java简单实现多线程及线程池实例详解
本文为大家分享了java多线程的简单实现及线程池实例，供大家参考，具体内容如下
一、多线程的两种实现方式
1、继承Thread类的多线程
/**
*继承Thread类的多线程简单实现
*/
publicclassextThreadextendsThread{
publicvoidrun(){
for(inti=0;i<100;i++){
System.out.println(getName()+"-"+i);
}
}
publicstaticvoidmain(Stringarg[]){
for(inti=0;i<100;i++){
System.out.println(Thread.currentThread().getName()+"-"+i);
if(i==50){
newextThread().start();
newextThread().start();
}
}
}
}
2、实现Runnable接口的多线程
/**
*实现runable接口的多线程实例
*/
publicclassrunThreadimplementsRunnable{
publicvoidrun(){
for(inti=0;i<100;i++){
System.out.println(Thread.currentThread().getName()+"-"+i);
}
}
publicstaticvoidmain(Stringarg[]){
for(inti=0;i<100;i++){
System.out.println(Thread.currentThread().getName()+"-"+i);
if(i==50){
runThreadrt=newrunThread();
newThread(rt,"新线程1").start();
newThread(rt,"新线程2").start();
}
}
}
}
二、线程池的简单实现
//实现Runnable接口
classTestThreadimplementsRunnable{
publicvoidrun(){
for(inti=0;i<100;i++){
System.out.println(Thread.currentThread().getName()+"i的值为："+i);
}
}
}
publicclassthreadPoolTest{
publicstaticvoidmain(String[]args){
//创建一个具有固定线程数的线程池
ExecutorServicepool=Executors.newFixedThreadPool(5);
//向线程池中提交三个线程
pool.submit(newTestThread());
pool.submit(newTestThread());
pool.submit(newTestThread());
//关闭线程池
pool.shutdown();
}
}
三、java爬虫使用线程池实例
/**
*爬虫调度线程池
*/
publicclassthreadPool{
publicstaticHashMapstatusMap=newHashMap();
//存放爬虫，key为爬虫的id，value为爬虫的线程池
staticHashMapthreadMap=newHashMap();
//创建一个线程池
staticThreadPoolExecutorthreadPool=newThreadPoolExecutor(200,230,80000L,
TimeUnit.SECONDS,
newArrayBlockingQueue(10),
newThreadPoolExecutor.CallerRunsPolicy());
publicstaticvoidexecuteThread(Spidersspider){
statusMap.put(String.valueOf(spider.getId()),spider);
//爬虫有效
if(spider.getFlag()==0){
if(spider.getStatus()==0){
//表示爬虫进入抓取状态
ThreadPoolExecutordetailPool=null;
if(threadMap.get(spider.getId())==null){
detailPool=newThreadPoolExecutor(30,80,80000L,
TimeUnit.SECONDS,newArrayBlockingQueue(
10),
newThreadPoolExecutor.CallerRunsPolicy());
threadMap.put(spider.getId(),detailPool);
threadPool.execute(newthreadRun(spider,threadMap));
}
}
}
}
}
//实现Runnable接口
classthreadRunimplementsRunnable{
privateHashMapthreadPoolMap;
privateSpidersspider;
publicthreadRun(Spidersspider,
HashMapthreadPoolMap){
this.threadPoolMap=threadPoolMap;
this.spider=spider;
}
//线程执行体
publicvoidrun(){
try{
if("rong360".equals(spider.getWebsite())){
newRongThread(threadPoolMap.get(spider.getId()),spider)
.startSpider();
}elseif("xxgg_sd".equals(spider.getWebsite())){
newSpider_ShanDong(threadPoolMap.get(spider
.getId()),spider).startSpider();
}elseif("xxgg_gz".equals(spider.getWebsite())){
newSpider_GuiZhou(threadPoolMap.get(spider
.getId()),spider).startSpider();
}elseif("sx".equals(spider.getWebsite())){
newSpiderSX(spider).startSpider();
}elseif("baidu".equals(spider.getWebsite())){
newSpiderBaiDu(spider).startSpider();
}elseif("11315".equals(spider.getWebsite())){
newSpider11315ByName(spider).startSpider();
}
}catch(Exceptione){
e.printStackTrace();
}
}
}
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持毛票票。