java实现des加密

以下是Java实现DES加密的示例代码：

import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;

public class DES {
    private static final String ALGORITHM = "DES";

    public static byte[] encrypt(byte[] key, byte[] data) throws Exception {
        DESKeySpec desKeySpec = new DESKeySpec(key);
        SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(ALGORITHM);
        SecretKey secretKey = keyFactory.generateSecret(desKeySpec);

        Cipher cipher = Cipher.getInstance(ALGORITHM);
        cipher.init(Cipher.ENCRYPT_MODE, secretKey);

        return cipher.doFinal(data);
    }

    public static byte[] decrypt(byte[] key, byte[] data) throws Exception {
        DESKeySpec desKeySpec = new DESKeySpec(key);
        SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(ALGORITHM);
        SecretKey secretKey = keyFactory.generateSecret(desKeySpec);

        Cipher cipher = Cipher.getInstance(ALGORITHM);
        cipher.init(Cipher.DECRYPT_MODE, secretKey);

        return cipher.doFinal(data);
    }
}

使用示例：

public static void main(String[] args) throws Exception {
    byte[] key = "12345678".getBytes();
    byte[] data = "hello world".getBytes();

    byte[] encryptedData = DES.encrypt(key, data);
    byte[] decryptedData = DES.decrypt(key, encryptedData);

    System.out.println("Original data: " + new String(data));
    System.out.println("Encrypted data: " + new String(encryptedData));
    System.out.println("Decrypted data: " + new String(decryptedData));
}