EncryptUtil加密工具类

package cloud.simple.service.util;

import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;

/**
 * 
概要:
 
 *    加密工具类
 * 

 * 
功能:
 * 

 *        
提供md5\sha1\base64\3des 加密
 * 
 * 

 * 
 */
public class EncryptUtil {

    private EncryptUtil() {}
    /*========================================================================================*/
    /*===================================BASE64 部分===========================================*/
    private static final byte[] DECODE_TABLE = new byte[] { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 62, 0, 0, 0, 63, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 0,
            0, 0, 0, 0, 0, 0, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 0, 0, 0, 0, 0, 0, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 0,
            0, 0, 0, 0 };

    // "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/ "
    private static final byte[] ENCODE_TABLE = new byte[] { 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113,
            114, 115, 116, 117, 118, 119, 120, 121, 122, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 43, 47 };

    static {
        int index = 0;
        for (char c = 'A'; c <= 'Z'; c++)
            ENCODE_TABLE[index++] = (byte) c;
        for (char c = 'a'; c <= 'z'; c++)
            ENCODE_TABLE[index++] = (byte) c;
        for (char c = '0'; c <= '9'; c++)
            ENCODE_TABLE[index++] = (byte) c;
        ENCODE_TABLE[index++] = (byte) '+';
        ENCODE_TABLE[index++] = (byte) '/';

        // create decode table
        for (int i = 0; i < 64; i++)
            DECODE_TABLE[ENCODE_TABLE[i]] = (byte) i;
    }

    /**
     * base64加密
     * 每个参数，返回值注明含义
     * @param data
     * @return
     */
    public static byte[] Base64Encode(byte[] data) {
        if (data == null)
            return null;

        int fullGroups = data.length / 3;
        int resultBytes = fullGroups * 4;
        if (data.length % 3 != 0)
            resultBytes += 4;

        byte[] result = new byte[resultBytes];
        int resultIndex = 0;
        int dataIndex = 0;
        int temp = 0;
        for (int i = 0; i < fullGroups; i++) {
            temp = (data[dataIndex++] & 0xff) << 16 | (data[dataIndex++] & 0xff) << 8 | data[dataIndex++] & 0xff;

            result[resultIndex++] = ENCODE_TABLE[(temp >> 18) & 0x3f];
            result[resultIndex++] = ENCODE_TABLE[(temp >> 12) & 0x3f];
            result[resultIndex++] = ENCODE_TABLE[(temp >> 6) & 0x3f];
            result[resultIndex++] = ENCODE_TABLE[temp & 0x3f];
        }
        temp = 0;
        while (dataIndex < data.length) {
            temp <<= 8;
            temp |= data[dataIndex++] & 0xff;
        }
        switch (data.length % 3) {
        case 1:
            temp <<= 8;
            temp <<= 8;
            result[resultIndex++] = ENCODE_TABLE[(temp >> 18) & 0x3f];
            result[resultIndex++] = ENCODE_TABLE[(temp >> 12) & 0x3f];
            result[resultIndex++] = 0x3D;
            result[resultIndex++] = 0x3D;
            break;
        case 2:
            temp <<= 8;
            result[resultIndex++] = ENCODE_TABLE[(temp >> 18) & 0x3f];
            result[resultIndex++] = ENCODE_TABLE[(temp >> 12) & 0x3f];
            result[resultIndex++] = ENCODE_TABLE[(temp >> 6) & 0x3f];
            result[resultIndex++] = 0x3D;
            break;
        default:
            break;
        }

        return result;
    }

    /**
     * 概要：
     * base64解密 
     * @param base64Data
     * @return
     */
    public static byte[] Base64Decode(byte[] base64Data) {
        if (base64Data == null)
            return null;
        if (base64Data.length == 0)
            return new byte[0];
        if (base64Data.length % 4 != 0)
            throw new IllegalArgumentException("数据不完整，长度为： " + base64Data.length);

        byte[] result = null;
        int groupCount = base64Data.length / 4;

