Thread线程

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package com.xiahong.base.Thread;
//创建线程方式一：1.继承Thread类  2.重写run（）方法 3.调用start 开启线程
public class ThreadTest extends Thread{
    @Override
    public void run() {
        //run方法线程体
        for (int i = 0; i < 20; i++) {
            System.out.println("我在看代码---"+i);
        }
    }
/*
*
* 总结 线程开启不一定立即执行，由cpu调度执行
* */
    public static void main(String[] args) {
        //main方法主线程i

        //创建一个线程对象
        ThreadTest threadTest =new ThreadTest();

        //调用start（）方法开启线程
        threadTest.start();

        for (int i = 0; i < 20; i++) {
            System.out.println("我在学习多线程--"+i);
        }
    }
}

package com.xiahong.base.Thread;

import org.apache.commons.io.FileUtils;

import java.io.File;
import java.io.IOException;
import java.net.URL;

//联系Thread ，实现多线程同步下载图片
public class ThreadTest1 extends Thread{
   private String url;//网络图片地址
    private String name; //保存的文件名
public  ThreadTest1(String url,String name){
    this.name=name;
    this.url=url;
}


    @Override
    public void run() {
        WebDownloader webDownloader=new WebDownloader();
        webDownloader.downloader(url,name);
        System.out.println("下载了文件名为"+name);
    }

    public static void main(String[] args) {
        ThreadTest1 threadTest1 =new ThreadTest1("https://gd1.alicdn.com/imgextra/i4/4292439402/O1CN01REmz0J2JKATKbf1j5_!!4292439402.jpg_400x400.jpg","1.jpg");
        ThreadTest1 threadTest2 =new ThreadTest1("https://gd1.alicdn.com/imgextra/i4/4292439402/O1CN01REmz0J2JKATKbf1j5_!!4292439402.jpg_400x400.jpg","2.jpg");
        ThreadTest1 threadTest3 =new ThreadTest1("https://gd1.alicdn.com/imgextra/i4/4292439402/O1CN01REmz0J2JKATKbf1j5_!!4292439402.jpg_400x400.jpg","3.jpg");
        //先下载t1
        threadTest1.start();
        //先下载t2
        threadTest2.start();
        //先下载t3
        threadTest3.start();
    }
}
//下载器
class WebDownloader{
//下载方法
    public void downloader(String url,String name){
        try {
            FileUtils.copyURLToFile(new URL(url),new File(name));
        } catch (IOException e) {
            e.printStackTrace();
            System.out.println("IO异常,downloader方法出现问题");
        }
    }


}

package com.xiahong.base.Thread;
//多个线程同时操作同一个对象
//买火车票的例子
//发现问题：多个线程操作同一个资源的情况下，线程不安全，数据紊乱
public class ThreadTest3 implements Runnable{
    //票数
    private int ticketNums=10;

    @Override
    public void run() {
while (true){
    if(ticketNums<=0){
        break;
    }
    //模拟延时
    try {
        Thread.sleep(200);
    } catch (InterruptedException e) {
        e.printStackTrace();
    }
    System.out.println(Thread.currentThread().getName()+"-->拿到了第"+ticketNums--+"张票");
}
    }

    public static void main(String[] args) {
        ThreadTest3 threadTest3 =new ThreadTest3();
        new Thread(threadTest3,"小明").start();
        new Thread(threadTest3,"老师").start();
        new Thread(threadTest3,"黄牛党").start();
    }
}

package com.xiahong.base.Thread;

//模拟龟兔赛跑
public class Race implements Runnable {
    //胜利者
    private static String winner;

    @Override
    public void run() {
        for (int i = 0; i <= 100; i++) {
            //模拟兔子休息
            if (Thread.currentThread().getName().equals("乌龟") && i % 10 == 0) {
                try {
                    Thread.sleep(1);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
            //判断比赛是否结束
            boolean flag = gameOver(i);
            if (flag) {
                break;
            }
            System.out.println(Thread.currentThread().getName() + "-->跑了" + i + "步");
        }

    }

    //判断是否完成比赛
    private boolean gameOver(int steps) {
//判断是否有胜利者
        if (winner != null) {
            return true;
        }
        {
            if (steps >= 100) {
                winner = Thread.currentThread().getName();
                System.out.println("winner is" + winner);
                return true;
            }
        }
        return false;
    }

    public static void main(String[] args) {
        Race race = new Race();
        new Thread(race, "兔子").start();
        new Thread(race, "乌龟").start();
    }
}

package com.xiahong.base.Thread;

import org.apache.commons.io.FileUtils;

import java.io.File;
import java.io.IOException;
import java.net.URL;
import java.util.concurrent.*;

/*//线程创建方式3：实现Callable接口
* Callable的好处
* 1.可以定义返回值
* 2.可以抛出异常
* */

public class TestCallable implements Callable<Boolean> {
    private String url;//网络图片地址
    private String name; //保存的文件名
    public  TestCallable(String url,String name){
        this.name=name;
        this.url=url;
    }


    @Override
    public Boolean call() {
        WebDownloader webDownloader=new WebDownloader();
        webDownloader.downloader(url,name);
        System.out.println("下载了文件名为"+name);
        return true;
    }

    public static void main(String[] args) throws ExecutionException, InterruptedException {
        TestCallable threadTest1 =new TestCallable("https://gd1.alicdn.com/imgextra/i4/4292439402/O1CN01REmz0J2JKATKbf1j5_!!4292439402.jpg_400x400.jpg","1.jpg");
        TestCallable threadTest2 =new TestCallable("https://gd1.alicdn.com/imgextra/i4/4292439402/O1CN01REmz0J2JKATKbf1j5_!!4292439402.jpg_400x400.jpg","2.jpg");
        TestCallable threadTest3 =new TestCallable("https://gd1.alicdn.com/imgextra/i4/4292439402/O1CN01REmz0J2JKATKbf1j5_!!4292439402.jpg_400x400.jpg","3.jpg");
        //创建执行服务
        ExecutorService service = Executors.newFixedThreadPool(3);
        //提交执行
        Future<Boolean> result1 =service.submit(threadTest1);
        Future<Boolean> result2 =service.submit(threadTest2);
        Future<Boolean> result3 =service.submit(threadTest3);
        //获取结果
        boolean rs1 =result1.get();
        boolean rs2 =result2.get();
        boolean rs3 =result3.get();
        //打印返回值
        System.out.println(rs1);
        System.out.println(rs2);
        System.out.println(rs3);
        //关闭服务
        service.shutdownNow();
    }
}

Thread线程

标签：public   xtend   read   总结   name   重写   tst   执行   方式   

原文地址：https://www.cnblogs.com/xiahong/p/14453548.html