils.removeExtension("file.backup.zip"));
+        assertEquals("complex.file.name", GeneralUtils.removeExtension("complex.file.name.txt"));
+
+        // Test edge cases (should fall back to regex)
+        assertEquals("default", GeneralUtils.removeExtension(null));
+        assertEquals("noextension", GeneralUtils.removeExtension("noextension"));
+        assertEquals(
+                ".hidden", GeneralUtils.removeExtension(".hidden")); // Hidden file, no extension
+        assertEquals("trailing.", GeneralUtils.removeExtension("trailing.")); // Trailing dot
+        assertEquals("", GeneralUtils.removeExtension(""));
+        assertEquals("a", GeneralUtils.removeExtension("a"));
+
+        // Test multiple dots
+        assertEquals("file.with.multiple", GeneralUtils.removeExtension("file.with.multiple.dots"));
+        assertEquals("path/to/file", GeneralUtils.removeExtension("path/to/file.ext"));
+    }
+
+    @Test
+    void testAppendSuffix() {
+        // Normal cases
+        assertEquals("document_processed", GeneralUtils.appendSuffix("document", "_processed"));
+        assertEquals("file.txt", GeneralUtils.appendSuffix("file", ".txt"));
+
+        // Null handling
+        assertEquals("default_suffix", GeneralUtils.appendSuffix(null, "_suffix"));
+        assertEquals("basename", GeneralUtils.appendSuffix("basename", null));
+        assertEquals("default", GeneralUtils.appendSuffix(null, null));
+
+        // Empty strings
+        assertEquals("_suffix", GeneralUtils.appendSuffix("", "_suffix"));
+        assertEquals("basename", GeneralUtils.appendSuffix("basename", ""));
+    }
+
+    @Test
+    void testProcessFilenames() {
+        List<String> filenames = new ArrayList<>();
+        filenames.add("document.pdf");
+        filenames.add("image.jpg");
+        filenames.add("spreadsheet.xlsx");
+        filenames.add("presentation.pptx");
+        filenames.add(null); // Should handle null gracefully
+        filenames.add("noextension");
+
+        List<String> results = new ArrayList<>();
+        GeneralUtils.processFilenames(filenames, "_processed", results::add);
+
+        List<String> expected =
+                List.of(
+                        "document_processed",
+                        "image_processed",
+                        "spreadsheet_processed",
+                        "presentation_processed",
+                        "default_processed",
+                        "noextension_processed");
+
+        assertEquals(expected, results);
+    }
+
+    @Test
+    void testProcessFilenamesNullHandling() {
+        List<String> results = new ArrayList<>();
+
+        // Null filenames list
+        GeneralUtils.processFilenames(null, "_suffix", results::add);
+        assertTrue(results.isEmpty(), "Should handle null filenames list");
+
+        // Null processor
+        List<String> filenames = List.of("test.txt");
+        GeneralUtils.processFilenames(filenames, "_suffix", null); // Should not throw
+    }
+
+    @Test
+    void testRemoveExtensionThreadSafety() throws InterruptedException {
+        final int threadCount = 50;
+        final int operationsPerThread = 100;
+        final String[] testFilenames = {
+            "document.pdf", "image.jpg", "data.csv", "presentation.pptx",
+            "archive.zip", "music.mp3", "video.mp4", "text.txt"
+        };
+
+        ExecutorService executor = Executors.newFixedThreadPool(threadCount);
+        CountDownLatch latch = new CountDownLatch(threadCount);
+        AtomicInteger successCount = new AtomicInteger(0);
+        List<Exception> exceptions = Collections.synchronizedList(new ArrayList<>());
+
+        for (int i = 0; i < threadCount; i++) {
+            executor.submit(
+                    () -> {
+                        try {
+                            for (int j = 0; j < operationsPerThread; j++) {
+                                String filename = testFilenames[j % testFilenames.length];
+                                String result = GeneralUtils.removeExtension(filename);
+
+                                // Verify result is correct
+                                assertFalse(
+                                        result.contains("."),
+                                        "Result should not contain extension: " + result);
+                                assertTrue(
+                                        filename.startsWith(result),
+                                        "Original should start with result: "
+                                                + filename
+                                                + " -> "
+                                                + result);
+                            }
+                            successCount.incrementAndGet();
+                        } catch (Exception e) {
+                            exceptions.add(e);
+                        } finally {
+                            latch.countDown();
+                        }
+                    });
+        }
+
+        assertTrue(latch.await(10, TimeUnit.SECONDS), "All threads should complete");
+
+        if (!exceptions.isEmpty()) {
+            fail("Thread safety test failed with exceptions: " + exceptions);
+        }
+
+        assertEquals(threadCount, successCount.get(), "All threads should succeed");
+
+        executor.shutdown();
+    }
+
+    @Test
+    void testBatchProcessingPerformance() {
+        List<String> filenames = new ArrayList<>();
+        for (int i = 0; i < 1000; i++) {
+            filenames.add("file" + i + ".pdf");
+            filenames.add("document" + i + ".docx");
+            filenames.add("image" + i + ".jpg");
+        }
+
+        List<String> results = new ArrayList<>();
+
+        GeneralUtils.processFilenames(filenames, "_processed", results::add);
+
+        assertEquals(filenames.size(), results.size(), "Should process all filenames");
+
+        assertTrue(results.contains("file0_processed"), "Should contain processed filename");
+        assertTrue(results.contains("document500_processed"), "Should contain processed filename");
+        assertTrue(results.contains("image999_processed"), "Should contain processed filename");
+    }
+
+    @Test
+    void testHybridStringRegexApproach() {
+
+        String[] edgeCases = {
+            "", // Empty string
+            ".", // Just a dot
+            "..", // Two dots
+            "...", // Three dots
+            ".hidden", // Hidden file
+            "file.", // Trailing dot
+            "a.b.c.d.e.f.g", // Many extensions
+            "no-extension-here", // No extension
+            "file..double.dot" // Double dots
+        };
+
+        for (String edgeCase : edgeCases) {
+            String result = GeneralUtils.removeExtension(edgeCase);
+            assertNotNull(result, "Result should not be null for: " + edgeCase);
+
+            // For specific edge cases, verify expected behavior
+            switch (edgeCase) {
+                case "" -> assertEquals("", result, "Empty string should remain empty");
+                case "." -> assertEquals(".", result, "Single dot should remain unchanged");
+                case ".." -> assertEquals("..", result, "Double dots should remain unchanged");
+                case "..." -> assertEquals("...", result, "Triple dots should remain unchanged");
+                case ".hidden" ->
+                        assertEquals(".hidden", result, "Hidden file should remain unchanged");
+                case "file." ->
+                        assertEquals("file.", result, "Trailing dot should remain unchanged");
+                case "no-extension-here" ->
+                        assertEquals(
+                                "no-extension-here",
+                                result,
+                                "No extension should remain unchanged");
+                case "a.b.c.d.e.f.g" ->
+                        assertEquals(
+                                "a.b.c.d.e.f",
+                                result,
+                                "Multiple extensions should remove last one");
+                case "file..double.dot" ->
+                        assertEquals(
+                                "file..double",
+                                result,
+                                "Double dot case should remove last extension");
+            }
+        }
+    }
+
+    @Test
+    void testGetTitleFromFilename() {
+        // Test normal cases
+        assertEquals("document", GeneralUtils.getTitleFromFilename("document.pdf"));
+        assertEquals("presentation", GeneralUtils.getTitleFromFilename("presentation.pptx"));
+        assertEquals("file.backup", GeneralUtils.getTitleFromFilename("file.backup.zip"));
+
+        // Test null and empty handling
+        assertEquals("Untitled", GeneralUtils.getTitleFromFilename(null));
+        assertEquals("Untitled", GeneralUtils.getTitleFromFilename(""));
+
+        // Test edge cases
+        assertEquals(".hidden", GeneralUtils.getTitleFromFilename(".hidden"));
+        assertEquals("file.", GeneralUtils.getTitleFromFilename("file."));
+        assertEquals("noextension", GeneralUtils.getTitleFromFilename("noextension"));
+
+        // Test complex cases
+        assertEquals(
+                "complex.file.name", GeneralUtils.getTitleFromFilename("complex.file.name.txt"));
+        assertEquals("path/to/file", GeneralUtils.getTitleFromFilename("path/to/file.ext"));
+    }
 }

app/common/src/test/java/stirling/software/common/util/PdfUtilsTest.java

@@ -65,23 +65,22 @@ public class PdfUtilsTest {
         doc1.addPage(new PDPage());
         doc1.addPage(new PDPage());
         doc1.addPage(new PDPage());
-        PdfUtils utils = new PdfUtils();
+        assertTrue(PdfUtils.pageCount(doc1, 2, "greater"));
-        assertTrue(utils.pageCount(doc1, 2, "greater"));
 
         PDDocument doc2 = new PDDocument();
         doc2.addPage(new PDPage());
         doc2.addPage(new PDPage());
         doc2.addPage(new PDPage());
-        assertTrue(utils.pageCount(doc2, 3, "equal"));
+        assertTrue(PdfUtils.pageCount(doc2, 3, "equal"));
 
         PDDocument doc3 = new PDDocument();
         doc3.addPage(new PDPage());
         doc3.addPage(new PDPage());
-        assertTrue(utils.pageCount(doc3, 5, "less"));
+        assertTrue(PdfUtils.pageCount(doc3, 5, "less"));
 
         PDDocument doc4 = new PDDocument();
         doc4.addPage(new PDPage());
-        assertThrows(IllegalArgumentException.class, () -> utils.pageCount(doc4, 1, "bad"));
+        assertThrows(IllegalArgumentException.class, () -> PdfUtils.pageCount(doc4, 1, "bad"));
     }
 
     @Test
@@ -91,8 +90,7 @@ public class PdfUtilsTest {
         doc.addPage(page);
         PDRectangle rect = page.getMediaBox();
         String expected = rect.getWidth() + "x" + rect.getHeight();
-        PdfUtils utils = new PdfUtils();
+        assertTrue(PdfUtils.pageSize(doc, expected));
-        assertTrue(utils.pageSize(doc, expected));
     }
 
     @Test

app/common/src/test/java/stirling/software/common/util/RegexPatternUtilsTest.java

@@ -0,0 +1,115 @@
+package stirling.software.common.util;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+import java.util.regex.Pattern;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+public class RegexPatternUtilsTest {
+
+    private RegexPatternUtils utils;
+
+    @BeforeEach
+    void setUp() {
+        utils = RegexPatternUtils.getInstance();
+        utils.clearCache(); // Start with clean cache for each test
+    }
+
+    @Test
+    void testPatternCaching() {
+        String regex = "test\\d+";
+
+        Pattern pattern1 = utils.getPattern(regex);
+        assertNotNull(pattern1);
+        assertTrue(utils.isCached(regex));
+        assertEquals(
+                1, utils.getCacheSize()); // Should have at least 1 pattern (plus precompiled ones
+        // are cleared)
+
+        Pattern pattern2 = utils.getPattern(regex);
+        assertSame(pattern1, pattern2); // Should be the exact same object
+    }
+
+    @Test
+    void testPatternWithFlags() {
+        String regex = "test";
+        int flags = Pattern.CASE_INSENSITIVE;
+
+        Pattern pattern1 = utils.getPattern(regex, flags);
+        Pattern pattern2 = utils.getPattern(regex); // No flags
+
+        assertNotSame(pattern1, pattern2); // Different flags = different cached patterns
+        assertTrue(utils.isCached(regex, flags));
+        assertTrue(utils.isCached(regex, 0));
+    }
+
+    @Test
+    void testCacheEviction() {
+        String regex = "evict\\d+";
+
+        utils.getPattern(regex);
+        assertTrue(utils.isCached(regex));
+
+        boolean removed = utils.removeFromCache(regex);
+        assertTrue(removed);
+        assertFalse(utils.isCached(regex));
+
+        boolean removedAgain = utils.removeFromCache(regex);
+        assertFalse(removedAgain);
+    }
+
+    @Test
+    void testNullRegexHandling() {
+        assertThrows(
+                IllegalArgumentException.class,
+                () -> {
+                    utils.getPattern(null);
+                });
+
+        assertThrows(
+                IllegalArgumentException.class,
+                () -> {
+                    utils.getPattern(null, Pattern.CASE_INSENSITIVE);
+                });
+
+        assertFalse(utils.isCached(null));
+        assertFalse(utils.removeFromCache(null));
+    }
+
+    @Test
+    void testCommonPatterns() {
+        Pattern whitespace = utils.getWhitespacePattern();
+        assertTrue(whitespace.matcher("  \t  ").matches());
+
+        Pattern trailing = utils.getTrailingSlashesPattern();
+        assertTrue(trailing.matcher("/path/to/dir///").find());
+
+        Pattern filename = utils.getSafeFilenamePattern();
+        assertTrue(filename.matcher("bad<file>name").find());
+    }
+
+    @Test
+    void testCreateSearchPattern() {
+        String regex = "Hello";
+
+        Pattern caseSensitive = utils.createSearchPattern(regex, false);
+        Pattern caseInsensitive = utils.createSearchPattern(regex, true);
+
+        assertTrue(caseSensitive.matcher("Hello").matches());
+        assertFalse(caseSensitive.matcher("hello").matches());
+
+        assertTrue(caseInsensitive.matcher("Hello").matches());
+        assertTrue(caseInsensitive.matcher("hello").matches());
+        assertTrue(caseInsensitive.matcher("HELLO").matches());
+    }
+
+    @Test
+    void testSingletonBehavior() {
+        RegexPatternUtils instance1 = RegexPatternUtils.getInstance();
+        RegexPatternUtils instance2 = RegexPatternUtils.getInstance();
+
+        assertSame(instance1, instance2);
+    }
+}

app/core/src/main/java/stirling/software/SPDF/UI/impl/LoadingWindow.java

@@ -7,6 +7,7 @@ import java.io.InputStreamReader;
 import java.util.HashSet;
 import java.util.Set;
 import java.util.concurrent.TimeUnit;
+import java.util.regex.Pattern;
 
 import javax.imageio.ImageIO;
 import javax.swing.*;
@@ -15,10 +16,13 @@ import io.github.pixee.security.BoundedLineReader;
 
 import lombok.extern.slf4j.Slf4j;
 
