import java.io.File;

import java.util.regex.Pattern;

class DirectorySanitizer {

/**

* Sanitizes a directory path to prevent malicious execution.

*

* @param input The directory path to sanitize.

* @return A sanitized directory path, or null if the input is invalid.

*/

public static String sanitizeDirectory(String input) {

if (input == null || input.trim().isEmpty()) {

return null; // Handle null or empty input

}

// Basic validation: Check for dangerous characters and path traversal attempts.

String sanitizedPath = input.replaceAll("[<>\\\"/\\?*]", ""); // Remove potentially harmful characters

sanitizedPath = sanitizedPath.replace("..", ""); // Remove path traversal sequences

// Validate the sanitized path to ensure it's a valid directory.

File file = new File(sanitizedPath);

if (!file.exists() || !file.isDirectory()) {

return null; // Invalid directory

}

return sanitizedPath;

}

public static void main(String[] args) {

// Example usage

String input1 = "/path/to/my/directory";

String sanitized1 = sanitizeDirectory(input1);

System.out.println("Input: " + input1 + ", Sanitized: " + sanitized1); // Expected: /path/to/my/directory

String input2 = "c:\\path\\to\\my\\directory";

String sanitized2 = sanitizeDirectory(input2);

System.out.println("Input: " + input2 + ", Sanitized: " + sanitized2); // Expected: c:\path\to\my\directory

String input3 = "path/to/../another/directory";

String sanitized3 = sanitizeDirectory(input3);

System.out.println("Input: " + input3 + ", Sanitized: " + sanitized3); // Expected: path/to/another/directory

String input4 = "invalid/path";

String sanitized4 = sanitizeDirectory(input4);

System.out.println("Input: " + input4 + ", Sanitized: " + sanitized4); // Expected: null

String input5 = null;

String sanitized5 = sanitizeDirectory(input5);

System.out.println("Input: " + input5 + ", Sanitized: " + sanitized5); // Expected: null

String input6 = "";

String sanitized6 = sanitizeDirectory(input6);

System.out.println("Input: " + input6 + ", Sanitized: " + sanitized6); // Expected: null

}

}