java DES加密解密

public class DESUtil {

private final static String DES = "DES";

public static void main(String[] args) throws Exception {

String data = "123 456";

String key = "wang!@#$%";

System.err.println(encrypt(data, key));

System.err.println(decrypt(encrypt(data, key), key));

}

/**

* Description 根据键值进行加密

* @param data

* @param key 加密键byte数组

* @return

* @throws Exception

*/

public static String encrypt(String data, String key) throws Exception {

byte[] bt = encrypt(data.getBytes(), key.getBytes());

String strs = new BASE64Encoder().encode(bt);

return strs;

}

/**

* Description 根据键值进行解密

* @param data

* @param key 加密键byte数组

* @return

* @throws IOException

* @throws Exception

*/

public static String decrypt(String data, String key) throws IOException,

Exception {

if (data == null)

return null;

BASE64Decoder decoder = new BASE64Decoder();

byte[] buf = decoder.decodeBuffer(data);

byte[] bt = decrypt(buf,key.getBytes());

return new String(bt);

}

/**

* Description 根据键值进行加密

* @param data

* @param key 加密键byte数组

* @return

* @throws Exception

*/

private static byte[] encrypt(byte[] data, byte[] key) throws Exception {

// 生成一个可信任的随机数源

SecureRandom sr = new SecureRandom();

// 从原始密钥数据创建DESKeySpec对象

DESKeySpec dks = new DESKeySpec(key);

// 创建一个密钥工厂，然后用它把DESKeySpec转换成SecretKey对象

SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(DES);

SecretKey securekey = keyFactory.generateSecret(dks);

// Cipher对象实际完成加密操作

Cipher cipher = Cipher.getInstance(DES);

// 用密钥初始化Cipher对象

cipher.init(Cipher.ENCRYPT_MODE, securekey, sr);

return cipher.doFinal(data);

}

/**

* Description 根据键值进行解密

* @param data

* @param key 加密键byte数组

* @return

* @throws Exception

*/

private static byte[] decrypt(byte[] data, byte[] key) throws Exception {

// 生成一个可信任的随机数源

SecureRandom sr = new SecureRandom();

// 从原始密钥数据创建DESKeySpec对象

DESKeySpec dks = new DESKeySpec(key);

// 创建一个密钥工厂，然后用它把DESKeySpec转换成SecretKey对象

SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(DES);

SecretKey securekey = keyFactory.generateSecret(dks);

// Cipher对象实际完成解密操作

Cipher cipher = Cipher.getInstance(DES);

// 用密钥初始化Cipher对象

cipher.init(Cipher.DECRYPT_MODE, securekey, sr);

return cipher.doFinal(data);

}

}