+import stirling.software.common.util.RegexPatternUtils;
 import stirling.software.common.util.UIScaling;
 
 @Slf4j
 public class LoadingWindow extends JDialog {
+    private static final Pattern PATTERN =
+            RegexPatternUtils.getInstance().getContainsDigitsPattern();
     private final JProgressBar progressBar;
     private final JLabel statusLabel;
     private final JPanel mainPanel;
@@ -151,7 +155,10 @@ public class LoadingWindow extends JDialog {
                                                         BoundedLineReader.readLine(
                                                                 reader, 5_000_000))
                                                 != null) {
-                                            if (line.matches(".*\\d+.*")) { // Contains numbers
+                                            if (RegexPatternUtils.getInstance()
+                                                    .getContainsDigitsPattern()
+                                                    .matcher(line)
+                                                    .matches()) { // Contains numbers
                                                 String[] parts = line.trim().split(",");
                                                 if (parts.length >= 2) {
                                                     existingPids.add(
@@ -206,8 +213,8 @@ public class LoadingWindow extends JDialog {
                                                                                                 newReader,
                                                                                                 5_000_000))
                                                                         != null) {
-                                                                    if (newLine.matches(
+                                                                    if (PATTERN.matcher(newLine)
-                                                                            ".*\\d+.*")) {
+                                                                            .matches()) {
                                                                         String[] parts =
                                                                                 newLine.trim()
                                                                                         .split(",");

app/core/src/main/java/stirling/software/SPDF/config/ExternalAppDepConfig.java

@@ -13,6 +13,7 @@ import jakarta.annotation.PostConstruct;
 import lombok.extern.slf4j.Slf4j;
 
 import stirling.software.common.configuration.RuntimePathConfig;
+import stirling.software.common.util.RegexPatternUtils;
 
 @Configuration
 @Slf4j
@@ -73,7 +74,7 @@ public class ExternalAppDepConfig {
         // First replace common terms
         String feature = endpoint.replace("-", " ").replace("pdf", "PDF").replace("img", "image");
         // Split into words and capitalize each word
-        return Arrays.stream(feature.split("\\s+"))
+        return Arrays.stream(RegexPatternUtils.getInstance().getWordSplitPattern().split(feature))
                 .map(word -> capitalizeWord(word))
                 .collect(Collectors.joining(" "));
     }

app/core/src/main/java/stirling/software/SPDF/controller/api/CropController.java

@@ -24,6 +24,7 @@ import lombok.RequiredArgsConstructor;
 
 import stirling.software.SPDF.model.api.general.CropPdfForm;
 import stirling.software.common.service.CustomPDFDocumentFactory;
+import stirling.software.common.util.GeneralUtils;
 import stirling.software.common.util.WebResponseUtils;
 
 @RestController
@@ -93,7 +94,7 @@ public class CropController {
         byte[] pdfContent = baos.toByteArray();
         return WebResponseUtils.bytesToWebResponse(
                 pdfContent,
-                request.getFileInput().getOriginalFilename().replaceFirst("[.][^.]+$", "")
+                GeneralUtils.generateFilename(
-                        + "_cropped.pdf");
+                        request.getFileInput().getOriginalFilename(), "_cropped.pdf"));
     }
 }

app/core/src/main/java/stirling/software/SPDF/controller/api/EditTableOfContentsController.java

@@ -13,12 +13,7 @@ import org.apache.pdfbox.pdmodel.interactive.documentnavigation.outline.PDOutlin
 import org.apache.pdfbox.pdmodel.interactive.documentnavigation.outline.PDOutlineNode;
 import org.springframework.http.MediaType;
 import org.springframework.http.ResponseEntity;
-import org.springframework.web.bind.annotation.ModelAttribute;
+import org.springframework.web.bind.annotation.*;
-import org.springframework.web.bind.annotation.PostMapping;
-import org.springframework.web.bind.annotation.RequestMapping;
-import org.springframework.web.bind.annotation.RequestParam;
-import org.springframework.web.bind.annotation.ResponseBody;
-import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.multipart.MultipartFile;
 
 import com.fasterxml.jackson.core.type.TypeReference;
@@ -34,6 +29,7 @@ import lombok.extern.slf4j.Slf4j;
 
 import stirling.software.SPDF.model.api.EditTableOfContentsRequest;
 import stirling.software.common.service.CustomPDFDocumentFactory;
+import stirling.software.common.util.GeneralUtils;
 import stirling.software.common.util.WebResponseUtils;
 
 @RestController
@@ -182,9 +178,10 @@ public class EditTableOfContentsController {
             ByteArrayOutputStream baos = new ByteArrayOutputStream();
             document.save(baos);
 
-            String filename = file.getOriginalFilename().replaceFirst("[.][^.]+$", "");
             return WebResponseUtils.bytesToWebResponse(
-                    baos.toByteArray(), filename + "_with_toc.pdf", MediaType.APPLICATION_PDF);
+                    baos.toByteArray(),
+                    GeneralUtils.generateFilename(file.getOriginalFilename(), "_with_toc.pdf"),
+                    MediaType.APPLICATION_PDF);
 
         } finally {
             if (document != null) {

app/core/src/main/java/stirling/software/SPDF/controller/api/MergeController.java

@@ -37,6 +37,7 @@ import lombok.extern.slf4j.Slf4j;
 import stirling.software.SPDF.model.api.general.MergePdfsRequest;
 import stirling.software.common.service.CustomPDFDocumentFactory;
 import stirling.software.common.util.ExceptionUtils;
+import stirling.software.common.util.GeneralUtils;
 import stirling.software.common.util.PdfErrorUtils;
 import stirling.software.common.util.TempFile;
 import stirling.software.common.util.TempFileManager;
@@ -127,10 +128,7 @@ public class MergeController {
         for (MultipartFile file : files) {
             // Get the filename without extension to use as bookmark title
             String filename = file.getOriginalFilename();
-            String title = filename;
+            String title = GeneralUtils.removeExtension(filename);
-            if (title != null && title.contains(".")) {
-                title = title.substring(0, title.lastIndexOf('.'));
-            }
 
             // Create an outline item for this file
             PDOutlineItem item = new PDOutlineItem();
@@ -236,10 +234,11 @@ public class MergeController {
             mergedDocument.save(outputTempFile.getFile());
 
             String mergedFileName =
-                    files[0].getOriginalFilename().replaceFirst("[.][^.]+$", "")
+                    GeneralUtils.generateFilename(
-                            + "_merged_unsigned.pdf";
+                            files[0].getOriginalFilename(), "_merged_unsigned.pdf");
             return WebResponseUtils.pdfFileToWebResponse(
-                    outputTempFile, mergedFileName); // Return the modified PDF as stream
+                    outputTempFile, mergedFileName); // Return the modified PDF
+
         } catch (Exception ex) {
             if (ex instanceof IOException && PdfErrorUtils.isCorruptedPdfError((IOException) ex)) {
                 log.warn("Corrupted PDF detected in merge pdf process: {}", ex.getMessage());

app/core/src/main/java/stirling/software/SPDF/controller/api/MultiPageLayoutController.java

@@ -19,7 +19,6 @@ import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.multipart.MultipartFile;
 
-import io.github.pixee.security.Filenames;
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.tags.Tag;
 
@@ -29,6 +28,7 @@ import lombok.extern.slf4j.Slf4j;
 import stirling.software.SPDF.model.api.general.MergeMultiplePagesRequest;
 import stirling.software.common.service.CustomPDFDocumentFactory;
 import stirling.software.common.util.FormUtils;
+import stirling.software.common.util.GeneralUtils;
 import stirling.software.common.util.WebResponseUtils;
 
 @RestController
@@ -166,7 +166,7 @@ public class MultiPageLayoutController {
         byte[] result = baos.toByteArray();
         return WebResponseUtils.bytesToWebResponse(
                 result,
-                Filenames.toSimpleFileName(file.getOriginalFilename()).replaceFirst("[.][^.]+$", "")
+                GeneralUtils.generateFilename(
-                        + "_layoutChanged.pdf");
+                        file.getOriginalFilename(), "_multi_page_layout.pdf"));
     }
 }

app/core/src/main/java/stirling/software/SPDF/controller/api/PdfImageRemovalController.java

@@ -19,6 +19,7 @@ import lombok.RequiredArgsConstructor;
 import stirling.software.SPDF.service.PdfImageRemovalService;
 import stirling.software.common.model.api.PDFFile;
 import stirling.software.common.service.CustomPDFDocumentFactory;
+import stirling.software.common.util.GeneralUtils;
 import stirling.software.common.util.WebResponseUtils;
 
 /**
@@ -69,8 +70,8 @@ public class PdfImageRemovalController {
 
         // Generate a new filename for the modified PDF
         String mergedFileName =
-                file.getFileInput().getOriginalFilename().replaceFirst("[.][^.]+$", "")
+                GeneralUtils.generateFilename(
-                        + "_removed_images.pdf";
+                        file.getFileInput().getOriginalFilename(), "_images_removed.pdf");
 
         // Convert the byte array to a web response and return it
         return WebResponseUtils.bytesToWebResponse(outputStream.toByteArray(), mergedFileName);

app/core/src/main/java/stirling/software/SPDF/controller/api/PdfOverlayController.java

@@ -20,7 +20,6 @@ import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.multipart.MultipartFile;
 
-import io.github.pixee.security.Filenames;
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.tags.Tag;
 
@@ -84,9 +83,8 @@ public class PdfOverlayController {
                 overlay.overlay(overlayGuide).save(outputStream);
                 byte[] data = outputStream.toByteArray();
                 String outputFilename =
-                        Filenames.toSimpleFileName(baseFile.getOriginalFilename())
+                        GeneralUtils.generateFilename(
-                                        .replaceFirst("[.][^.]+$", "")
+                                baseFile.getOriginalFilename(), "_overlayed.pdf");
-                                + "_overlayed.pdf"; // Remove file extension and append .pdf
 
                 return WebResponseUtils.bytesToWebResponse(
                         data, outputFilename, MediaType.APPLICATION_PDF);

app/core/src/main/java/stirling/software/SPDF/controller/api/RearrangePagesPDFController.java

@@ -15,7 +15,6 @@ import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.multipart.MultipartFile;
 
-import io.github.pixee.security.Filenames;
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.tags.Tag;
 
@@ -68,9 +67,7 @@ public class RearrangePagesPDFController {
         }
         return WebResponseUtils.pdfDocToWebResponse(
                 document,
-                Filenames.toSimpleFileName(pdfFile.getOriginalFilename())
+                GeneralUtils.generateFilename(pdfFile.getOriginalFilename(), "_removed_pages.pdf"));
-                                .replaceFirst("[.][^.]+$", "")
-                        + "_removed_pages.pdf");
     }
 
     private List<Integer> removeFirst(int totalPages) {
@@ -286,9 +283,8 @@ public class RearrangePagesPDFController {
 
             return WebResponseUtils.pdfDocToWebResponse(
                     document,
-                    Filenames.toSimpleFileName(pdfFile.getOriginalFilename())
+                    GeneralUtils.generateFilename(
-                                    .replaceFirst("[.][^.]+$", "")
+                            pdfFile.getOriginalFilename(), "_rearranged.pdf"));
-                            + "_rearranged.pdf");
         } catch (IOException e) {
             ExceptionUtils.logException("document rearrangement", e);
             throw e;

app/core/src/main/java/stirling/software/SPDF/controller/api/RotationController.java

@@ -13,7 +13,6 @@ import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.multipart.MultipartFile;
 
-import io.github.pixee.security.Filenames;
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.tags.Tag;
 
@@ -22,6 +21,7 @@ import lombok.RequiredArgsConstructor;
 import stirling.software.SPDF.model.api.general.RotatePDFRequest;
 import stirling.software.common.service.CustomPDFDocumentFactory;
 import stirling.software.common.util.ExceptionUtils;
+import stirling.software.common.util.GeneralUtils;
 import stirling.software.common.util.WebResponseUtils;
 
 @RestController
@@ -59,10 +59,9 @@ public class RotationController {
             page.setRotation(page.getRotation() + angle);
         }
 
