MD5算法

 public static String md5(String string) {     byte[] hash;      try {          hash = MessageDigest.getInstance("MD5").digest(string.getBytes("UTF-8"));      } catch (NoSuchAlgorithmException e) {          throw new RuntimeException("Huh, MD5 should be supported?", e);      } catch (UnsupportedEncodingException e) {          throw new RuntimeException("Huh, UTF-8 should be supported?", e);      }      StringBuilder hex = new StringBuilder(hash.length * 2);      for (byte b : hash) {          if ((b & 0xFF) < 0x10) hex.append("0");          hex.append(Integer.toHexString(b & 0xFF));      }      return hex.toString();  }