Des加密类

需要导入Base64.jar包

import java.io.IOException;

import java.security.SecureRandom;

import javax.crypto.Cipher;

import javax.crypto.SecretKey;

import javax.crypto.SecretKeyFactory;

import javax.crypto.spec.DESKeySpec;

import Decoder.BASE64Decoder;

import Decoder.BASE64Encoder;

public class Des {

   private final static String DES = "DES";

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

      String data = "强大的黑马51期";

      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);

   }

}