package com.hongyuan.test;

import java.security.messagedigest;

import java.security.nosuchalgorithmexception;

import java.util.random;

import java.util.uuid;

/*

* 杂项(无符号数转换，字符串补齐，md5,uuid,随机数)

*/

public class sundrytest {

//转成无符号数

public static number tounsignednumber(number num){

if(num instanceof byte){

return (byte)num & 0xff;

}else if(num instanceof short){

return (short)num & 0xffff;

}else if(num instanceof integer){

return (integer)num & 0xffffffffl;

}else{

return -1;

}

}

//左补齐

public static string leftpad(string str,string pad,int len){

string newstr=(str==null?"":str);

while(newstr.length()

newstr=pad+newstr;

}

if(newstr.length()>len){

newstr=newstr.substring(newstr.length()-len);

}

return newstr;

}

//右补齐

public static string rightpad(string str,string pad,int len){

string newstr=(str==null?"":str);

while(newstr.length()

newstr=newstr+pad;

}

if(newstr.length()>len){

newstr=newstr.substring(0, len);

}

return newstr;

}

//md5

public static string md5(string str){

stringbuilder sb=new stringbuilder();

try {

messagedigest digest = messagedigest.getinstance("md5");

byte[] message=digest.digest(str.getbytes());

for(int i=0;i

sb.append(leftpad(           //左补齐

integer.tohexstring(      //转成16进制数

(integer)tounsignednumber(message[i])), //转成无符号数

"0",2).touppercase());       //转成大写

}

} catch (nosuchalgorithmexception e) {

throw new runtimeexception("不存在md5服务！");

}

return sb.tostring();

}

//uuid

public static string uuid(){

return uuid.randomuuid().tostring().replaceall("-","").touppercase();

}

//随机数(包括min,不包括max)

public static int random(int min,int max){

if(min<=max){

random random=new random();

return random.nextint(max-min)+min;

}else{

throw new illegalargumentexception("无法处理一个不合法的数字区间！");

}

}

public static void main(string[] args){

system.out.println("md5(123456):"+md5("123456"));

system.out.println("uuid:"+uuid());

system.out.println("随机数："+random(1,100));

}

}