使用Java實作TripleDES之加密、解密功能!

package com.nelson.util;




import java.security.Key;

import java.security.InvalidKeyException;

import java.security.spec.InvalidKeySpecException;

import java.security.NoSuchAlgorithmException;

import javax.crypto.Cipher;

import javax.crypto.SecretKeyFactory;

import javax.crypto.spec.DESedeKeySpec;

import javax.crypto.BadPaddingException;

import javax.crypto.NoSuchPaddingException;

import javax.crypto.IllegalBlockSizeException;

import java.io.UnsupportedEncodingException;

import java.io.IOException;

import sun.misc.BASE64Encoder;

import sun.misc.BASE64Decoder;




/**

 * 此類別提供TripleDES之加解密功能.

 * 

 * 文件建立日期：2009/10/08

 * @author Nelson Chen

 */

public class DESedeEncryption {

 private static String algorithm = "DESede";

 private static Key key = null;

 private static Cipher cipher = null;

 private static SecretKeyFactory keyFactory = null;

 private static DESedeKeySpec keySpec = null;




 /**

  * 此method切始化加解密之共用鑰匙，其中產生共用之鑰匙規範可以自己決定。  * 

  * @param chartCode 文字編碼:UTF-8,UTF-16

  * @param strKeySpec 欲產生共用鑰匙之規範，其長度需大約24。

  * @throws NoSuchAlgorithmException

  * @throws UnsupportedEncodingException

  * @throws InvalidKeyException

  * @throws InvalidKeySpecException

  * @throws NoSuchPaddingException

  */

 private static void setUp(String chartCode,String strKeySpec)

  throws NoSuchAlgorithmException,

      UnsupportedEncodingException,

      InvalidKeyException,

      InvalidKeySpecException,

      NoSuchPaddingException{

  keyFactory = SecretKeyFactory.getInstance(algorithm);

  if(strKeySpec==null || strKeySpec.equals("")){

   //若沒有提供鑰匙規範，則改以下面之值取代！

   strKeySpec = "Your secret Key phrase!!";

  }

  keySpec = new DESedeKeySpec(strKeySpec.getBytes(chartCode));

  key = keyFactory.generateSecret(keySpec);

  cipher = Cipher.getInstance(algorithm);

 }

 

 /**

  * 此method之功能為加密

  * @param input 欲加密之文字

  * @param chartCode 文字編碼:UTF-8,UTF-16

  * @param strKeySpec 欲產生共用鑰匙之規範，其長度需大約24。

  * @return 回傳加密後之文字

  * @throws InvalidKeyException

  * @throws BadPaddingException

  * @throws IllegalBlockSizeException

  * @throws UnsupportedEncodingException

  * @throws NoSuchPaddingException

  * @throws InvalidKeySpecException

  * @throws NoSuchAlgorithmException

  */

 public static String encrypt(String input,String chartCode,String strKeySpec)

  throws InvalidKeyException,

         BadPaddingException,

         IllegalBlockSizeException,

         UnsupportedEncodingException,

         NoSuchPaddingException,

         InvalidKeySpecException,

         NoSuchAlgorithmException{

  DESedeEncryption.setUp(chartCode,strKeySpec);

  cipher.init(Cipher.ENCRYPT_MODE, key);  

  byte[] bAInput = input.getBytes(chartCode);

  return (new BASE64Encoder()).encode(cipher.doFinal(bAInput));

 }

 

 /**

  * 此method之功能解密

  * @param encryptString 加密後之文字

  * @param chartCode 文字編碼:UTF-8,UTF-16

  * @param strKeySpec 欲產生共用鑰匙之規範，其長度需大約24。

  * @return 回傳解密後之文字

  * @throws InvalidKeyException

  * @throws BadPaddingException

  * @throws IllegalBlockSizeException

  * @throws UnsupportedEncodingException

  * @throws IOException

  * @throws NoSuchPaddingException

  * @throws InvalidKeySpecException

  * @throws NoSuchAlgorithmException

  */

 public static String decrypt(String encryptString,String chartCode,String strKeySpec)

     throws InvalidKeyException,

            BadPaddingException,

            IllegalBlockSizeException,

            UnsupportedEncodingException,

            IOException,

            NoSuchPaddingException,

         InvalidKeySpecException,

         NoSuchAlgorithmException{

  DESedeEncryption.setUp(chartCode,strKeySpec);

  cipher.init(Cipher.DECRYPT_MODE, key);

  byte[] bPlanText = cipher.doFinal((new BASE64Decoder()).decodeBuffer(encryptString));

  return new String(bPlanText,chartCode);

 }

 

 /**

  * 驗證加密、解密功能是否正確!!

  */

 public static void main(String[] args){

  String input = "Nelson111111";

  String chartCode = "UTF-8";

  String strKeySpec = null;

  String strKeySpec1 = "222222222222222222222222";

  try{

   String strEncrption = encrypt(input,chartCode,strKeySpec);

   String strDecrption = decrypt(strEncrption,chartCode,strKeySpec);

   System.out.println("Input:"+input+",Encryption:"+strEncrption);

   System.out.println("Input:"+input+",Decryption:"+strDecrption);

   strEncrption = encrypt(input,chartCode,strKeySpec1);

   strDecrption = decrypt(strEncrption,chartCode,strKeySpec1);

   System.out.println("Input:"+input+",Encryption:"+strEncrption);

   System.out.println("Input:"+input+",Decryption:"+strDecrption);  

  }catch(Exception e){

   e.printStackTrace();

   System.out.println(e.getMessage());

  }

 }

}