/*字符串 DESede(3DES) 加密*/
import java.security.Security;
import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;
import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;

public class DES3 {

 private static final String Algorithm = "DESede"; //定義加密算法,可用

 // DES,DESede,Blowfish

 // keybyte為加密密鑰，長度為24字節
 // src為被加密的數據緩沖區（源）
 public static String encryptMode(byte[] keybyte, byte[] src)
 {
  try
  {
   // 生成密鑰
   SecretKey deskey = new SecretKeySpec(keybyte, Algorithm);
   // 加密
   Cipher c1 = Cipher.getInstance(Algorithm);
   c1.init(Cipher.ENCRYPT_MODE, deskey);
   // 開始加密運算
   byte[] encryptedByteArray = c1.doFinal(src);
   // 加密運算之后 將byte[]轉化為base64的String
   BASE64Encoder enc = new BASE64Encoder();
   return enc.encode(encryptedByteArray);
  }
  catch (java.security.NoSuchAlgorithmException e1)
  {
   e1.printStackTrace();
  }
  catch (javax.crypto.NoSuchPaddingException e2)
  {
   e2.printStackTrace();
  }
  catch (java.lang.Exception e3)
  {
   e3.printStackTrace();
  }
  return null;
 }

 // keybyte為加密密鑰，長度為24字節
 // src為加密后的緩沖區
 public static byte[] decryptMode(byte[] keybyte, String src)
 {
  try {
   // 生成密鑰
   SecretKey deskey = new SecretKeySpec(keybyte, Algorithm);
   // 解密
   Cipher c1 = Cipher.getInstance(Algorithm);
   c1.init(Cipher.DECRYPT_MODE, deskey);
   // 解密運算之前
   BASE64Decoder dec = new BASE64Decoder();
   byte[] encryptedByteArray = dec.decodeBuffer(src);
   // 解密運算 將base64的String轉化為byte[]
   return c1.doFinal(encryptedByteArray);

  } catch (java.security.NoSuchAlgorithmException e1) {
   e1.printStackTrace();
  } catch (javax.crypto.NoSuchPaddingException e2) {
   e2.printStackTrace();
  } catch (java.lang.Exception e3) {
   e3.printStackTrace();
  }
  return null;
 }

 // 轉換成十六進制字符串
 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就要把它添加進去
  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字節的密鑰

  String szSrc = "This is a 3DES test. 測試";
  System.out.println("加密前的字符串:" + szSrc);

  String encoded = encryptMode(keyBytes, szSrc.getBytes());
  System.out.println("加密后的字符串:" + encoded);

  byte[] srcBytes = decryptMode(keyBytes, encoded);
  System.out.println("解密后的字符串:" + (new String(srcBytes)));
 }
}