java中DES加密解密

废话不多说，直接奉上代码：

代码一

package com.eabax.plugin.yundada.utils;

import java.io.IOException;

import java.security.InvalidKeyException;

import java.security.NoSuchAlgorithmException;

import java.security.SecureRandom;

import java.security.spec.InvalidKeySpecException;

import javax.crypto.BadPaddingException;

import javax.crypto.Cipher;

import javax.crypto.IllegalBlockSizeException;

import javax.crypto.NoSuchPaddingException;

import javax.crypto.SecretKey;

import javax.crypto.SecretKeyFactory;

import javax.crypto.spec.DESKeySpec;

import org.apache.commons.codec.binary.Base64;

import sun.misc.BASE64Decoder;

public class DESEncryptHelper {

  private final static String DES = "DES";

  /**

   * 生成密钥

   * @param employeeCode

   */

  public static String getDESKey(String encryptStr){

    if (!CacheManager.getCache().containsKey("encryptKey_"+encryptStr)) {

      CacheManager.getCache().put("encryptKey_"+encryptStr, encryptStr+"tablemiyaokey");

    }

    String key = (String) CacheManager.getCache().get("encryptKey_"+encryptStr);

    return key;

  }

   /**

   * 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);

  }

  /**

   * 对字符串加密

   * @param str

   * @return

   * @throws InvalidKeyException

   * @throws IllegalBlockSizeException

   * @throws BadPaddingException

   * @throws InvalidKeySpecException

   * @throws NoSuchAlgorithmException

   * @throws NoSuchPaddingException

   */

  public static String getEncryptStr(String str,String encryptStr) throws InvalidKeyException,

      IllegalBlockSizeException, BadPaddingException,

      InvalidKeySpecException, NoSuchAlgorithmException,

      NoSuchPaddingException {

    //获取key

    String key = getDESKey(encryptStr);

    //获取密钥

    SecretKeyFactory factory = SecretKeyFactory.getInstance("DES");

    DESKeySpec keyspec = new DESKeySpec(key.getBytes());

    SecretKey deskey = factory.generateSecret(keyspec);

    // Cipher负责完成加密或解密工作

    Cipher c = Cipher.getInstance("DES");

    // 根据密钥，对Cipher对象进行初始化，DECRYPT_MODE表示加密模式

    c.init(Cipher.ENCRYPT_MODE, deskey);

    byte[] src = str.getBytes();

    // 该字节数组负责保存加密的结果

    byte[] cipherByte = c.doFinal(src);

    String enstr = new String(Base64.encodeBase64(cipherByte));

    return enstr;

  }

   /**

   * 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);

  }

}

代码二

package com.sinosoft.olyvem.common;



import java.security.SecureRandom;



import javax.crypto.Cipher;

import javax.crypto.SecretKey;

import javax.crypto.SecretKeyFactory;

import javax.crypto.spec.DESKeySpec;



import sun.misc.BASE64Encoder;



public class DES ...{

  private byte[] desKey;



  public DES(byte[] desKey) ...{

    this.desKey = desKey;

  }



  public byte[] doEncrypt(byte[] plainText) throws Exception ...{

    // DES算法要求有一个可信任的随机数源

    SecureRandom sr = new SecureRandom();

    byte rawKeyData[] = desKey;/**//* 用某种方法获得密匙数据 */

    // 从原始密匙数据创建DESKeySpec对象

    DESKeySpec dks = new DESKeySpec(rawKeyData);

    // 创建一个密匙工厂，然后用它把DESKeySpec转换成

    // 一个SecretKey对象

    SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");

    SecretKey key = keyFactory.generateSecret(dks);

    // Cipher对象实际完成加密操作

    Cipher cipher = Cipher.getInstance("DES");

    // 用密匙初始化Cipher对象

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

    // 现在，获取数据并加密

    byte data[] = plainText;/**//* 用某种方法获取数据 */

    // 正式执行加密操作

    byte encryptedData[] = cipher.doFinal(data);

    return encryptedData;

  }



  public byte[] doDecrypt(byte[] encryptText) throws Exception ...{

    // DES算法要求有一个可信任的随机数源

    SecureRandom sr = new SecureRandom();

    byte rawKeyData[] = desKey; /**//* 用某种方法获取原始密匙数据 */

    // 从原始密匙数据创建一个DESKeySpec对象

    DESKeySpec dks = new DESKeySpec(rawKeyData);

    // 创建一个密匙工厂，然后用它把DESKeySpec对象转换成

    // 一个SecretKey对象

    SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");

    SecretKey key = keyFactory.generateSecret(dks);

    // Cipher对象实际完成解密操作

    Cipher cipher = Cipher.getInstance("DES");

    // 用密匙初始化Cipher对象

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

    // 现在，获取数据并解密

    byte encryptedData[] = encryptText;/**//* 获得经过加密的数据 */

    // 正式执行解密操作

    byte decryptedData[] = cipher.doFinal(encryptedData);

    return decryptedData;

  }



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

    String key = "FtpXPass";

    String value = "olympic";

    BASE64Encoder base64Encoder = new BASE64Encoder();



    DES desEncrypt = new DES(key.getBytes());

    byte[] encryptText = desEncrypt.doEncrypt(value.getBytes());

    //System.out.println("doEncrypt  -  " + toHexString(encryptText));

    System.out.println("doEncrypt  -  "

        + base64Encoder.encode(encryptText));

    byte[] decryptText = desEncrypt.doDecrypt("r9NGYcKAtdo=".getBytes());

    System.out.println("doDecrypt  -  " + new String(decryptText));

    //System.out.println("doDecrypt  -  " + toHexString(decryptText));



  }



  public static String toHexString(byte[] value) ...{

    String newString = "";

    for (int i = 0; i < value.length; i++) ...{

      byte b = value[i];

      String str = Integer.toHexString(b);

      if (str.length() > 2) ...{

        str = str.substring(str.length() - 2);

      }

      if (str.length() < 2) ...{

        str = "0" + str;

      }

      newString += str;

    }

    return newString.toUpperCase();

  }



}