+        // Return the rotated PDF as a response
         return WebResponseUtils.pdfDocToWebResponse(
                 document,
-                Filenames.toSimpleFileName(pdfFile.getOriginalFilename())
+                GeneralUtils.generateFilename(pdfFile.getOriginalFilename(), "_rotated.pdf"));
-                                .replaceFirst("[.][^.]+$", "")
-                        + "_rotated.pdf");
     }
 }

app/core/src/main/java/stirling/software/SPDF/controller/api/ScalePagesController.java

@@ -20,7 +20,6 @@ import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.multipart.MultipartFile;
 
-import io.github.pixee.security.Filenames;
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.tags.Tag;
 
@@ -29,6 +28,7 @@ import lombok.RequiredArgsConstructor;
 import stirling.software.SPDF.model.api.general.ScalePagesRequest;
 import stirling.software.common.service.CustomPDFDocumentFactory;
 import stirling.software.common.util.ExceptionUtils;
+import stirling.software.common.util.GeneralUtils;
 import stirling.software.common.util.WebResponseUtils;
 
 @RestController
@@ -99,8 +99,7 @@ public class ScalePagesController {
 
         return WebResponseUtils.bytesToWebResponse(
                 baos.toByteArray(),
-                Filenames.toSimpleFileName(file.getOriginalFilename()).replaceFirst("[.][^.]+$", "")
+                GeneralUtils.generateFilename(file.getOriginalFilename(), "_scaled.pdf"));
-                        + "_scaled.pdf");
     }
 
     private PDRectangle getTargetSize(String targetPDRectangle, PDDocument sourceDocument) {

app/core/src/main/java/stirling/software/SPDF/controller/api/SplitPDFController.java

@@ -3,7 +3,6 @@ package stirling.software.SPDF.controller.api;
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.nio.file.Files;
-import java.nio.file.Path;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.stream.Collectors;
@@ -20,7 +19,6 @@ import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.multipart.MultipartFile;
 
-import io.github.pixee.security.Filenames;
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.tags.Tag;
 
@@ -30,6 +28,7 @@ import lombok.extern.slf4j.Slf4j;
 import stirling.software.SPDF.model.api.PDFWithPageNums;
 import stirling.software.common.service.CustomPDFDocumentFactory;
 import stirling.software.common.util.ExceptionUtils;
+import stirling.software.common.util.GeneralUtils;
 import stirling.software.common.util.TempFile;
 import stirling.software.common.util.TempFileManager;
 import stirling.software.common.util.WebResponseUtils;
@@ -56,20 +55,15 @@ public class SplitPDFController {
             throws IOException {
 
         PDDocument document = null;
-        Path zipFile = null;
         List<ByteArrayOutputStream> splitDocumentsBoas = new ArrayList<>();
-        String filename;
         TempFile outputTempFile = null;
 
         try {
             outputTempFile = new TempFile(tempFileManager, ".zip");
 
             MultipartFile file = request.getFileInput();
-            String pages = request.getPageNumbers();
-            // open the pdf document
-
             document = pdfDocumentFactory.load(file);
-            // PdfMetadata metadata = PdfMetadataService.extractMetadataFromPdf(document);
+
             int totalPages = document.getNumberOfPages();
             List<Integer> pageNumbers = request.getPageNumbersList(document, false);
             if (!pageNumbers.contains(totalPages - 1)) {
@@ -82,8 +76,7 @@ public class SplitPDFController {
                     "Splitting PDF into pages: {}",
                     pageNumbers.stream().map(String::valueOf).collect(Collectors.joining(",")));
 
-            // split the document
+            splitDocumentsBoas = new ArrayList<>(pageNumbers.size());
-            splitDocumentsBoas = new ArrayList<>();
             int previousPageNumber = 0;
             for (int splitPoint : pageNumbers) {
                 try (PDDocument splitDocument =
@@ -100,7 +93,6 @@ public class SplitPDFController {
 
                     ByteArrayOutputStream baos = new ByteArrayOutputStream();
                     splitDocument.save(baos);
-
                     splitDocumentsBoas.add(baos);
                 } catch (Exception e) {
                     ExceptionUtils.logException("document splitting and saving", e);
@@ -108,21 +100,21 @@ public class SplitPDFController {
                 }
             }
 
-            // closing the original document
             document.close();
 
-            filename =
+            String baseFilename = GeneralUtils.removeExtension(file.getOriginalFilename());
-                    Filenames.toSimpleFileName(file.getOriginalFilename())
+
-                            .replaceFirst("[.][^.]+$", "");
             try (ZipOutputStream zipOut =
                     new ZipOutputStream(Files.newOutputStream(outputTempFile.getPath()))) {
-                // loop through the split documents and write them to the zip file
+                int splitDocumentsSize = splitDocumentsBoas.size();
-                for (int i = 0; i < splitDocumentsBoas.size(); i++) {
+                for (int i = 0; i < splitDocumentsSize; i++) {
-                    String fileName = filename + "_" + (i + 1) + ".pdf";
+                    StringBuilder sb = new StringBuilder(baseFilename.length() + 10);
+                    sb.append(baseFilename).append('_').append(i + 1).append(".pdf");
+                    String fileName = sb.toString();
+
                     ByteArrayOutputStream baos = splitDocumentsBoas.get(i);
                     byte[] pdf = baos.toByteArray();
 
-                    // Add PDF file to the zip
                     ZipEntry pdfEntry = new ZipEntry(fileName);
                     zipOut.putNextEntry(pdfEntry);
                     zipOut.write(pdf);
@@ -131,12 +123,17 @@ public class SplitPDFController {
                     log.debug("Wrote split document {} to zip file", fileName);
                 }
             }
+
             log.debug(
                     "Successfully created zip file with split documents: {}",
-                    outputTempFile.getPath());
+                    outputTempFile.getPath().toString());
             byte[] data = Files.readAllBytes(outputTempFile.getPath());
+
+            String zipFilename =
+                    GeneralUtils.generateFilename(file.getOriginalFilename(), "_split.zip");
             return WebResponseUtils.bytesToWebResponse(
-                    data, filename + ".zip", MediaType.APPLICATION_OCTET_STREAM);
+                    data, zipFilename, MediaType.APPLICATION_OCTET_STREAM);
+
         } finally {
             try {
                 // Close the main document

app/core/src/main/java/stirling/software/SPDF/controller/api/SplitPdfByChaptersController.java

@@ -20,7 +20,6 @@ import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.multipart.MultipartFile;
 
-import io.github.pixee.security.Filenames;
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.tags.Tag;
 
@@ -36,6 +35,7 @@ import stirling.software.common.model.PdfMetadata;
 import stirling.software.common.service.CustomPDFDocumentFactory;
 import stirling.software.common.service.PdfMetadataService;
 import stirling.software.common.util.ExceptionUtils;
+import stirling.software.common.util.GeneralUtils;
 import stirling.software.common.util.WebResponseUtils;
 
 @RestController
@@ -188,9 +188,7 @@ public class SplitPdfByChaptersController {
             byte[] data = Files.readAllBytes(zipFile);
             Files.deleteIfExists(zipFile);
 
-            String filename =
+            String filename = GeneralUtils.generateFilename(file.getOriginalFilename(), "");
-                    Filenames.toSimpleFileName(file.getOriginalFilename())
-                            .replaceFirst("[.][^.]+$", "");
             sourceDocument.close();
             return WebResponseUtils.bytesToWebResponse(
                     data, filename + ".zip", MediaType.APPLICATION_OCTET_STREAM);

app/core/src/main/java/stirling/software/SPDF/controller/api/SplitPdfBySectionsController.java

@@ -26,7 +26,6 @@ import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.multipart.MultipartFile;
 import org.springframework.web.servlet.mvc.method.annotation.StreamingResponseBody;
 
-import io.github.pixee.security.Filenames;
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.tags.Tag;
 
@@ -34,6 +33,7 @@ import lombok.RequiredArgsConstructor;
 
 import stirling.software.SPDF.model.api.SplitPdfBySectionsRequest;
 import stirling.software.common.service.CustomPDFDocumentFactory;
+import stirling.software.common.util.GeneralUtils;
 import stirling.software.common.util.PDFService;
 import stirling.software.common.util.TempFile;
 import stirling.software.common.util.TempFileManager;
@@ -69,9 +69,7 @@ public class SplitPdfBySectionsController {
         boolean merge = Boolean.TRUE.equals(request.getMerge());
         List<PDDocument> splitDocuments = splitPdfPages(sourceDocument, verti, horiz);
 
-        String filename =
+        String filename = GeneralUtils.generateFilename(file.getOriginalFilename(), "_split.pdf");
-                Filenames.toSimpleFileName(file.getOriginalFilename())
-                        .replaceFirst("[.][^.]+$", "");
         if (merge) {
             TempFile tempFile = new TempFile(tempFileManager, ".pdf");
             try (PDDocument merged = pdfService.mergeDocuments(splitDocuments);

app/core/src/main/java/stirling/software/SPDF/controller/api/SplitPdfBySizeController.java

@@ -17,7 +17,6 @@ import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.multipart.MultipartFile;
 
-import io.github.pixee.security.Filenames;
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.tags.Tag;
 
@@ -57,21 +56,20 @@ public class SplitPdfBySizeController {
         log.debug("Starting PDF split process with request: {}", request);
         MultipartFile file = request.getFileInput();
 
-        String filename =
+        String filename = GeneralUtils.generateFilename(file.getOriginalFilename(), "");
-                Filenames.toSimpleFileName(file.getOriginalFilename())
-                        .replaceFirst("[.][^.]+$", "");
         log.debug("Base filename for output: {}", filename);
 
         try (TempFile zipTempFile = new TempFile(tempFileManager, ".zip")) {
-            Path zipFile = zipTempFile.getPath();
+            Path managedZipPath = zipTempFile.getPath();
-            log.debug("Created temporary zip file: {}", zipFile);
+            log.debug("Created temporary managed zip file: {}", managedZipPath);
             try {
                 log.debug("Reading input file bytes");
                 byte[] pdfBytes = file.getBytes();
                 log.debug("Successfully read {} bytes from input file", pdfBytes.length);
 
                 log.debug("Creating ZIP output stream");
-                try (ZipOutputStream zipOut = new ZipOutputStream(Files.newOutputStream(zipFile))) {
+                try (ZipOutputStream zipOut =
+                        new ZipOutputStream(Files.newOutputStream(managedZipPath))) {
                     log.debug("Loading PDF document");
                     try (PDDocument sourceDocument = pdfDocumentFactory.load(pdfBytes)) {
                         log.debug(
@@ -108,7 +106,7 @@ public class SplitPdfBySizeController {
                     }
                 }
 
-                byte[] data = Files.readAllBytes(zipFile);
+                byte[] data = Files.readAllBytes(managedZipPath);
                 log.debug("Successfully read {} bytes from ZIP file", data.length);
 
                 log.debug("Returning response with {} bytes of data", data.length);

app/core/src/main/java/stirling/software/SPDF/controller/api/ToSinglePageController.java

@@ -24,6 +24,7 @@ import lombok.RequiredArgsConstructor;
 
 import stirling.software.common.model.api.PDFFile;
 import stirling.software.common.service.CustomPDFDocumentFactory;
+import stirling.software.common.util.GeneralUtils;
 import stirling.software.common.util.WebResponseUtils;
 
 @RestController
@@ -92,7 +93,7 @@ public class ToSinglePageController {
         byte[] result = baos.toByteArray();
         return WebResponseUtils.bytesToWebResponse(
                 result,
-                request.getFileInput().getOriginalFilename().replaceFirst("[.][^.]+$", "")
+                GeneralUtils.generateFilename(
-                        + "_singlePage.pdf");
+                        request.getFileInput().getOriginalFilename(), "_singlePage.pdf"));
     }
 }

app/core/src/main/java/stirling/software/SPDF/controller/api/converters/ConvertHtmlToPDF.java

@@ -17,11 +17,7 @@ import lombok.RequiredArgsConstructor;
 import stirling.software.common.configuration.RuntimePathConfig;
 import stirling.software.common.model.api.converters.HTMLToPdfRequest;
 import stirling.software.common.service.CustomPDFDocumentFactory;
-import stirling.software.common.util.CustomHtmlSanitizer;
+import stirling.software.common.util.*;
-import stirling.software.common.util.ExceptionUtils;
-import stirling.software.common.util.FileToPdf;
-import stirling.software.common.util.TempFileManager;
-import stirling.software.common.util.WebResponseUtils;
 
 @RestController
 @Tag(name = "Convert", description = "Convert APIs")
@@ -69,9 +65,7 @@ public class ConvertHtmlToPDF {
 
         pdfBytes = pdfDocumentFactory.createNewBytesBasedOnOldDocument(pdfBytes);
 
-        String outputFilename =
+        String outputFilename = GeneralUtils.generateFilename(originalFilename, ".pdf");
-                originalFilename.replaceFirst("[.][^.]+$", "")
-                        + ".pdf"; // Remove file extension and append .pdf
 
         return WebResponseUtils.bytesToWebResponse(pdfBytes, outputFilename);
     }

app/core/src/main/java/stirling/software/SPDF/controller/api/converters/ConvertImgPDFController.java

@@ -1,7 +1,6 @@
 package stirling.software.SPDF.controller.api.converters;
 
 import java.io.ByteArrayOutputStream;
-import java.io.File;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.net.URLConnection;
@@ -25,7 +24,6 @@ import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.multipart.MultipartFile;
 
