Java：如何在上传和下载文件时在文件名中包含特殊字符？

import java.io.UnsupportedEncodingException;
import java.net.URLDecoder;
import java.net.URLEncoder;

public class FileUtil {
    public static String encodeFileName(String fileName) {
        try {
            return URLEncoder.encode(fileName, "UTF-8");
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
            return fileName;
        }
    }

    public static String decodeFileName(String fileName) {
        try {
            return URLDecoder.decode(fileName, "UTF-8");
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
            return fileName;
        }
    }
}

String originalFileName = "特殊字符.txt";
String encodedFileName = FileUtil.encodeFileName(originalFileName);
System.out.println("Encoded file name: " + encodedFileName);

String decodedFileName = FileUtil.decodeFileName(encodedFileName);
System.out.println("Decoded file name: " + decodedFileName);

Encoded file name: %E7%89%B9%E6%AE%8A%E5%AD%97%E7%AC%A6.txt
Decoded file name: 特殊字符.txt