code: public static String md5(Object content) {
  		String keys = null;
  		if (content == null) {
  			return null;
  		}
  		try {
  			MessageDigest md = MessageDigest.getInstance(MD5_NAME);
  			byte[] bPass = String.valueOf(content).getBytes(CARTSET_UTF_8);
  			md.update(bPass);
  			keys = bytesToHexString(md.digest());
  		} catch (NoSuchAlgorithmException aex) {
  			System.out.println(aex);
  		} catch (java.io.UnsupportedEncodingException uex) {
  			System.out.println(uex);
  		}
  		return keys.toLowerCase();
  	}
docs: MD5加密
  @param content
  @return