kmall-haikong/kmall-admin/src/main/java/com/kmall/admin/haikong/utils/Md5Utils.java

package com.kmall.admin.haikong.utils;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;

/**
 * Md5加密方法
 * 
 * @author cadmin
 */
public class Md5Utils
{
    private static final Logger log = LoggerFactory.getLogger(Md5Utils.class);

    private static byte[] md5(String s)
    {
        MessageDigest algorithm;
        try
        {
            algorithm = MessageDigest.getInstance("MD5");
            algorithm.reset();
            algorithm.update(s.getBytes("UTF-8"));
            byte[] messageDigest = algorithm.digest();
            return messageDigest;
        }
        catch (Exception e)
        {
            log.error("MD5 Error...", e);
        }
        return null;
    }

    private static final String toHex(byte hash[])
    {
        if (hash == null)
        {
            return null;
        }
        StringBuffer buf = new StringBuffer(hash.length * 2);
        int i;

        for (i = 0; i < hash.length; i++)
        {
            if ((hash[i] & 0xff) < 0x10)
            {
                buf.append("0");
            }
            buf.append(Long.toString(hash[i] & 0xff, 16));
        }
        return buf.toString();
    }

    public static String hash(String s)
    {
        try
        {
            return new String(toHex(md5(s)).getBytes("UTF-8"), "UTF-8");
        }
        catch (Exception e)
        {
            log.error("not supported charset...{}", e);
            return s;
        }
    }


    /**
     * MD5加密，返回32位密文
     * @param plainText
     * @return String
     * @throws UnsupportedEncodingException
     */
    public static String encryption(String plainText){
        String re_md5 = new String();
        try {
            MessageDigest md = MessageDigest.getInstance("MD5");
            md.update(plainText.getBytes("UTF-8"));
            byte b[] = md.digest();
            int i;
            StringBuffer buf = new StringBuffer("");
            for (int offset = 0; offset < b.length; offset++) {
                i = b[offset];
                if (i < 0)
                    i += 256;
                if (i < 16)
                    buf.append("0");
                buf.append(Integer.toHexString(i));
            }
            re_md5 = buf.toString();
        } catch (Exception e) {
            e.printStackTrace();
        }
        return re_md5;
    }


}