java多线程

java多线程基本实现方式，

一 继承Thread类，重写Thread类的run方法

二 实现Runnabel接口

1 继承Thread类

package com.hzlssd.Thread;

public class MyThread extends Thread{

public void run() { 

for (int i = 0; i < 100; i++) { 

if ((i) % 10 == 0) { 

System.out.println("-------" + i); 

} 

System.out.print(i); 

try { 

//休眠10秒

Thread.sleep(10); 

System.out.print("线程睡眠1毫秒！\n"); 

} catch (InterruptedException e) { 

e.printStackTrace(); 

} 

} 

} 

public static void main(String[] args) { 

new MyThread().start(); 

}

}

2 实现Runnable接口

public class DoSomething implements Runnable{

    private String name; 

    

    public DoSomething(String name) { 

        this.name = name; 

    }

@Override

public void run() {

for (int i = 0; i < 5; i++) { 

for (long k = 0; k < 100; k++); 

System.out.println(name + ": " + i);

}

} 

}

package com.hzlssd.Thread;

import static org.junit.Assert.*;

import org.junit.Test;

public class TestRunnable {

   @Test

   public void RunnableTest() throws InterruptedException{

DoSomething ds1 = new DoSomething("阿三"); 

        DoSomething ds2 = new DoSomething("李四"); 

        Thread t1 = new Thread(ds1); 

        Thread t2 = new Thread(ds2); 

        t1.start(); 

        t2.start();

        t2.join();

    }  

}

3项目中的应用

public void test( )  { 

Thread t = new Thread(new Runnable(){

@Override

public void run() {

SmartSocketServer.main(new String[1]);    

}

});

    t.start();

};

线程池操作

package com.hzlssd.Thread;

import java.util.concurrent.ExecutorService;

import java.util.concurrent.Executors;

public class ExecutorServiceTest {

    

public static void main(String[] args) { 

   

        //创建一个可重用固定线程数的线程池 

        //获取当前电脑cpu数

        int   cpuNum = Runtime.getRuntime().availableProcessors();

        //定义单个cpu线程池的大小

        int   POOL_SIZE = 30;

        ExecutorService pool = Executors.newFixedThreadPool(cpuNum * POOL_SIZE); 

        

        //创建实现了Runnable接口对象，Thread对象当然也实现了Runnable接口 

        Thread t1 = new MyThreadInner(); 

        Thread t2 = new MyThreadInner(); 

        Thread t3 = new MyThreadInner(); 

        Thread t4 = new MyThreadInner(); 

        Thread t5 = new MyThreadInner(); 

        

        //将线程放入池中进行执行,相当于调用了start方法 

       pool.execute(t1); 

        pool.execute(t2); 

        pool.execute(t3); 

        pool.execute(t4); 

        pool.execute(t5); 

        //关闭线程池 

        pool.shutdown(); 

    }

}

class MyThreadInner extends Thread{ 

@Override 

public void run() { 

System.out.println(Thread.currentThread().getName()+"正在执行。。。"); 

}

}

java多线程取得当前线程的名称

Thread.currentThread().getName()

赋名称

Thread.currentThread().setName()

让出cpu的执行权

Thread.currentThread().yield()

join（）在A线程中调用B线程的join（）方法，当执行到此方法时，A线程停止执行，直到

B线程停止执行，A线程才继续执行

判断当前线程是否存活

Boolean bol = thread1.isAlive()

显示得让线程睡眠

thread1.sleep(long l)

设置线程的优先级 1 - 10 数值越大，优先级越高 默认的优先级为5

tr1.setPriority(Thread.MAX_PRIRITY)

获得当前线程的优先级

th1.getPriority()