import java.util.ArrayList;

import java.util.List;

import java.util.regex.Matcher;

import java.util.regex.Pattern;

public class UrlDecoder {

/**

* Decodes a list of URLs from a string, supporting older versions of Java.

*

* @param urlListString A string containing a list of URLs, separated by commas or semicolons.

* @return A list of decoded URLs. Returns an empty list if the input is null or empty.

*/

public static List<String> decodeUrls(String urlListString) {

List<String> urls = new ArrayList<>();

if (urlListString == null || urlListString.isEmpty()) {

return urls;

}

// Split the string by commas or semicolons

String[] urlStrings = urlListString.split("[,;]");

for (String urlString : urlStrings) {

// Trim whitespace

String trimmedUrl = urlString.trim();

if (!trimmedUrl.isEmpty()) {

// Basic URL validation (can be expanded)

if (trimmedUrl.startsWith("http://") || trimmedUrl.startsWith("https://")) {

urls.add(trimmedUrl);

} else {

//Handle relative URLs or other formats as needed. Add logic for more complex scenarios.

urls.add(trimmedUrl);

}

}

}

return urls;

}

public static void main(String[] args) {

//Example Usage

String urlList = "http://example.com,https://google.com;ftp://oldserver.com";

List<String> decodedUrls = decodeUrls(urlList);

for (String url : decodedUrls) {

System.out.println(url);

}

String emptyList = "";

List<String> emptyResult = decodeUrls(emptyList);

System.out.println("Empty List Result: " + emptyResult);

String nullList = null;

List<String> nullResult = decodeUrls(nullList);

System.out.println("Null List Result: " + nullResult);

}

}