DES加密解密算法java

DES加密解密算法是一种对称加密算法，在Java中可以使用JDK自带的Cipher类实现。下面是一个简单的示例代码：

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;
import java.util.Base64;

public class DesDemo {

    private static final String KEY_ALGORITHM = "DES";
    private static final String CIPHER_ALGORITHM = "DES/ECB/PKCS5Padding";

    public static String encrypt(String content, String password) throws Exception {
        SecretKey secretKey = generateKey(password);
        Cipher cipher = Cipher.getInstance(CIPHER_ALGORITHM);
        cipher.init(Cipher.ENCRYPT_MODE, secretKey);
        byte[] encryptedBytes = cipher.doFinal(content.getBytes(StandardCharsets.UTF_8));
        return Base64.getEncoder().encodeToString(encryptedBytes);
    }

    public static String decrypt(String content, String password) throws Exception {
        SecretKey secretKey = generateKey(password);
        Cipher cipher = Cipher.getInstance(CIPHER_ALGORITHM);
        cipher.init(Cipher.DECRYPT_MODE, secretKey);
        byte[] encryptedBytes = Base64.getDecoder().decode(content);
        byte[] decryptedBytes = cipher.doFinal(encryptedBytes);
        return new String(decryptedBytes, StandardCharsets.UTF_8);
    }

    private static SecretKey generateKey(String password) throws NoSuchAlgorithmException {
        KeyGenerator keyGenerator = KeyGenerator.getInstance(KEY_ALGORITHM);
        keyGenerator.init(56);
        return new SecretKeySpec(password.getBytes(StandardCharsets.UTF_8), KEY_ALGORITHM);
    }

    public static void main(String[] args) throws Exception {
        String content = "Hello, World!";
        String password = "12345678";
        String encryptedContent = encrypt(content, password);
        String decryptedContent = decrypt(encryptedContent, password);
        System.out.println("明文：" + content);
        System.out.println("密文：" + encryptedContent);
        System.out.println("解密后：" + decryptedContent);
    }
}