关于 MD5加密 解密

 /**

     * MD5加密

     * @param str

     * @return

     */

    public static String md5Encode(String str) {

        StringBuffer buf = new StringBuffer();

        try {

            MessageDigest md5 = MessageDigest.getInstance("MD5");

            md5.update(str.getBytes());

            byte bytes[] = md5.digest();

            for (int i = 0; i < bytes.length; i++) {

                String s = Integer.toHexString(bytes[i] & 0xff);

                if (s.length() == 1) {

                    buf.append("0");

                }

                buf.append(s);

            }



        } catch (Exception ex) {

        }

        return buf.toString();

    }