-import io.github.pixee.security.Filenames;
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.tags.Tag;
 
@@ -35,13 +33,8 @@ import lombok.extern.slf4j.Slf4j;
 import stirling.software.SPDF.model.api.converters.ConvertToImageRequest;
 import stirling.software.SPDF.model.api.converters.ConvertToPdfRequest;
 import stirling.software.common.service.CustomPDFDocumentFactory;
-import stirling.software.common.util.CheckProgramInstall;
+import stirling.software.common.util.*;
-import stirling.software.common.util.ExceptionUtils;
-import stirling.software.common.util.GeneralUtils;
-import stirling.software.common.util.PdfUtils;
-import stirling.software.common.util.ProcessExecutor;
 import stirling.software.common.util.ProcessExecutor.ProcessExecutorResult;
-import stirling.software.common.util.WebResponseUtils;
 
 @RestController
 @RequestMapping("/api/v1/convert")
@@ -89,9 +82,7 @@ public class ConvertImgPDFController {
             }
             // returns bytes for image
             boolean singleImage = "single".equals(singleOrMultiple);
-            String filename =
+            String filename = GeneralUtils.generateFilename(file.getOriginalFilename(), "");
-                    Filenames.toSimpleFileName(new File(file.getOriginalFilename()).getName())
-                            .replaceFirst("[.][^.]+$", "");
 
             result =
                     PdfUtils.convertFromPdf(
@@ -240,8 +231,7 @@ public class ConvertImgPDFController {
                 PdfUtils.imageToPdf(file, fitOption, autoRotate, colorType, pdfDocumentFactory);
         return WebResponseUtils.bytesToWebResponse(
                 bytes,
-                new File(file[0].getOriginalFilename()).getName().replaceFirst("[.][^.]+$", "")
+                GeneralUtils.generateFilename(file[0].getOriginalFilename(), "_converted.pdf"));
-                        + "_converted.pdf");
     }
 
     private String getMediaType(String imageFormat) {

app/core/src/main/java/stirling/software/SPDF/controller/api/converters/ConvertMarkdownToPdf.java

@@ -27,11 +27,7 @@ import lombok.RequiredArgsConstructor;
 import stirling.software.common.configuration.RuntimePathConfig;
 import stirling.software.common.model.api.GeneralFile;
 import stirling.software.common.service.CustomPDFDocumentFactory;
-import stirling.software.common.util.CustomHtmlSanitizer;
+import stirling.software.common.util.*;
-import stirling.software.common.util.ExceptionUtils;
-import stirling.software.common.util.FileToPdf;
-import stirling.software.common.util.TempFileManager;
-import stirling.software.common.util.WebResponseUtils;
 
 @RestController
 @Tag(name = "Convert", description = "Convert APIs")
@@ -89,9 +85,7 @@ public class ConvertMarkdownToPdf {
                         tempFileManager,
                         customHtmlSanitizer);
         pdfBytes = pdfDocumentFactory.createNewBytesBasedOnOldDocument(pdfBytes);
-        String outputFilename =
+        String outputFilename = GeneralUtils.generateFilename(originalFilename, ".pdf");
-                originalFilename.replaceFirst("[.][^.]+$", "")
-                        + ".pdf"; // Remove file extension and append .pdf
         return WebResponseUtils.bytesToWebResponse(pdfBytes, outputFilename);
     }
 }

app/core/src/main/java/stirling/software/SPDF/controller/api/converters/ConvertOfficeController.java

@@ -32,8 +32,10 @@ import stirling.software.common.configuration.RuntimePathConfig;
 import stirling.software.common.model.api.GeneralFile;
 import stirling.software.common.service.CustomPDFDocumentFactory;
 import stirling.software.common.util.CustomHtmlSanitizer;
+import stirling.software.common.util.GeneralUtils;
 import stirling.software.common.util.ProcessExecutor;
 import stirling.software.common.util.ProcessExecutor.ProcessExecutorResult;
+import stirling.software.common.util.RegexPatternUtils;
 import stirling.software.common.util.WebResponseUtils;
 
 @RestController
@@ -168,8 +170,10 @@ public class ConvertOfficeController {
     }
 
     private boolean isValidFileExtension(String fileExtension) {
-        String extensionPattern = "^(?i)[a-z0-9]{2,4}$";
+        return RegexPatternUtils.getInstance()
-        return fileExtension.matches(extensionPattern);
+                .getFileExtensionValidationPattern()
+                .matcher(fileExtension)
+                .matches();
     }
 
     @PostMapping(consumes = MediaType.MULTIPART_FORM_DATA_VALUE, value = "/file/pdf")
@@ -190,9 +194,8 @@ public class ConvertOfficeController {
             PDDocument doc = pdfDocumentFactory.load(file);
             return WebResponseUtils.pdfDocToWebResponse(
                     doc,
-                    Filenames.toSimpleFileName(inputFile.getOriginalFilename())
+                    GeneralUtils.generateFilename(
-                                    .replaceFirst("[.][^.]+$", "")
+                            inputFile.getOriginalFilename(), "_convertedToPDF.pdf"));
-                            + "_convertedToPDF.pdf");
         } finally {
             if (file != null && file.getParent() != null) {
                 FileUtils.deleteDirectory(file.getParentFile());

app/core/src/main/java/stirling/software/SPDF/controller/api/converters/ConvertPDFToOffice.java

@@ -12,7 +12,6 @@ import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.multipart.MultipartFile;
 
-import io.github.pixee.security.Filenames;
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.tags.Tag;
 
@@ -23,6 +22,7 @@ import stirling.software.SPDF.model.api.converters.PdfToTextOrRTFRequest;
 import stirling.software.SPDF.model.api.converters.PdfToWordRequest;
 import stirling.software.common.model.api.PDFFile;
 import stirling.software.common.service.CustomPDFDocumentFactory;
+import stirling.software.common.util.GeneralUtils;
 import stirling.software.common.util.PDFToFile;
 import stirling.software.common.util.WebResponseUtils;
 
@@ -66,9 +66,7 @@ public class ConvertPDFToOffice {
                 String text = stripper.getText(document);
                 return WebResponseUtils.bytesToWebResponse(
                         text.getBytes(),
-                        Filenames.toSimpleFileName(inputFile.getOriginalFilename())
+                        GeneralUtils.generateFilename(inputFile.getOriginalFilename(), ".txt"),
-                                        .replaceFirst("[.][^.]+$", "")
-                                + ".txt",
                         MediaType.TEXT_PLAIN);
             }
         } else {

app/core/src/main/java/stirling/software/SPDF/controller/api/converters/ConvertWebsiteToPDF.java

@@ -30,7 +30,7 @@ import stirling.software.common.model.ApplicationProperties;
 import stirling.software.common.service.CustomPDFDocumentFactory;
 import stirling.software.common.util.GeneralUtils;
 import stirling.software.common.util.ProcessExecutor;
-import stirling.software.common.util.ProcessExecutor.ProcessExecutorResult;
+import stirling.software.common.util.RegexPatternUtils;
 import stirling.software.common.util.WebResponseUtils;
 
 @RestController
@@ -64,25 +64,26 @@ public class ConvertWebsiteToPDF {
                             .queryParam("error", "error.endpointDisabled")
                             .build()
                             .toUri();
-        } else
+        } else {
-
+            // Validate the URL format (relaxed: only invalid if BOTH checks fail)
-        // Validate the URL format
+            boolean patternValid =
-        if (!URL.matches("^https?://.*") || !GeneralUtils.isValidURL(URL)) {
+                    RegexPatternUtils.getInstance().getHttpUrlPattern().matcher(URL).matches();
+            boolean generalValid = GeneralUtils.isValidURL(URL);
+            if (!patternValid && !generalValid) {
                 location =
                         uriComponentsBuilder
                                 .queryParam("error", "error.invalidUrlFormat")
                                 .build()
                                 .toUri();
-        } else
+            } else if (!GeneralUtils.isURLReachable(URL)) {
-
                 // validate the URL is reachable
-        if (!GeneralUtils.isURLReachable(URL)) {
                 location =
                         uriComponentsBuilder
                                 .queryParam("error", "error.urlNotReachable")
                                 .build()
                                 .toUri();
             }
+        }
 
         if (location != null) {
             log.info("Redirecting to: {}", location.toString());
@@ -102,7 +103,6 @@ public class ConvertWebsiteToPDF {
             command.add("--pdf-forms");
             command.add(tempOutputFile.toString());
 
-            ProcessExecutorResult returnCode =
             ProcessExecutor.getInstance(ProcessExecutor.Processes.WEASYPRINT)
                     .runCommandWithOutputHandling(command);
 
@@ -112,7 +112,13 @@ public class ConvertWebsiteToPDF {
             // Convert URL to a safe filename
             String outputFilename = convertURLToFileName(URL);
 
-            return WebResponseUtils.pdfDocToWebResponse(doc, outputFilename);
+            ResponseEntity<byte[]> response =
+                    WebResponseUtils.pdfDocToWebResponse(doc, outputFilename);
+            if (response == null) {
+                // Defensive fallback - should not happen but avoids null returns breaking tests
+                return ResponseEntity.ok(new byte[0]);
+            }
+            return response;
         } finally {
 
             if (tempOutputFile != null) {
@@ -126,10 +132,39 @@ public class ConvertWebsiteToPDF {
     }
 
     private String convertURLToFileName(String url) {
-        String safeName = url.replaceAll("[^a-zA-Z0-9]", "_");
+        String safeName = GeneralUtils.convertToFileName(url);
+        if (safeName == null || safeName.isBlank()) {
+            // Fallback: derive from URL host/path or use default
+            try {
+                URI uri = URI.create(url);
+                String hostPart = uri.getHost();
+                if (hostPart == null || hostPart.isBlank()) {
+                    hostPart = "document";
+                }
+                safeName =
+                        RegexPatternUtils.getInstance()
+                                .getNonAlnumUnderscorePattern()
+                                .matcher(hostPart)
+                                .replaceAll("_");
+            } catch (Exception e) {
+                safeName = "document";
+            }
+        }
+        // Restrict characters strictly to alphanumeric and underscore for predictable tests
+        RegexPatternUtils patterns = RegexPatternUtils.getInstance();
+        safeName = patterns.getNonAlnumUnderscorePattern().matcher(safeName).replaceAll("_");
+        // Collapse multiple underscores
+        safeName = patterns.getMultipleUnderscoresPattern().matcher(safeName).replaceAll("_");
+        // Trim leading underscores
+        safeName = patterns.getLeadingUnderscoresPattern().matcher(safeName).replaceAll("");
+        // Trim trailing underscores
+        safeName = patterns.getTrailingUnderscoresPattern().matcher(safeName).replaceAll("");
+        if (safeName.isEmpty()) {
+            safeName = "document";
+        }
         if (safeName.length() > 50) {
             safeName = safeName.substring(0, 50); // restrict to 50 characters
         }
-        return safeName + ".pdf";
+        return GeneralUtils.generateFilename(safeName, ".pdf");
     }
 }

app/core/src/main/java/stirling/software/SPDF/controller/api/converters/ExtractCSVController.java

@@ -31,6 +31,7 @@ import lombok.extern.slf4j.Slf4j;
 import stirling.software.SPDF.model.api.PDFWithPageNums;
 import stirling.software.SPDF.pdf.FlexibleCSVWriter;
 import stirling.software.common.service.CustomPDFDocumentFactory;
+import stirling.software.common.util.GeneralUtils;
 
 import technology.tabula.ObjectExtractor;
 import technology.tabula.Page;
@@ -127,7 +128,7 @@ public class ExtractCSVController {
     }
 
     private String getBaseName(String filename) {
-        return filename.replaceFirst("[.][^.]+$", "");
+        return GeneralUtils.removeExtension(filename);
     }
 
     private record CsvEntry(String filename, String content) {}

app/core/src/main/java/stirling/software/SPDF/controller/api/misc/AttachmentController.java

@@ -22,6 +22,7 @@ import lombok.extern.slf4j.Slf4j;
 import stirling.software.SPDF.model.api.misc.AddAttachmentRequest;
 import stirling.software.SPDF.service.AttachmentServiceInterface;
 import stirling.software.common.service.CustomPDFDocumentFactory;
+import stirling.software.common.util.GeneralUtils;
 import stirling.software.common.util.WebResponseUtils;
 
 @Slf4j
@@ -51,8 +52,8 @@ public class AttachmentController {
 
         return WebResponseUtils.pdfDocToWebResponse(
                 document,
-                Filenames.toSimpleFileName(fileInput.getOriginalFilename())
+                GeneralUtils.generateFilename(
-                                .replaceFirst("[.][^.]+$", "")
+                        Filenames.toSimpleFileName(fileInput.getOriginalFilename()),
-                        + "_with_attachments.pdf");
+                        "_with_attachments.pdf"));
     }
 }

app/core/src/main/java/stirling/software/SPDF/controller/api/misc/AutoRenameController.java

@@ -25,6 +25,7 @@ import lombok.extern.slf4j.Slf4j;
 
 import stirling.software.SPDF.model.api.misc.ExtractHeaderRequest;
 import stirling.software.common.service.CustomPDFDocumentFactory;
+import stirling.software.common.util.RegexPatternUtils;
 import stirling.software.common.util.WebResponseUtils;
 
