Java之MD5加密

package com.troy.jpa.util;import java.security.MessageDigest;public class MD5Util {    private static final char[] DIGITS_LOWER = new char[]{'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};    //通过MD5进行加密    public static String encrpytionByMd5(String data) throws Exception {        //获取MD5的摘要        MessageDigest messageDigest = MessageDigest.getInstance("MD5");        //使用指定的直接更新摘要        messageDigest.update(data.getBytes());        //获取计算过后的数据        byte[] digest = messageDigest.digest();        //将密文转成32为，输出成字符串        return new String(encodeHex(digest));    }    //字节数据装换    private static char[] encodeHex(byte[] data) {        //获取数据字节长度        int n = data.length;        //a << b 的意思就是a*2的b次方，>>就是除以        char[] out = new char[n << 1];        int i = 0;        for(int v = 0; i < n; ++i) {            out[v++] = DIGITS_LOWER[(240 & data[i]) >>> 4];            out[v++] = DIGITS_LOWER[15 & data[i]];        }        return out;    }    public static void main(String[] args) {       try {           String data = "123456";           String md5 = encrpytionByMd5(data);           System.out.println(md5);       } catch (Exception e) {           e.printStackTrace();       }    }}