<!-- MD5 -->

        <dependency>

            <groupId>org.apache.commons</groupId>

            <artifactId>commons-lang3</artifactId>

            <version>3.3.2</version>

        </dependency>

public static byte[] digest(String signStr) {

        MessageDigest md5Instance = null;

        try {

            md5Instance = MessageDigest.getInstance("MD5");

            md5Instance.update(signStr.getBytes("utf-8"));

        } catch (NoSuchAlgorithmException e) {

            e.printStackTrace();

        } catch (UnsupportedEncodingException e) {

            e.printStackTrace();

        }

        return md5Instance.digest();

    }

//加密后转

        private static String byte2Hex(byte[] bytes) {

            char hexDigits[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };

            int j = bytes.length;

            char str[] = new char[j * 2];

            int k = 0;

            for (byte byte0 : bytes) {

                str[k++] = hexDigits[byte0 >>> 4 & 0xf];

                str[k++] = hexDigits[byte0 & 0xf];

            }

            return new String(str);

        }