        int lastData = base64Data.length;
        while (base64Data[lastData - 1] == 0x3D) {
            if (--lastData == 0)
                return new byte[0];
        }
        result = new byte[lastData - groupCount];

        int temp = 0;
        int resultIndex = 0;
        int dataIndex = 0;
        for (; dataIndex + 4 < base64Data.length;) {
            temp = DECODE_TABLE[base64Data[dataIndex++]];
            temp = (temp << 6) + DECODE_TABLE[base64Data[dataIndex++]];
            temp = (temp << 6) + DECODE_TABLE[base64Data[dataIndex++]];
            temp = (temp << 6) + DECODE_TABLE[base64Data[dataIndex++]];

            result[resultIndex++] = (byte) ((temp >> 16) & 0xff);
            result[resultIndex++] = (byte) ((temp >> 8) & 0xff);
            result[resultIndex++] = (byte) (temp & 0xff);
        }

        temp = 0;
        int j = 0;
        for (; dataIndex < base64Data.length; dataIndex++, j++)
            temp = (temp << 6) + DECODE_TABLE[base64Data[dataIndex]];
        for (; j < 4; j++)
            temp <<= 6;

        result[resultIndex++] = (byte) ((temp >> 16) & 0xff);
        if (base64Data[dataIndex - 2] != '=')
            result[resultIndex++] = (byte) ((temp >> 8) & 0xff);
        if (base64Data[dataIndex - 1] != '=')
            result[resultIndex++] = (byte) (temp & 0xff);

        return result;
    }

    /*===================================BASE64 部分===========================================*/
    /*========================================================================================*/
    
    /*========================================================================================*/
    /*===================================MD5 部分==============================================*/
    
    private final static String[] hexDigits = { 
        "0", "1", "2", "3", "4", "5", "6", "7", 
        "8", "9", "A", "B", "C", "D", "E", "F"}; 

    /** 
     * 转换字节数组为16进制字串 
     * @param b 字节数组 
     * @return 16进制字串 
     */ 

    public static String byteArrayToHexString(byte[] b) { 
      StringBuffer resultSb = new StringBuffer(); 
      for (int i = 0; i < b.length; i++) { 
        resultSb.append(byteToHexString(b[i])); 
      } 
      return resultSb.toString(); 
    } 

    /**
     * 转换字节数组为16进制字符串
     * @param b
     * @return
     */
    private static String byteToHexString(byte b) { 
      int n = b; 
      if (n < 0) 
        n = 256 + n; 
      int d1 = n / 16; 
      int d2 = n % 16; 
      return hexDigits[d1] + hexDigits[d2]; 
    } 
    
    /**
     * 概要：
     * MD5 摘要计算
     * TODO 每个参数，返回值注明含义
     * @param src
     * @return
     * @throws Exception
     */
   public static byte[] md5Digest(byte[] src) throws Exception {
      java.security.MessageDigest alg = java.security.MessageDigest
            .getInstance("MD5"); // MD5 is 16 bit message digest

      return alg.digest(src);
   }

   /**
    * 概要：
    * MD5 摘要计算
    * @param src
    * @return
    * @throws Exception
    */
   public static String md5Digest(String src) throws Exception {
      return byteArrayToHexString(md5Digest((src.getBytes("UTF-8"))));
   }

   /*===================================MD5 部分==============================================*/
    /*========================================================================================*/

    /*========================================================================================*/
   /*===================================SHA1 部分==============================================*/
   
   /**
    * 实现SHA-1消息摘要
    * @param inStr 
    * @return 成功，返回摘要，失败，返回null
    */
   public static String sha1(String inStr) {
      String outStr = null;
      try {
         outStr = EncryptUtil.digest(inStr.getBytes("UTF-8"), "SHA-1");
      } catch (UnsupportedEncodingException e) {
      } catch (Exception e) {
      }
      return outStr;
   }
   /**
    * 实现SHA-256消息摘要
    * @param inStr 
    * @return 成功，返回摘要，失败，返回null
    */
   public static String sha256(String inStr) {
      String outStr = null;
      try {
         outStr = EncryptUtil.digest(inStr.getBytes("UTF-8"), "SHA-256");
      } catch (UnsupportedEncodingException e) {
      } catch (Exception e) {
      }
      return outStr;
   }
   public static String digest(byte[] inputBytes, String algorithm) {
      String outputStr = null;
      try {
         MessageDigest alg = MessageDigest.getInstance(algorithm);
         alg.update(inputBytes);
         byte[] digest = alg.digest();
         outputStr = byte2hex(digest);
      } catch (NoSuchAlgorithmException ex) {
      }
      return outputStr;
   }
   