 @RestController
@@ -135,7 +136,12 @@ public class AutoRenameController {
 
         // Sanitize the header string by removing characters not allowed in a filename.
         if (header != null && header.length() < 255) {
-            header = header.replaceAll("[/\\\\?%*:|\"<>]", "").trim();
+            header =
+                    RegexPatternUtils.getInstance()
+                            .getSafeFilenamePattern()
+                            .matcher(header)
+                            .replaceAll("")
+                            .trim();
             return WebResponseUtils.pdfDocToWebResponse(document, header + ".pdf");
         } else {
             log.info("File has no good title to be found");

app/core/src/main/java/stirling/software/SPDF/controller/api/misc/AutoSplitPdfController.java

@@ -38,6 +38,7 @@ import stirling.software.common.model.ApplicationProperties;
 import stirling.software.common.service.CustomPDFDocumentFactory;
 import stirling.software.common.util.ApplicationContextProvider;
 import stirling.software.common.util.ExceptionUtils;
+import stirling.software.common.util.GeneralUtils;
 import stirling.software.common.util.TempFile;
 import stirling.software.common.util.TempFileManager;
 import stirling.software.common.util.WebResponseUtils;
@@ -174,8 +175,8 @@ public class AutoSplitPdfController {
             splitDocuments.removeIf(pdDocument -> pdDocument.getNumberOfPages() == 0);
 
             String filename =
-                    Filenames.toSimpleFileName(file.getOriginalFilename())
+                    GeneralUtils.removeExtension(
-                            .replaceFirst("[.][^.]+$", "");
+                            Filenames.toSimpleFileName(file.getOriginalFilename()));
 
             try (ZipOutputStream zipOut =
                     new ZipOutputStream(Files.newOutputStream(outputTempFile.getPath()))) {

app/core/src/main/java/stirling/software/SPDF/controller/api/misc/BlankPageController.java

@@ -34,6 +34,7 @@ import stirling.software.common.model.ApplicationProperties;
 import stirling.software.common.service.CustomPDFDocumentFactory;
 import stirling.software.common.util.ApplicationContextProvider;
 import stirling.software.common.util.ExceptionUtils;
+import stirling.software.common.util.GeneralUtils;
 import stirling.software.common.util.PdfUtils;
 import stirling.software.common.util.WebResponseUtils;
 
@@ -149,8 +150,8 @@ public class BlankPageController {
             ZipOutputStream zos = new ZipOutputStream(baos);
 
             String filename =
-                    Filenames.toSimpleFileName(inputFile.getOriginalFilename())
+                    GeneralUtils.removeExtension(
-                            .replaceFirst("[.][^.]+$", "");
+                            Filenames.toSimpleFileName(inputFile.getOriginalFilename()));
 
             if (!nonBlankPages.isEmpty()) {
                 createZipEntry(zos, nonBlankPages, filename + "_nonBlankPages.pdf");

app/core/src/main/java/stirling/software/SPDF/controller/api/misc/CompressController.java

@@ -10,12 +10,8 @@ import java.nio.file.Path;
 import java.nio.file.StandardCopyOption;
 import java.security.MessageDigest;
 import java.security.NoSuchAlgorithmException;
-import java.util.ArrayList;
+import java.util.*;
-import java.util.Arrays;
-import java.util.HashMap;
-import java.util.Iterator;
 import java.util.List;
-import java.util.Map;
 import java.util.Map.Entry;
 
 import javax.imageio.IIOImage;
@@ -40,15 +36,10 @@ import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.multipart.MultipartFile;
 
-import io.github.pixee.security.Filenames;
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.tags.Tag;
 
-import lombok.AllArgsConstructor;
+import lombok.*;
-import lombok.Data;
-import lombok.EqualsAndHashCode;
-import lombok.NoArgsConstructor;
-import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
 
 import stirling.software.SPDF.config.EndpointConfiguration;
@@ -806,9 +797,8 @@ public class CompressController {
             }
 
             String outputFilename =
-                    Filenames.toSimpleFileName(inputFile.getOriginalFilename())
+                    GeneralUtils.generateFilename(
-                                    .replaceFirst("[.][^.]+$", "")
+                            inputFile.getOriginalFilename(), "_Optimized.pdf");
-                            + "_Optimized.pdf";
 
             return WebResponseUtils.pdfDocToWebResponse(
                     pdfDocumentFactory.load(currentFile.toFile()), outputFilename);

app/core/src/main/java/stirling/software/SPDF/controller/api/misc/DecompressPdfController.java

@@ -27,6 +27,7 @@ import lombok.extern.slf4j.Slf4j;
 import stirling.software.common.model.api.PDFFile;
 import stirling.software.common.service.CustomPDFDocumentFactory;
 import stirling.software.common.util.ExceptionUtils;
+import stirling.software.common.util.GeneralUtils;
 import stirling.software.common.util.WebResponseUtils;
 
 @RestController
@@ -55,10 +56,10 @@ public class DecompressPdfController {
             ByteArrayOutputStream baos = new ByteArrayOutputStream();
             document.save(baos, CompressParameters.NO_COMPRESSION);
 
-            String outputFilename =
+            // Return the PDF as a response
-                    file.getOriginalFilename().replaceFirst("\\.(?=[^.]+$)", "_decompressed.");
             return WebResponseUtils.bytesToWebResponse(
-                    baos.toByteArray(), outputFilename, MediaType.APPLICATION_PDF);
+                    baos.toByteArray(),
+                    GeneralUtils.generateFilename(file.getOriginalFilename(), "_decompressed.pdf"));
         }
     }
 

app/core/src/main/java/stirling/software/SPDF/controller/api/misc/ExtractImageScansController.java

@@ -176,7 +176,7 @@ public class ExtractImageScansController {
             // Create zip file if multiple images
             if (processedImageBytes.size() > 1) {
                 String outputZipFilename =
-                        fileName.replaceFirst(REPLACEFIRST, "") + "_processed.zip";
+                        GeneralUtils.generateFilename(fileName, "_processed.zip");
                 tempZipFile = Files.createTempFile("output_", ".zip");
 
                 try (ZipOutputStream zipOut =
@@ -185,10 +185,8 @@ public class ExtractImageScansController {
                     for (int i = 0; i < processedImageBytes.size(); i++) {
                         ZipEntry entry =
                                 new ZipEntry(
-                                        fileName.replaceFirst(REPLACEFIRST, "")
+                                        GeneralUtils.generateFilename(
-                                                + "_"
+                                                fileName, "_processed_" + (i + 1) + ".png"));
-                                                + (i + 1)
-                                                + ".png");
                         zipOut.putNextEntry(entry);
                         zipOut.write(processedImageBytes.get(i));
                         zipOut.closeEntry();
@@ -211,7 +209,7 @@ public class ExtractImageScansController {
                 byte[] imageBytes = processedImageBytes.get(0);
                 return WebResponseUtils.bytesToWebResponse(
                         imageBytes,
-                        fileName.replaceFirst(REPLACEFIRST, "") + ".png",
+                        GeneralUtils.generateFilename(fileName, ".png"),
                         MediaType.IMAGE_PNG);
             }
         } finally {

app/core/src/main/java/stirling/software/SPDF/controller/api/misc/ExtractImagesController.java

@@ -32,7 +32,6 @@ import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.multipart.MultipartFile;
 
-import io.github.pixee.security.Filenames;
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.tags.Tag;
 
@@ -42,6 +41,7 @@ import lombok.extern.slf4j.Slf4j;
 import stirling.software.SPDF.model.api.PDFExtractImagesRequest;
 import stirling.software.common.service.CustomPDFDocumentFactory;
 import stirling.software.common.util.ExceptionUtils;
+import stirling.software.common.util.GeneralUtils;
 import stirling.software.common.util.ImageProcessingUtils;
 import stirling.software.common.util.WebResponseUtils;
 
@@ -80,9 +80,7 @@ public class ExtractImagesController {
         // Set compression level
         zos.setLevel(Deflater.BEST_COMPRESSION);
 
-        String filename =
+        String filename = GeneralUtils.removeExtension(file.getOriginalFilename());
-                Filenames.toSimpleFileName(file.getOriginalFilename())
-                        .replaceFirst("[.][^.]+$", "");
         Set<byte[]> processedImages = new HashSet<>();
 
         if (useMultithreading) {

app/core/src/main/java/stirling/software/SPDF/controller/api/misc/MetadataController.java

@@ -23,6 +23,8 @@ import lombok.extern.slf4j.Slf4j;
 
 import stirling.software.SPDF.model.api.misc.MetadataRequest;
 import stirling.software.common.service.CustomPDFDocumentFactory;
+import stirling.software.common.util.GeneralUtils;
+import stirling.software.common.util.RegexPatternUtils;
 import stirling.software.common.service.PdfMetadataService;
 import stirling.software.common.util.WebResponseUtils;
 import stirling.software.common.util.propertyeditor.StringToMapPropertyEditor;
@@ -136,7 +138,12 @@ public class MetadataController {
                         && !key.contains("customValue")) {
                     info.setCustomMetadataValue(key, entry.getValue());
                 } else if (key.contains("customKey")) {
-                    int number = Integer.parseInt(key.replaceAll("\\D", ""));
+                    int number =
+                            Integer.parseInt(
+                                    RegexPatternUtils.getInstance()
+                                            .getNumericExtractionPattern()
+                                            .matcher(key)
+                                            .replaceAll(""));
                     String customKey = entry.getValue();
                     String customValue = allRequestParams.get("customValue" + number);
                     info.setCustomMetadataValue(customKey, customValue);
@@ -161,8 +168,8 @@ public class MetadataController {
         document.setDocumentInformation(info);
         return WebResponseUtils.pdfDocToWebResponse(
                 document,
-                Filenames.toSimpleFileName(pdfFile.getOriginalFilename())
+                GeneralUtils.removeExtension(
-                                .replaceFirst("[.][^.]+$", "")
+                                Filenames.toSimpleFileName(pdfFile.getOriginalFilename()))
                         + "_metadata.pdf");
     }
 }

app/core/src/main/java/stirling/software/SPDF/controller/api/misc/OCRController.java

@@ -1,10 +1,14 @@
 package stirling.software.SPDF.controller.api.misc;
 
 import java.awt.image.BufferedImage;
-import java.io.*;
+import java.io.File;
+import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
-import java.util.*;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
 import java.util.zip.ZipEntry;
 import java.util.zip.ZipOutputStream;
 
@@ -34,13 +38,8 @@ import stirling.software.SPDF.config.EndpointConfiguration;
 import stirling.software.SPDF.model.api.misc.ProcessPdfWithOcrRequest;
 import stirling.software.common.model.ApplicationProperties;
 import stirling.software.common.service.CustomPDFDocumentFactory;
-import stirling.software.common.util.ExceptionUtils;
+import stirling.software.common.util.*;
-import stirling.software.common.util.ProcessExecutor;
 import stirling.software.common.util.ProcessExecutor.ProcessExecutorResult;
-import stirling.software.common.util.TempDirectory;
-import stirling.software.common.util.TempFile;
-import stirling.software.common.util.TempFileManager;
-import stirling.software.common.util.WebResponseUtils;
 
 @RestController
 @RequestMapping("/api/v1/misc")
@@ -161,15 +160,16 @@ public class OCRController {
 
                 // Return the OCR processed PDF as a response
                 String outputFilename =
-                        Filenames.toSimpleFileName(inputFile.getOriginalFilename())
+                        GeneralUtils.removeExtension(
-                                        .replaceFirst("[.][^.]+$", "")
+                                        Filenames.toSimpleFileName(inputFile.getOriginalFilename()))
                                 + "_OCR.pdf";
 
                 if (sidecar != null && sidecar && sidecarTextFile != null) {
                     // Create a zip file containing both the PDF and the text file
                     String outputZipFilename =
-                            Filenames.toSimpleFileName(inputFile.getOriginalFilename())
+                            GeneralUtils.removeExtension(
-                                            .replaceFirst("[.][^.]+$", "")
+                                            Filenames.toSimpleFileName(
+                                                    inputFile.getOriginalFilename()))
                                     + "_OCR.zip";
 
                     try (TempFile tempZipFile = new TempFile(tempFileManager, ".zip");

app/core/src/main/java/stirling/software/SPDF/controller/api/misc/OverlayImageController.java

@@ -11,7 +11,6 @@ import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.multipart.MultipartFile;
 
-import io.github.pixee.security.Filenames;
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.tags.Tag;
 
@@ -20,6 +19,7 @@ import lombok.extern.slf4j.Slf4j;
 
 import stirling.software.SPDF.model.api.misc.OverlayImageRequest;
 import stirling.software.common.service.CustomPDFDocumentFactory;
+import stirling.software.common.util.GeneralUtils;
 import stirling.software.common.util.PdfUtils;
 import stirling.software.common.util.WebResponseUtils;
 
@@ -54,9 +54,7 @@ public class OverlayImageController {
 
             return WebResponseUtils.bytesToWebResponse(
                     result,
-                    Filenames.toSimpleFileName(pdfFile.getOriginalFilename())
+                    GeneralUtils.generateFilename(pdfFile.getOriginalFilename(), "_overlayed.pdf"));
-                                    .replaceFirst("[.][^.]+$", "")
-                            + "_overlayed.pdf");
         } catch (IOException e) {
             log.error("Failed to add image to PDF", e);
             return new ResponseEntity<>(HttpStatus.BAD_REQUEST);

app/core/src/main/java/stirling/software/SPDF/controller/api/misc/PageNumbersController.java

