md5值计算(java程序)

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

/**
 * @author: zhaolong 2018/8/8
 * @version: 1.0.0
 * @since: 1.0
 */
public class Md5GeneratorUtils {

    public static String getMd5(String key) throws NoSuchAlgorithmException {

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

        byte[] keyBytes = key.getBytes();

        byte[] md5Bytes = messageDigest.digest(keyBytes);

        return bytesToHex(md5Bytes);
    }

    public static String bytesToHex(byte[] bytes){
        StringBuilder sb = new StringBuilder();
        for (byte b : bytes){
            sb.append(byteToHex(b));
        }
        return sb.toString();
    }

    public static String byteToHex(byte b){
        StringBuilder sb = new StringBuilder();
        int intb = b;
        if (intb < 0){
            intb += 256;
        }
        if (intb < 16){
            sb.append(0);
        }
        sb.append(Integer.toHexString(intb));
        return sb.toString();
    }

    public static void main(String[] args) throws NoSuchAlgorithmException {
        String s = "zhaolong";
        System.out.println(getMd5(s));
    }
}