/*在java中调用sun公司提供的3DES加密解密算法时，需要使用到$JAVA_HOME/jre/lib/目录下如下的4个jar包：jce.jarsecurity/US_export_policy.jarsecurity/local_policy.jarext/sunjce_provider.jar
 Java运行时会自动加载这些包，因此对于带main函数的应用程序不需要设置到CLASSPATH环境变量中。对于WEB应用，不需要把这些包加到WEB-INF/lib目录下。
 以下是java中调用sun公司提供的3DES加密解密算法的样本代码：
 */
package com.aaa.aaa;

import java.security.*;
import javax.crypto.*;
import javax.crypto.spec.SecretKeySpec;

public class ThreeDES {
 private static final String Algorithm = "DESede"; // 定义 加密算法,可用

 // DES,DESede,Blowfish

 private static final byte[] keyBase = { 0x11, 0x22, 0x4F, 0x58,
   (byte) 0x88, 0x10, 0x40, 0x38, 0x28, 0x25, 0x79, 0x51, (byte) 0xCB,
   (byte) 0xDD, 0x55, 0x66, 0x77, 0x29, 0x74, (byte) 0x98, 0x30, 0x40,
   0x36, (byte) 0xE2 };  // 24个byte的密钥
 
 // keybyte为加密密钥，长度为24字节
 // src为被加密的数据缓冲区（源）
 /**
  * 加密
  */
 public static byte[] encryptMode(byte[] src) {
  try {// 生成密钥
   SecretKey deskey = new SecretKeySpec(keyBase, Algorithm);
   // 加密
   Cipher c1 = Cipher.getInstance(Algorithm);
   c1.init(Cipher.ENCRYPT_MODE, deskey);
   return c1.doFinal(src);
  } catch (java.security.NoSuchAlgorithmException e1) {
   e1.printStackTrace();
  } catch (javax.crypto.NoSuchPaddingException e2) {
   e2.printStackTrace();
  } catch (java.lang.Exception e3) {
   e3.printStackTrace();
  }
  return null;
 }

 // keybyte为加密密钥，长度为24字节
 // src为加密后的缓冲区
 public static byte[] decryptMode(byte[] src) {
  try { // 生成密钥
   SecretKey deskey = new SecretKeySpec(keyBase, Algorithm);
   // 解密
   Cipher c1 = Cipher.getInstance(Algorithm);
   c1.init(Cipher.DECRYPT_MODE, deskey);
   return c1.doFinal(src);
  } catch (java.security.NoSuchAlgorithmException e1) {
   e1.printStackTrace();
  } catch (javax.crypto.NoSuchPaddingException e2) {
   e2.printStackTrace();
  } catch (java.lang.Exception e3) {
   e3.printStackTrace();
  }
  return null;
 }

 // 转换成十六进制字符串
 public static String byte2hex(byte[] b) {
  String hs = "";
  String stmp = "";
  for (int n = 0; n < b.length; n++) {
   stmp = (java.lang.Integer.toHexString(b[n] & 0XFF));
   if (stmp.length() == 1)
    hs = hs + "0" + stmp;
   else
    hs = hs + stmp;
   if (n < b.length - 1)
    hs = hs + ":";
  }
  return hs.toUpperCase();
 }

 public static void main(String[] args) {
  // 添加新安全算法,如果用JCE就要把它添加进去
  Security.addProvider(new com.sun.crypto.provider.SunJCE());
  final byte[] keyBytes = { 0x11, 0x22, 0x4F, 0x58, (byte) 0x88, 0x10,
    0x40, 0x38, 0x28, 0x25, 0x79, 0x51, (byte) 0xCB, (byte) 0xDD,
    0x55, 0x66, 0x77, 0x29, 0x74, (byte) 0x98, 0x30, 0x40, 0x36,
    (byte) 0xE2 };
  // 24字节的密钥
  String szSrc = "This is a 3DES test. 测试";
  System.out.println("加密前的字符串:" + szSrc);
  byte[] encoded = encryptMode(szSrc.getBytes());
  System.out.println("加密后的字符串:" + new String(encoded));
  byte[] srcBytes = decryptMode(encoded);
  System.out.println("解密后的字符串:" + (new String(srcBytes)));
 }

}