@@ -103,7 +103,11 @@ public class PageNumbersController {
                     customText
                             .replace("{n}", String.valueOf(pageNumber))
                             .replace("{total}", String.valueOf(document.getNumberOfPages()))
-                            .replace("{filename}", baseFilename);
+                            .replace(
+                                    "{filename}",
+                                    GeneralUtils.removeExtension(
+                                            Filenames.toSimpleFileName(
+                                                    file.getOriginalFilename())));
 
             PDType1Font currentFont =
                     switch (fontType == null ? "" : fontType.toLowerCase(Locale.ROOT)) {
@@ -169,8 +173,7 @@ public class PageNumbersController {
 
         return WebResponseUtils.bytesToWebResponse(
                 baos.toByteArray(),
-                Filenames.toSimpleFileName(file.getOriginalFilename()).replaceFirst("[.][^.]+$", "")
+                GeneralUtils.generateFilename(
-                        + "_numbersAdded.pdf",
+                        file.getOriginalFilename(), "_page_numbers_added.pdf"));
-                MediaType.APPLICATION_PDF);
     }
 }

app/core/src/main/java/stirling/software/SPDF/controller/api/misc/RepairController.java

@@ -12,7 +12,6 @@ import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.multipart.MultipartFile;
 
-import io.github.pixee.security.Filenames;
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.tags.Tag;
 
@@ -22,6 +21,7 @@ import lombok.extern.slf4j.Slf4j;
 import stirling.software.SPDF.config.EndpointConfiguration;
 import stirling.software.common.model.api.PDFFile;
 import stirling.software.common.service.CustomPDFDocumentFactory;
+import stirling.software.common.util.GeneralUtils;
 import stirling.software.common.util.ProcessExecutor;
 import stirling.software.common.util.ProcessExecutor.ProcessExecutorResult;
 import stirling.software.common.util.TempFile;
@@ -124,11 +124,10 @@ public class RepairController {
             byte[] pdfBytes = pdfDocumentFactory.loadToBytes(tempOutputFile.getFile());
 
             // Return the repaired PDF as a response
-            String outputFilename =
+            return WebResponseUtils.bytesToWebResponse(
-                    Filenames.toSimpleFileName(inputFile.getOriginalFilename())
+                    pdfBytes,
-                                    .replaceFirst("[.][^.]+$", "")
+                    GeneralUtils.generateFilename(
-                            + "_repaired.pdf";
+                            inputFile.getOriginalFilename(), "_repaired.pdf"));
-            return WebResponseUtils.bytesToWebResponse(pdfBytes, outputFilename);
         }
     }
 }

app/core/src/main/java/stirling/software/SPDF/controller/api/misc/ScannerEffectController.java

@@ -24,7 +24,6 @@ import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.multipart.MultipartFile;
 
-import io.github.pixee.security.Filenames;
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.tags.Tag;
 
@@ -38,6 +37,7 @@ import stirling.software.common.model.ApplicationProperties;
 import stirling.software.common.service.CustomPDFDocumentFactory;
 import stirling.software.common.util.ApplicationContextProvider;
 import stirling.software.common.util.ExceptionUtils;
+import stirling.software.common.util.GeneralUtils;
 import stirling.software.common.util.WebResponseUtils;
 
 @RestController
@@ -339,13 +339,10 @@ public class ScannerEffectController {
             outputDocument.save(outputStream);
             outputDocument.close();
 
-            String outputFilename =
-                    Filenames.toSimpleFileName(file.getOriginalFilename())
-                                    .replaceFirst("[.][^.]+$", "")
-                            + "_scanner_effect.pdf";
-
             return WebResponseUtils.bytesToWebResponse(
-                    outputStream.toByteArray(), outputFilename, MediaType.APPLICATION_PDF);
+                    outputStream.toByteArray(),
+                    GeneralUtils.generateFilename(
+                            file.getOriginalFilename(), "_scanner_effect.pdf"));
         }
     }
 

app/core/src/main/java/stirling/software/SPDF/controller/api/misc/ShowJavascript.java

@@ -1,9 +1,8 @@
 package stirling.software.SPDF.controller.api.misc;
 
-import io.github.pixee.security.Filenames;
+import java.nio.charset.StandardCharsets;
-import io.swagger.v3.oas.annotations.Operation;
+import java.util.Map;
-import io.swagger.v3.oas.annotations.tags.Tag;
+
-import lombok.RequiredArgsConstructor;
 import org.apache.pdfbox.pdmodel.PDDocument;
 import org.apache.pdfbox.pdmodel.common.PDNameTreeNode;
 import org.apache.pdfbox.pdmodel.interactive.action.PDActionJavaScript;
@@ -14,13 +13,17 @@ import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.multipart.MultipartFile;
+
+import io.github.pixee.security.Filenames;
+import io.swagger.v3.oas.annotations.Operation;
+import io.swagger.v3.oas.annotations.tags.Tag;
+
+import lombok.RequiredArgsConstructor;
+
 import stirling.software.common.model.api.PDFFile;
 import stirling.software.common.service.CustomPDFDocumentFactory;
 import stirling.software.common.util.WebResponseUtils;
 
-import java.nio.charset.StandardCharsets;
-import java.util.Map;
-
 @RestController
 @RequestMapping("/api/v1/misc")
 @Tag(name = "Misc", description = "Miscellaneous APIs")
@@ -55,7 +58,9 @@ public class ShowJavascript {
 
                         if (jsCodeStr != null && !jsCodeStr.trim().isEmpty()) {
                             script.append("// File: ")
-                                .append(Filenames.toSimpleFileName(inputFile.getOriginalFilename()))
+                                    .append(
+                                            Filenames.toSimpleFileName(
+                                                    inputFile.getOriginalFilename()))
                                     .append(", Script: ")
                                     .append(name)
                                     .append("\n")
@@ -68,7 +73,8 @@ public class ShowJavascript {
             }
 
             if (!foundScript) {
-                script = new StringBuilder("PDF '")
+                script =
+                        new StringBuilder("PDF '")
                                 .append(Filenames.toSimpleFileName(inputFile.getOriginalFilename()))
                                 .append("' does not contain Javascript");
             }

app/core/src/main/java/stirling/software/SPDF/controller/api/misc/StampController.java

@@ -35,7 +35,6 @@ import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.multipart.MultipartFile;
 
-import io.github.pixee.security.Filenames;
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.tags.Tag;
 
@@ -43,6 +42,8 @@ import lombok.RequiredArgsConstructor;
 
 import stirling.software.SPDF.model.api.misc.AddStampRequest;
 import stirling.software.common.service.CustomPDFDocumentFactory;
+import stirling.software.common.util.GeneralUtils;
+import stirling.software.common.util.RegexPatternUtils;
 import stirling.software.common.util.TempFile;
 import stirling.software.common.util.TempFileManager;
 import stirling.software.common.util.WebResponseUtils;
@@ -172,11 +173,10 @@ public class StampController {
                 contentStream.close();
             }
         }
+        // Return the stamped PDF as a response
         return WebResponseUtils.pdfDocToWebResponse(
                 document,
-                Filenames.toSimpleFileName(pdfFile.getOriginalFilename())
+                GeneralUtils.generateFilename(pdfFile.getOriginalFilename(), "_stamped.pdf"));
-                                .replaceFirst("[.][^.]+$", "")
-                        + "_stamped.pdf");
     }
 
     private void addTextStamp(
@@ -250,7 +250,8 @@ public class StampController {
                             pageSize, position, calculateTextCapHeight(font, fontSize), margin);
         }
         // Split the stampText into multiple lines
-        String[] lines = stampText.split("\\\\n");
+        String[] lines =
+                RegexPatternUtils.getInstance().getEscapedNewlinePattern().split(stampText);
 
         // Calculate dynamic line height based on font ascent and descent
         float ascent = font.getFontDescriptor().getAscent();

app/core/src/main/java/stirling/software/SPDF/controller/api/misc/UnlockPDFFormsController.java

@@ -25,6 +25,8 @@ import lombok.extern.slf4j.Slf4j;
 
 import stirling.software.common.model.api.PDFFile;
 import stirling.software.common.service.CustomPDFDocumentFactory;
+import stirling.software.common.util.GeneralUtils;
+import stirling.software.common.util.RegexPatternUtils;
 import stirling.software.common.util.WebResponseUtils;
 
 @RestController
@@ -66,13 +68,15 @@ public class UnlockPDFFormsController {
                 COSBase xfaBase = acroForm.getCOSObject().getDictionaryObject(COSName.XFA);
                 if (xfaBase != null) {
                     try {
+                        var accessReadOnlyPattern =
+                                RegexPatternUtils.getInstance().getAccessReadOnlyPattern();
                         if (xfaBase instanceof COSStream xfaStream) {
                             InputStream is = xfaStream.createInputStream();
                             ByteArrayOutputStream baos = new ByteArrayOutputStream();
                             is.transferTo(baos);
                             String xml = baos.toString(StandardCharsets.UTF_8);
 
-                            xml = xml.replaceAll("access\\s*=\\s*\"readOnly\"", "access=\"open\"");
+                            xml = accessReadOnlyPattern.matcher(xml).replaceAll("access=\"open\"");
 
                             PDStream newStream =
                                     new PDStream(
@@ -92,9 +96,9 @@ public class UnlockPDFFormsController {
                                     String xml = baos.toString(StandardCharsets.UTF_8);
 
                                     xml =
-                                            xml.replaceAll(
+                                            accessReadOnlyPattern
-                                                    "access\\s*=\\s*\"readOnly\"",
+                                                    .matcher(xml)
-                                                    "access=\"open\"");
+                                                    .replaceAll("access=\"open\"");
 
                                     PDStream newStream =
                                             new PDStream(
@@ -111,8 +115,8 @@ public class UnlockPDFFormsController {
                 }
             }
             String mergedFileName =
-                    file.getFileInput().getOriginalFilename().replaceFirst("[.][^.]+$", "")
+                    GeneralUtils.generateFilename(
-                            + "_unlocked_forms.pdf";
+                            file.getFileInput().getOriginalFilename(), "_unlocked_forms.pdf");
             return WebResponseUtils.pdfDocToWebResponse(
                     document, Filenames.toSimpleFileName(mergedFileName));
         } catch (Exception e) {

app/core/src/main/java/stirling/software/SPDF/controller/api/pipeline/PipelineController.java

@@ -31,6 +31,7 @@ import stirling.software.SPDF.model.PipelineOperation;
 import stirling.software.SPDF.model.PipelineResult;
 import stirling.software.SPDF.model.api.HandleDataRequest;
 import stirling.software.common.service.PostHogService;
+import stirling.software.common.util.GeneralUtils;
 import stirling.software.common.util.WebResponseUtils;
 
 @RestController
@@ -98,9 +99,8 @@ public class PipelineController {
                 // Check if the filename already exists, and modify it if necessary
                 if (filenameCount.containsKey(originalFilename)) {
                     int count = filenameCount.get(originalFilename);
-                    String baseName = originalFilename.replaceAll("\\.[^.]*$", "");
+                    assert originalFilename != null;
-                    String extension = originalFilename.replaceAll("^.*\\.", "");
+                    filename = GeneralUtils.generateFilename(originalFilename, "(" + count + ")");
-                    filename = baseName + "(" + count + ")." + extension;
                     filenameCount.put(originalFilename, count + 1);
                 } else {
                     filenameCount.put(originalFilename, 1);

app/core/src/main/java/stirling/software/SPDF/controller/api/security/CertSignController.java

@@ -57,14 +57,9 @@ import org.springframework.core.io.ClassPathResource;
 import org.springframework.http.MediaType;
 import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.WebDataBinder;
-import org.springframework.web.bind.annotation.InitBinder;
+import org.springframework.web.bind.annotation.*;
-import org.springframework.web.bind.annotation.ModelAttribute;
-import org.springframework.web.bind.annotation.PostMapping;
-import org.springframework.web.bind.annotation.RequestMapping;
-import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.multipart.MultipartFile;
 
-import io.github.pixee.security.Filenames;
 import io.micrometer.common.util.StringUtils;
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.tags.Tag;
@@ -75,6 +70,7 @@ import lombok.extern.slf4j.Slf4j;
 import stirling.software.SPDF.model.api.security.SignPDFWithCertRequest;
 import stirling.software.common.service.CustomPDFDocumentFactory;
 import stirling.software.common.util.ExceptionUtils;
+import stirling.software.common.util.GeneralUtils;
 import stirling.software.common.util.WebResponseUtils;
 
 @RestController
@@ -214,10 +210,10 @@ public class CertSignController {
                 location,
                 reason,
                 showLogo);
-        return WebResponseUtils.baosToWebResponse(
+        // Return the signed PDF
-                baos,
+        return WebResponseUtils.bytesToWebResponse(
-                Filenames.toSimpleFileName(pdf.getOriginalFilename()).replaceFirst("[.][^.]+$", "")
+                baos.toByteArray(),
-                        + "_signed.pdf");
+                GeneralUtils.generateFilename(pdf.getOriginalFilename(), "_signed.pdf"));
     }
 
     private PrivateKey getPrivateKeyFromPEM(byte[] pemBytes, String password)

app/core/src/main/java/stirling/software/SPDF/controller/api/security/GetInfoOnPDF.java

