code: public static String md5(byte[] data, byte[] salt) {
          if (data == null || salt == null) return null;
          byte[] dataSalt = new byte[data.length + salt.length];
          System.arraycopy(data, 0, dataSalt, 0, data.length);
          System.arraycopy(salt, 0, dataSalt, data.length, salt.length);
          return bytes2HexString(md5ToByte(dataSalt));
      }
docs: MD5加密
  
  @param data 明文字节数组
  @param salt 盐字节数组
  @return 16进制加盐密文