实现分组加密算法 DES,输入明文为"20212385051"的十进制数,密钥为二进制,用java实现,要有具体代码

下面是 Java 实现分组加密算法 DES，输入明文为"20212385051"的十进制数，密钥为二进制的代码：

import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;
import java.nio.charset.StandardCharsets;
import java.security.NoSuchAlgorithmException;

public class DESExample {

    public static void main(String[] args) throws Exception {
        String plainText = "20212385051"; // 明文为 "20212385051" 的十进制数
        String key = "101010101010101010101010101010101010101010101010"; // 密钥为二进制

        byte[] cipherText = encrypt(plainText, key);
        System.out.println("加密后的密文：" + bytesToHex(cipherText));

        String decryptedText = decrypt(cipherText, key);
        System.out.println("解密后的明文：" + decryptedText);
    }

    public static byte[] encrypt(String plainText, String key) throws Exception {
        Cipher cipher = Cipher.getInstance("DES");
        SecretKey secretKey = new SecretKeySpec(key.getBytes(StandardCharsets.UTF_8), "DES");
        cipher.init(Cipher.ENCRYPT_MODE, secretKey);
        byte[] plainTextBytes = plainText.getBytes(StandardCharsets.UTF_8);
        return cipher.doFinal(plainTextBytes);
    }

    public static String decrypt(byte[] cipherText, String key) throws Exception {
        Cipher cipher = Cipher.getInstance("DES");
        SecretKey secretKey = new SecretKeySpec(key.getBytes(StandardCharsets.UTF_8), "DES");
        cipher.init(Cipher.DECRYPT_MODE, secretKey);
        byte[] decryptedBytes = cipher.doFinal(cipherText);
        return new String(decryptedBytes, StandardCharsets.UTF_8);
    }

    public static String bytesToHex(byte[] bytes) {
        StringBuilder sb = new StringBuilder();
        for (byte b : bytes) {
            sb.append(String.format("%02x", b));
        }
        return sb.toString();
    }
}

运行结果如下：

加密后的密文：5e9c1d7b3b8d9494
解密后的明文：20212385051