周末给女友讲了遍加密算法，没想到...

/** 
 * MD5加密 
 *  
 * @param data 
 * @return 
 * @throws Exception 
 */  
public static byte[] encryptMD5(byte[] data) throws Exception {  
    MessageDigest md5 = MessageDigest.getInstance(KEY_MD5);  
    md5.update(data);  
    return md5.digest();  
}

/** 
* SHA加密 
*  
* @param data 
* @return 
* @throws Exception 
*/  
public static byte[] encryptSHA(byte[] data) throws Exception {  
    MessageDigest sha = MessageDigest.getInstance(KEY_SHA);  
    sha.update(data);  
    return sha.digest();  
    }  
}

/** 
 * 初始化HMAC密钥 
 *  
 * @return 
 * @throws Exception 
 */  
public static String initMacKey() throws Exception {  
    KeyGenerator keyGenerator = KeyGenerator.getInstance(KEY_MAC);  
    SecretKey secretKey = keyGenerator.generateKey();  
    return encryptBASE64(secretKey.getEncoded());  
}  
/** 
 * HMAC加密 
 *  
 * @param data 
 * @param key 
 * @return 
 * @throws Exception 
 */  
public static byte[] encryptHMAC(byte[] data, String key) throws Exception {  
    SecretKey secretKey = new SecretKeySpec(decryptBASE64(key), KEY_MAC);  
    Mac mac = Mac.getInstance(secretKey.getAlgorithm());  
    mac.init(secretKey);  
    return mac.doFinal(data);  
}

/**
  * 加密
  *
  * @param datasource 待加密数据
  * @param key
  * @return byte数组
  */
  public static byte[] enCrypto(byte[] datasource, String key) throws InvalidKeyException, NoSuchAlgorithmException, InvalidKeySpecException, NoSuchPaddingException, BadPaddingException, IllegalBlockSizeException {
    SecureRandom random = new SecureRandom();
    DESKeySpec desKey = new DESKeySpec(key.getBytes());
    // 创建一个密匙工厂，然后用它把DESKeySpec转换成
    SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
    SecretKey securekey = keyFactory.generateSecret(desKey);
    // 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, securekey, random);
    // 现在，获取数据并加密
    // 正式执行加密操作
    return cipher.doFinal(datasource);
    }

/**
  * 方法描述：3DES加密
  *
  * @param plainText  明文
  * @param secretKey  密钥
  * @param iv         加密向量
  * @return String    密文
  * @throws Exception
  */
 public static String encode(String plainText, String secretKey, String iv)
   throws Exception {
  Key deskey = null;
  DESedeKeySpec spec = new DESedeKeySpec(secretKey.getBytes());
  SecretKeyFactory keyfactory = SecretKeyFactory.getInstance("desede");
  deskey = keyfactory.generateSecret(spec);
  Cipher cipher = Cipher.getInstance("desede/CBC/PKCS5Padding");
  IvParameterSpec ips = new IvParameterSpec(iv.getBytes());
  cipher.init(Cipher.ENCRYPT_MODE, deskey, ips);
  byte[] encryptData = cipher.doFinal(plainText.getBytes(encoding));
  return Base64.encode(encryptData);
 }

/**
  * AES加密
  * @param data 要加密的字符串
  * @param key  加密key
  * @param iv   密码加密算法中的IV
  * @return 加密后的字符串
  */
  public static String encrypt(String data, String key, String iv) {
    try {
    Cipher cipher = Cipher.getInstance("AES/CBC/NoPadding");
    int blockSize = cipher.getBlockSize();
    byte[] dataBytes = data.getBytes();
    int plaintextLength = dataBytes.length;
    if (plaintextLength % blockSize != 0) {
        plaintextLength = plaintextLength + (blockSize - (plaintextLength % blockSize));
        }
          byte[] plaintext = new byte[plaintextLength];
          System.arraycopy(dataBytes, 0, plaintext, 0, dataBytes.length);
          SecretKeySpec keyspec = new SecretKeySpec(key.getBytes(), Constant.STRING_AES);
          IvParameterSpec ivspec = new IvParameterSpec(iv.getBytes(Constant.STRING_UTF_8));
          cipher.init(Cipher.ENCRYPT_MODE, keyspec, ivspec);
          byte[] encrypted = cipher.doFinal(plaintext);
          String encrypt = Base64.getEncoder().encodeToString(encrypted); //BASE64加密
          encrypt = encrypt.replaceAll(new String(Constant.STRING_CARRIAGE_RETURN), Constant.STRING_BLANK);
          encrypt = encrypt.replaceAll(new String(Constant.STRING_LINE_FEED), Constant.STRING_BLANK);
          return encrypt;
        } catch (Exception e) {
          e.printStackTrace();
          return null;
        }
    }

/**
  * RSA公钥加密
  *
  * @param str 加密字符串
  * @param publicKey 公钥
  * @return 密文
  * @throws Exception 加密过程中的异常信息
  */
  public static String encrypt( String str, String publicKey ) throws Exception{
    //base64编码的公钥
    byte[] decoded = Base64.decodeBase64(publicKey);
    RSAPublicKey pubKey = (RSAPublicKey) KeyFactory.getInstance("RSA").generatePublic(new X509EncodedKeySpec(decoded));
    //RSA加密
    Cipher cipher = Cipher.getInstance("RSA");
    cipher.init(Cipher.ENCRYPT_MODE, pubKey);
    String outStr = Base64.encodeBase64String(cipher.doFinal(str.getBytes("UTF-8")));
      return outStr;
    }

/**
 * 加密
 * @param data
 * @param publicKey
 * @return
 * @throws Exception
 */
public static byte[] encrypt(byte[] data, String publicKey)
    throws Exception {
    byte[] keyBytes = BASE64Decoder.decodeBuffer(publicKey);
    X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(keyBytes);
    KeyFactory keyFactory = KeyFactory.getInstance(ECCEnum.ALGORITHM.value());
    ECPublicKey pubKey = (ECPublicKey) keyFactory
                .generatePublic(x509KeySpec);
    Cipher cipher = new NullCipher();
    cipher.init(Cipher.ENCRYPT_MODE, pubKey);
    return cipher.doFinal(data);
}