拆分java中的字符串而不删除匹配项

import java.util.ArrayList;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class SplitStringKeepDelimiter {
    public static void main(String[] args) {
        String input = "Java,Python,C++,JavaScript";
        String delimiter = ",";

        List<String> result = splitKeepDelimiter(input, delimiter);
        for (String s : result) {
            System.out.println("[" + s + "]");
        }
    }

    public static List<String> splitKeepDelimiter(String input, String delimiter) {
        List<String> result = new ArrayList<>();
        Pattern pattern = Pattern.compile("([^" + delimiter + "]*)(" + delimiter + ")");
        Matcher matcher = pattern.matcher(input);

        while (matcher.find()) {
            result.add(matcher.group(1)); // 添加分隔符前的部分
            result.add(matcher.group(2)); // 添加分隔符本身
        }

        // 处理最后一个元素（没有跟随分隔符）
        if (!input.endsWith(delimiter)) {
            result.add(matcher.group(1));
        }

        return result;
    }
}