创建多线程的方式

创建多线程有三种方式来创建：
1.继承Thread类
2.实现Runnable接口
3.使用Executor框架来创建线程池

一.继承Thread类

package com.test;

/**
 * Created by admin on 2017/6/5 10:16.
 *
 */
public class DemoThread extends Thread {
    private String name;

    DemoThread(String name) {
        this.name = name;
    }

    @Override
    public void run() {
        for (int i = 0; i < 40; i++) {
            System.out.println(name + ":" + i);
        }
    }

    public static void main(String[] args) {
        new DemoThread("线程1").start();
        new DemoThread("线程2").start();
        new DemoThread("线程3").start();
    }
}

二.实现Runnable接口

package com.test;

/**
 * Created by admin on 2017/6/5 10:16.
 */
public class DemoThread implements Runnable {

    @Override
    public void run() {
        for (int i = 0; i < 40; i++) {
            System.out.println(Thread.currentThread().getName() + ":" + i);
        }
    }

    public static void main(String[] args) {
        DemoThread d1 = new DemoThread();
        Thread t1 = new Thread(d1, "线程1");
        Thread t2 = new Thread(d1, "线程2");
        Thread t3 = new Thread(d1, "线程3");
        t1.start();
        t2.start();
        t3.start();
    }
}

 三.使用线程池创建

package com.test;

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

/**
 * Created by admin on 2017/6/5 10:16.
 */
public class DemoThread {
    public static void main(String[] args) {
        //固定大小的线程池,如果线程数量大于固定值,多的线程则会等待
        ExecutorService pool = Executors.newFixedThreadPool(3);
        pool.execute(() -> {
            for (int i = 0; i < 40; i++) {
                System.out.println("线程1:" + i);
            }
        });
        pool.execute(() -> {
            for (int i = 0; i < 40; i++) {
                System.out.println("线程2:" + i);
            }
        });
        pool.execute(() -> {
            for (int i = 0; i < 40; i++) {
                System.out.println("线程3:" + i);
            }
        });
    }

}