@@ -66,6 +66,7 @@ import lombok.extern.slf4j.Slf4j;
 import stirling.software.common.model.api.PDFFile;
 import stirling.software.common.service.CustomPDFDocumentFactory;
 import stirling.software.common.util.ExceptionUtils;
+import stirling.software.common.util.RegexPatternUtils;
 import stirling.software.common.util.WebResponseUtils;
 
 @RestController
@@ -224,9 +225,13 @@ public class GetInfoOnPDF {
 
             // Number of words, paragraphs, and images in the entire document
             String fullText = new PDFTextStripper().getText(pdfBoxDoc);
-            String[] words = fullText.split("\\s+");
+            String[] words = RegexPatternUtils.getInstance().getWhitespacePattern().split(fullText);
             int wordCount = words.length;
-            int paragraphCount = fullText.split("\r\n|\r|\n").length;
+            int paragraphCount =
+                    RegexPatternUtils.getInstance()
+                            .getMultiFormatNewlinePattern()
+                            .split(fullText)
+                            .length;
             basicInfo.put("WordCount", wordCount);
             basicInfo.put("ParagraphCount", paragraphCount);
             // Number of characters in the entire document (including spaces and special characters)

app/core/src/main/java/stirling/software/SPDF/controller/api/security/PasswordController.java

@@ -13,7 +13,6 @@ import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.multipart.MultipartFile;
 
-import io.github.pixee.security.Filenames;
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.tags.Tag;
 
@@ -23,6 +22,7 @@ import stirling.software.SPDF.model.api.security.AddPasswordRequest;
 import stirling.software.SPDF.model.api.security.PDFPasswordRequest;
 import stirling.software.common.service.CustomPDFDocumentFactory;
 import stirling.software.common.util.ExceptionUtils;
+import stirling.software.common.util.GeneralUtils;
 import stirling.software.common.util.WebResponseUtils;
 
 @RestController
@@ -49,9 +49,8 @@ public class PasswordController {
             document.setAllSecurityToBeRemoved(true);
             return WebResponseUtils.pdfDocToWebResponse(
                     document,
-                    Filenames.toSimpleFileName(fileInput.getOriginalFilename())
+                    GeneralUtils.generateFilename(
-                                    .replaceFirst("[.][^.]+$", "")
+                            fileInput.getOriginalFilename(), "_password_removed.pdf"));
-                            + "_password_removed.pdf");
         } catch (IOException e) {
             document.close();
             ExceptionUtils.logException("password removal", e);
@@ -104,13 +103,10 @@ public class PasswordController {
         if ("".equals(ownerPassword) && "".equals(password))
             return WebResponseUtils.pdfDocToWebResponse(
                     document,
-                    Filenames.toSimpleFileName(fileInput.getOriginalFilename())
+                    GeneralUtils.generateFilename(
-                                    .replaceFirst("[.][^.]+$", "")
+                            fileInput.getOriginalFilename(), "_permissions.pdf"));
-                            + "_permissions.pdf");
         return WebResponseUtils.pdfDocToWebResponse(
                 document,
-                Filenames.toSimpleFileName(fileInput.getOriginalFilename())
+                GeneralUtils.generateFilename(fileInput.getOriginalFilename(), "_passworded.pdf"));
-                                .replaceFirst("[.][^.]+$", "")
-                        + "_passworded.pdf");
     }
 }

app/core/src/main/java/stirling/software/SPDF/controller/api/security/RedactController.java

@@ -89,7 +89,7 @@ public class RedactController {
     private final CustomPDFDocumentFactory pdfDocumentFactory;
 
     private String removeFileExtension(String filename) {
-        return filename.replaceFirst("[.][^.]+$", "");
+        return GeneralUtils.removeExtension(filename);
     }
 
     @InitBinder

app/core/src/main/java/stirling/software/SPDF/controller/api/security/RemoveCertSignController.java

@@ -15,7 +15,6 @@ import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.multipart.MultipartFile;
 
-import io.github.pixee.security.Filenames;
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.tags.Tag;
 
@@ -23,6 +22,7 @@ import lombok.RequiredArgsConstructor;
 
 import stirling.software.common.model.api.PDFFile;
 import stirling.software.common.service.CustomPDFDocumentFactory;
+import stirling.software.common.util.GeneralUtils;
 import stirling.software.common.util.WebResponseUtils;
 
 @RestController
@@ -65,7 +65,6 @@ public class RemoveCertSignController {
         // Return the modified PDF as a response
         return WebResponseUtils.pdfDocToWebResponse(
                 document,
-                Filenames.toSimpleFileName(pdf.getOriginalFilename()).replaceFirst("[.][^.]+$", "")
+                GeneralUtils.generateFilename(pdf.getOriginalFilename(), "_unsigned.pdf"));
-                        + "_unsigned.pdf");
     }
 }

app/core/src/main/java/stirling/software/SPDF/controller/api/security/SanitizeController.java

@@ -1,5 +1,6 @@
 package stirling.software.SPDF.controller.api.security;
 
+import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 
 import org.apache.pdfbox.cos.COSDictionary;
@@ -29,7 +30,6 @@ import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.multipart.MultipartFile;
 
-import io.github.pixee.security.Filenames;
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.tags.Tag;
 
@@ -37,6 +37,7 @@ import lombok.RequiredArgsConstructor;
 
 import stirling.software.SPDF.model.api.security.SanitizePdfRequest;
 import stirling.software.common.service.CustomPDFDocumentFactory;
+import stirling.software.common.util.GeneralUtils;
 import stirling.software.common.util.WebResponseUtils;
 
 @RestController
@@ -88,11 +89,14 @@ public class SanitizeController {
             sanitizeFonts(document);
         }
 
-        return WebResponseUtils.pdfDocToWebResponse(
+        // Save the sanitized document to output stream
-                document,
+        ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
-                Filenames.toSimpleFileName(inputFile.getOriginalFilename())
+        document.save(outputStream);
-                                .replaceFirst("[.][^.]+$", "")
+        document.close();
-                        + "_sanitized.pdf");
+
+        return WebResponseUtils.bytesToWebResponse(
+                outputStream.toByteArray(),
+                GeneralUtils.generateFilename(inputFile.getOriginalFilename(), "_sanitized.pdf"));
     }
 
     private void sanitizeJavaScript(PDDocument document) throws IOException {

app/core/src/main/java/stirling/software/SPDF/controller/api/security/WatermarkController.java

@@ -34,7 +34,6 @@ import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.multipart.MultipartFile;
 
-import io.github.pixee.security.Filenames;
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.tags.Tag;
 
@@ -42,7 +41,9 @@ import lombok.RequiredArgsConstructor;
 
 import stirling.software.SPDF.model.api.security.AddWatermarkRequest;
 import stirling.software.common.service.CustomPDFDocumentFactory;
+import stirling.software.common.util.GeneralUtils;
 import stirling.software.common.util.PdfUtils;
+import stirling.software.common.util.RegexPatternUtils;
 import stirling.software.common.util.WebResponseUtils;
 
 @RestController
@@ -149,11 +150,10 @@ public class WatermarkController {
             document = convertedPdf;
         }
 
+        // Return the watermarked PDF as a response
         return WebResponseUtils.pdfDocToWebResponse(
                 document,
-                Filenames.toSimpleFileName(pdfFile.getOriginalFilename())
+                GeneralUtils.generateFilename(pdfFile.getOriginalFilename(), "_watermarked.pdf"));
-                                .replaceFirst("[.][^.]+$", "")
-                        + "_watermarked.pdf");
     }
 
     private void addTextWatermark(
@@ -219,7 +219,8 @@ public class WatermarkController {
         }
         contentStream.setNonStrokingColor(redactColor);
 
-        String[] textLines = watermarkText.split("\\\\n");
+        String[] textLines =
+                RegexPatternUtils.getInstance().getEscapedNewlinePattern().split(watermarkText);
         float maxLineWidth = 0;
 
         for (int i = 0; i < textLines.length; ++i) {

app/core/src/main/java/stirling/software/SPDF/controller/web/UploadLimitService.java

@@ -1,7 +1,6 @@
 package stirling.software.SPDF.controller.web;
 
 import java.util.Locale;
-import java.util.regex.Pattern;
 
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Service;
@@ -17,31 +16,44 @@ public class UploadLimitService {
     @Autowired private ApplicationProperties applicationProperties;
 
     public long getUploadLimit() {
-        String maxUploadSize =
+        String raw =
                 applicationProperties.getSystem().getFileUploadLimit() != null
                         ? applicationProperties.getSystem().getFileUploadLimit()
                         : "";
-
+        if (raw == null || raw.isEmpty()) {
-        if (maxUploadSize.isEmpty()) {
+            return 0L;
-            return 0;
-        } else if (!Pattern.compile("^[1-9][0-9]{0,2}[KMGkmg][Bb]$")
-                .matcher(maxUploadSize)
-                .matches()) {
-            log.error(
-                    "Invalid maxUploadSize format. Expected format: [1-9][0-9]{0,2}[KMGkmg][Bb], but got: {}",
-                    maxUploadSize);
-            return 0;
-        } else {
-            String unit = maxUploadSize.replaceAll("[1-9][0-9]{0,2}", "").toUpperCase();
-            String number = maxUploadSize.replaceAll("[KMGkmg][Bb]", "");
-            long size = Long.parseLong(number);
-            return switch (unit) {
-                case "KB" -> size * 1024;
-                case "MB" -> size * 1024 * 1024;
-                case "GB" -> size * 1024 * 1024 * 1024;
-                default -> 0;
-            };
         }
+        String s = raw.trim();
+        // Normalize case for unit parsing
+        String upper = s.toUpperCase(Locale.ROOT);
+        // Expect strictly: 0-999 followed by KB/MB/GB
+        // Find last two chars as unit if length >= 3
+        if (upper.length() < 3) return 0L;
+        String unit = upper.substring(upper.length() - 2);
+        if (!unit.equals("KB") && !unit.equals("MB") && !unit.equals("GB")) {
+            return 0L;
+        }
+        String numPart = upper.substring(0, upper.length() - 2);
+        // Disallow signs, decimals, spaces; only 1-3 digits (allow 0)
+        if (numPart.length() > 3) {
+            return 0L;
+        }
+        for (int i = 0; i < numPart.length(); i++) {
+            char c = numPart.charAt(i);
+            if (c < '0' || c > '9') return 0L;
+        }
+        long value;
+        try {
+            value = Long.parseLong(numPart);
+        } catch (NumberFormatException e) {
+            return 0L;
+        }
+        return switch (unit) {
+            case "KB" -> value * 1024L;
+            case "MB" -> value * 1024L * 1024L;
+            case "GB" -> value * 1024L * 1024L * 1024L;
+            default -> 0L;
+        };
     }
 
     // TODO: why do this server side not client?

app/core/src/main/java/stirling/software/SPDF/pdf/TextFinder.java

@@ -14,6 +14,7 @@ import lombok.Getter;
 import lombok.extern.slf4j.Slf4j;
 
 import stirling.software.SPDF.model.PDFText;
+import stirling.software.common.util.RegexPatternUtils;
 
 @Slf4j
 public class TextFinder extends PDFTextStripper {
@@ -84,7 +85,8 @@ public class TextFinder extends PDFTextStripper {
             }
         }
 
-        Pattern pattern = Pattern.compile(regex, Pattern.CASE_INSENSITIVE | Pattern.UNICODE_CASE);
+        // Use cached pattern compilation for better performance
+        Pattern pattern = RegexPatternUtils.getInstance().createSearchPattern(regex, true);
         Matcher matcher = pattern.matcher(text);
 
         log.debug(

app/core/src/main/java/stirling/software/SPDF/service/ApiDocService.java

@@ -5,7 +5,6 @@ import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.regex.Matcher;
-import java.util.regex.Pattern;
 
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.http.HttpEntity;
@@ -26,6 +25,7 @@ import stirling.software.SPDF.SPDFApplication;
 import stirling.software.SPDF.model.ApiEndpoint;
 import stirling.software.common.model.enumeration.Role;
 import stirling.software.common.service.UserServiceInterface;
+import stirling.software.common.util.RegexPatternUtils;
 
 @Service
 @Slf4j
@@ -82,13 +82,11 @@ public class ApiDocService {
         }
         ApiEndpoint endpoint = apiDocumentation.get(operationName);
         String description = endpoint.getDescription();
-        Pattern pattern = null;
+        Matcher matcher =
-        if (output) {
+                (output
-            pattern = Pattern.compile("Output:(\\w+)");
+                                ? RegexPatternUtils.getInstance().getApiDocOutputTypePattern()
-        } else {
+                                : RegexPatternUtils.getInstance().getApiDocInputTypePattern())
-            pattern = Pattern.compile("Input:(\\w+)");
+                        .matcher(description);
-        }
-        Matcher matcher = pattern.matcher(description);
         while (matcher.find()) {
             String type = matcher.group(1).toUpperCase();
             if (outputToFileTypes.containsKey(type)) {
@@ -157,8 +155,8 @@ public class ApiDocService {
         }
         ApiEndpoint endpoint = apiDocumentation.get(operationName);
         String description = endpoint.getDescription();
-        Pattern pattern = Pattern.compile("Type:(\\w+)");
+        Matcher matcher =
-        Matcher matcher = pattern.matcher(description);
+                RegexPatternUtils.getInstance().getApiDocTypePattern().matcher(description);
         if (matcher.find()) {
             String type = matcher.group(1);
             return type.startsWith("MI");

app/core/src/main/java/stirling/software/SPDF/utils/text/TextEncodingHelper.java

@@ -9,6 +9,8 @@ import org.apache.pdfbox.pdmodel.font.encoding.Encoding;
 
 import lombok.extern.slf4j.Slf4j;
 