   /**
    * 二进制转十六进制字符串。每一个字节转为两位十六进制字符串。
    */
   public static String byte2hex(byte[] b) {
      String hs = "";
      String stmp = "";
      for (int i = 0; i < b.length; i++) {
         stmp = Integer.toHexString(b[i] & 0XFF);
         if (stmp.length() == 1) {
            hs = hs + "0" + stmp;
         } else {
            hs = hs + stmp;
         }
      }
      return hs.toUpperCase();
   }

   /*===================================SHA1 部分==============================================*/
    /*========================================================================================*/

   /*========================================================================================*/
    /*===================================3DES 部分=============================================*/

   private static final String CRYPT_ALGORITHM = "DESede";
   /**
    * 3DES加密模式
    */
    public static String encrypt(String value,String key) {
        try {
            SecretKeySpec keySpec = new SecretKeySpec(key.getBytes(), CRYPT_ALGORITHM);
            Cipher cipher = Cipher.getInstance(CRYPT_ALGORITHM);
            cipher.init(Cipher.ENCRYPT_MODE, keySpec);
            byte[] encryptedByte = cipher.doFinal(value.getBytes());
            String encodedByte = byte2hex(encryptedByte);
            return encodedByte;
        } catch(Exception e) {
            e.printStackTrace();
            return null;
        }
    }
    
    /**
     * 概要：
     * 3DES解密
     * @param value
     * @param key
     * @return
     */
   public static String decrypt(String value,String key) {
        try {
           
            SecretKeySpec keySpec = new SecretKeySpec(key.getBytes(), CRYPT_ALGORITHM);
            Cipher cipher = Cipher.getInstance(CRYPT_ALGORITHM);
            cipher.init(Cipher.DECRYPT_MODE, keySpec);
            byte[] decryptedByte = cipher.doFinal(hex2byte(value));            
            return new String(decryptedByte);
        } catch(Exception e) {
           e.printStackTrace();
            return null;
        }
        }
    
   /**
    * 概要：
    * 十六进制转二进制
    * @param hex
    * @return
    * @throws IllegalArgumentException
    */
   public static byte[] hex2byte(String hex) throws IllegalArgumentException {
      if (hex.length() % 2 != 0) {
         throw new IllegalArgumentException();
      }
      if (hex.startsWith("0x")) {
         hex = hex.substring(2);
      }
      char[] arr = hex.toCharArray();
      byte[] b = new byte[hex.length() / 2];
      for (int i = 0, j = 0, l = hex.length(); i < l; i++, j++) {
         String swap = "" + arr[i++] + arr[i];
         int byteint = Integer.parseInt(swap, 16) & 0xFF;
         b[j] = new Integer(byteint).byteValue();
      }
      return b;
   }
   /*===================================3DES 部分=============================================*/
   /*========================================================================================*/
   
   
   /**
    * cookie加密
    * @param data 数据
    * @param key 指定密匙
    * @return     返回编码base64后的结果
    */
   public static String encryptBase64(String data, String key) {
      String value = EncryptUtil.encrypt(data, key);
      return new String(EncryptUtil.Base64Encode(value.getBytes()));
   }
   
   /**
    * cookie 解密
    * @param data 数据
    * @param key 指定密匙
    * @return 返回解密后的源数据
    */
   public static String decryptBase64(String data, String key) {
      data = new String(EncryptUtil.Base64Decode(data.getBytes()));
      String value = EncryptUtil.decrypt(data, key);
      return value;
   }
}