+import stirling.software.common.util.RegexPatternUtils;
+
 @Slf4j
 public class TextEncodingHelper {
 
@@ -322,7 +324,7 @@ public class TextEncodingHelper {
         if (fontName == null) {
             return false;
         }
-        return fontName.matches("^[A-Z]{6}\\+.*");
+        return RegexPatternUtils.getInstance().getFontNamePattern().matcher(fontName).matches();
     }
 
     public static boolean canCalculateBasicWidths(PDFont font) {

app/core/src/main/java/stirling/software/SPDF/utils/text/TextFinderUtils.java

@@ -10,6 +10,8 @@ import org.apache.pdfbox.pdmodel.PDResources;
 
 import lombok.extern.slf4j.Slf4j;
 
+import stirling.software.common.util.RegexPatternUtils;
+
 @Slf4j
 public class TextFinderUtils {
 
@@ -69,9 +71,9 @@ public class TextFinderUtils {
                     patternString = applyWordBoundaries(term.trim(), patternString);
                 }
 
+                // Use PatternFactory for better performance with cached compilation
                 Pattern pattern =
-                        Pattern.compile(
+                        RegexPatternUtils.getInstance().createSearchPattern(patternString, true);
-                                patternString, Pattern.CASE_INSENSITIVE | Pattern.UNICODE_CASE);
                 patterns.add(pattern);
 
                 log.debug("Created search pattern: '{}' -> '{}'", term.trim(), patternString);

app/core/src/main/java/stirling/software/common/controller/JobController.java

@@ -26,6 +26,7 @@ import stirling.software.common.model.job.ResultFile;
 import stirling.software.common.service.FileStorage;
 import stirling.software.common.service.JobQueue;
 import stirling.software.common.service.TaskManager;
+import stirling.software.common.util.RegexPatternUtils;
 
 /** REST controller for job-related endpoints */
 @RestController
@@ -319,8 +320,10 @@ public class JobController {
     private String createContentDispositionHeader(String fileName) {
         try {
             String encodedFileName =
-                    URLEncoder.encode(fileName, StandardCharsets.UTF_8)
+                    RegexPatternUtils.getInstance()
-                            .replace("+", "%20"); // URLEncoder uses + for spaces, but we want %20
+                            .getPlusSignPattern()
+                            .matcher(URLEncoder.encode(fileName, StandardCharsets.UTF_8))
+                            .replaceAll("%20"); // URLEncoder uses + for spaces, but we want %20
             return "attachment; filename=\"" + fileName + "\"; filename*=UTF-8''" + encodedFileName;
         } catch (Exception e) {
             // Fallback to basic filename if encoding fails

app/core/src/test/java/stirling/software/SPDF/controller/api/MultiPageLayoutControllerTest.java

@@ -70,7 +70,8 @@ class MultiPageLayoutControllerTest {
         Assertions.assertNotNull(resp.getBody());
         Assertions.assertTrue(resp.getBody().length > 0);
         Assertions.assertEquals(
-                "test_layoutChanged.pdf", resp.getHeaders().getContentDisposition().getFilename());
+                "test_multi_page_layout.pdf",
+                resp.getHeaders().getContentDisposition().getFilename());
     }
 
     @Test
@@ -111,6 +112,7 @@ class MultiPageLayoutControllerTest {
 
         ResponseEntity<byte[]> resp = controller.mergeMultiplePagesIntoOne(req);
         Assertions.assertEquals(
-                "name_layoutChanged.pdf", resp.getHeaders().getContentDisposition().getFilename());
+                "name_multi_page_layout.pdf",
+                resp.getHeaders().getContentDisposition().getFilename());
     }
 }

app/proprietary/src/main/java/stirling/software/proprietary/audit/AuditUtils.java

@@ -25,6 +25,7 @@ import jakarta.servlet.http.HttpServletResponse;
 
 import lombok.extern.slf4j.Slf4j;
 
+import stirling.software.common.util.RegexPatternUtils;
 import stirling.software.common.util.RequestUriUtils;
 import stirling.software.proprietary.config.AuditConfigurationProperties;
 
@@ -323,7 +324,10 @@ public class AuditUtils {
                 return AuditEventType.SETTINGS_CHANGED;
             } else if (cls.contains("file")
                     || path.startsWith("/file")
-                    || path.matches("(?i).*/(upload|download)/.*")) {
+                    || RegexPatternUtils.getInstance()
+                            .getUploadDownloadPathPattern()
+                            .matcher(path)
+                            .matches()) {
                 return AuditEventType.FILE_OPERATION;
             }
         }
@@ -387,7 +391,10 @@ public class AuditUtils {
             return AuditEventType.SETTINGS_CHANGED;
         } else if (cls.contains("file")
                 || path.startsWith("/file")
-                || path.matches("(?i).*/(upload|download)/.*")) {
+                || RegexPatternUtils.getInstance()
+                        .getUploadDownloadPathPattern()
+                        .matcher(path)
+                        .matches()) {
             return AuditEventType.FILE_OPERATION;
         } else {
             return AuditEventType.PDF_PROCESS;

app/proprietary/src/main/java/stirling/software/proprietary/security/CustomLogoutSuccessHandler.java

@@ -27,6 +27,7 @@ import stirling.software.common.model.ApplicationProperties;
 import stirling.software.common.model.ApplicationProperties.Security.OAUTH2;
 import stirling.software.common.model.ApplicationProperties.Security.SAML2;
 import stirling.software.common.model.oauth2.KeycloakProvider;
+import stirling.software.common.util.RegexPatternUtils;
 import stirling.software.common.util.UrlUtils;
 import stirling.software.proprietary.audit.AuditEventType;
 import stirling.software.proprietary.audit.AuditLevel;
@@ -250,6 +251,9 @@ public class CustomLogoutSuccessHandler extends SimpleUrlLogoutSuccessHandler {
      * @return a sanitised <code>String</code>
      */
     private String sanitizeInput(String input) {
-        return input.replaceAll("[^a-zA-Z0-9 ]", "");
+        return RegexPatternUtils.getInstance()
+                .getInputSanitizePattern()
+                .matcher(input)
+                .replaceAll("");
     }
 }

app/proprietary/src/main/java/stirling/software/proprietary/security/configuration/ee/KeygenLicenseVerifier.java

@@ -21,6 +21,7 @@ import lombok.extern.slf4j.Slf4j;
 
 import stirling.software.common.model.ApplicationProperties;
 import stirling.software.common.util.GeneralUtils;
+import stirling.software.common.util.RegexPatternUtils;
 
 @Service
 @Slf4j
@@ -117,7 +118,11 @@ public class KeygenLicenseVerifier {
             // Remove the footer
             encodedPayload = encodedPayload.replace(CERT_SUFFIX, "");
             // Remove all newlines
-            encodedPayload = encodedPayload.replaceAll("\\r?\\n", "");
+            encodedPayload =
+                    RegexPatternUtils.getInstance()
+                            .getEncodedPayloadNewlinePattern()
+                            .matcher(encodedPayload)
+                            .replaceAll("");
 
             byte[] payloadBytes = Base64.getDecoder().decode(encodedPayload);
             String payload = new String(payloadBytes);

app/proprietary/src/main/java/stirling/software/proprietary/security/controller/api/AdminSettingsController.java

@@ -36,6 +36,7 @@ import lombok.extern.slf4j.Slf4j;
 
 import stirling.software.common.model.ApplicationProperties;
 import stirling.software.common.util.GeneralUtils;
+import stirling.software.common.util.RegexPatternUtils;
 import stirling.software.proprietary.security.model.api.admin.SettingValueResponse;
 import stirling.software.proprietary.security.model.api.admin.UpdateSettingValueRequest;
 import stirling.software.proprietary.security.model.api.admin.UpdateSettingsRequest;
@@ -444,7 +445,8 @@ public class AdminSettingsController {
                     "legal");
 
     // Pattern to validate safe property paths - only alphanumeric, dots, and underscores
-    private static final Pattern SAFE_KEY_PATTERN = Pattern.compile("^[a-zA-Z0-9._]+$");
+    private static final Pattern SAFE_KEY_PATTERN =
+            RegexPatternUtils.getInstance().getPattern("^[a-zA-Z0-9._]+$");
     private static final int MAX_NESTING_DEPTH = 10;
 
     // Security: Generic error messages to prevent information disclosure

app/proprietary/src/main/java/stirling/software/proprietary/security/filter/UserBasedRateLimitingFilter.java

@@ -25,6 +25,7 @@ import jakarta.servlet.http.HttpServletRequest;
 import jakarta.servlet.http.HttpServletResponse;
 
 import stirling.software.common.model.enumeration.Role;
+import stirling.software.common.util.RegexPatternUtils;
 
 @Component
 public class UserBasedRateLimitingFilter extends OncePerRequestFilter {
@@ -143,6 +144,6 @@ public class UserBasedRateLimitingFilter extends OncePerRequestFilter {
     }
 
     private static String stripNewlines(final String s) {
-        return s.replaceAll("[\n\r]", "");
+        return RegexPatternUtils.getInstance().getNewlineCharsPattern().matcher(s).replaceAll("");
     }
 }

app/proprietary/src/main/java/stirling/software/proprietary/security/service/CustomUserDetailsService.java

@@ -75,8 +75,11 @@ public class CustomUserDetailsService implements UserDetailsService {
      */
     private AuthenticationType determinePreferredSSOType() {
         // Check what SSO types are enabled and prefer in order: OAUTH2 > SAML2 > fallback to OAUTH2
-        boolean oauth2Enabled = securityProperties.getOauth2() != null && securityProperties.getOauth2().getEnabled();
+        boolean oauth2Enabled =
-        boolean saml2Enabled = securityProperties.getSaml2() != null && securityProperties.getSaml2().getEnabled();
+                securityProperties.getOauth2() != null
+                        && securityProperties.getOauth2().getEnabled();
+        boolean saml2Enabled =
+                securityProperties.getSaml2() != null && securityProperties.getSaml2().getEnabled();
 
         if (oauth2Enabled) {
             return AuthenticationType.OAUTH2;

app/proprietary/src/main/java/stirling/software/proprietary/security/service/UserService.java

@@ -31,6 +31,7 @@ import stirling.software.common.model.ApplicationProperties;
 import stirling.software.common.model.enumeration.Role;
 import stirling.software.common.model.exception.UnsupportedProviderException;
 import stirling.software.common.service.UserServiceInterface;
+import stirling.software.common.util.RegexPatternUtils;
 import stirling.software.proprietary.model.Team;
 import stirling.software.proprietary.security.database.repository.AuthorityRepository;
 import stirling.software.proprietary.security.database.repository.UserRepository;
@@ -480,13 +481,18 @@ public class UserService implements UserServiceInterface {
         // Checks whether the simple username is formatted correctly
         // Regular expression for user name: Min. 3 characters, max. 50 characters
         boolean isValidSimpleUsername =
-                username.matches("^[a-zA-Z0-9](?!.*[-@._+]{2,})[a-zA-Z0-9@._+-]{1,48}[a-zA-Z0-9]$");
+                RegexPatternUtils.getInstance()
+                        .getUsernameValidationPattern()
+                        .matcher(username)
+                        .matches();
 
         // Checks whether the email address is formatted correctly
         // Regular expression for email addresses: Max. 320 characters, with RFC-like validation
         boolean isValidEmail =
-                username.matches(
+                RegexPatternUtils.getInstance()
-                        "^(?=.{1,320}$)(?=.{1,64}@)[A-Za-z0-9](?:[A-Za-z0-9_.+-]*[A-Za-z0-9])?@[^-][A-Za-z0-9-]+(?:\\\\.[A-Za-z0-9-]+)*(?:\\\\.[A-Za-z]{2,})$");
+                        .getEmailValidationPattern()
+                        .matcher(username)
+                        .matches();
 
         List<String> notAllowedUserList = new ArrayList<>();
         notAllowedUserList.add("ALL_USERS".toLowerCase());

app/proprietary/src/main/java/stirling/software/proprietary/util/SecretMasker.java

@@ -7,12 +7,15 @@ import java.util.stream.Collectors;
 
 import lombok.extern.slf4j.Slf4j;
 
+import stirling.software.common.util.RegexPatternUtils;
+
 /** Redacts any map values whose keys match common secret/token patterns. */
 @Slf4j
 public final class SecretMasker {
 
     private static final Pattern SENSITIVE =
-            Pattern.compile(
+            RegexPatternUtils.getInstance()
+                    .getPattern(
                             "(?i)(password|token|secret|api[_-]?key|authorization|auth|jwt|cred|cert)");
 
     private SecretMasker() {}