java多线程（1）_正确使用Condition实现等待通知

ReentrantLock的基础了解

package cn.limbo.thread.ReentrantLockTest;import java.util.concurrent.locks.Lock;import java.util.concurrent.locks.ReentrantLock;/** * Created by lhh on 2017/12/15. */public class MyService {    private Lock lock = new ReentrantLock();    public void testMethod() {        lock.lock();        for (int i = 0; i < 5; i++) {            System.out.println("ThreadName= " + Thread.currentThread().getName() + (" " + (i + 1)));        }        lock.unlock();    }}class MyThread extends Thread {    private MyService myService;    public MyThread(MyService myService) {        super();        this.myService = myService;    }    @Override    public void run() {        myService.testMethod();    }}class Run {    public static void main(String[] args) {        MyService myService = new MyService();        MyThread a1 = new MyThread(myService);        MyThread a2 = new MyThread(myService);        MyThread a3 = new MyThread(myService);        MyThread a4 = new MyThread(myService);        MyThread a5 = new MyThread(myService);        a1.start();        a2.start();        a3.start();        a5.start();        a4.start();    }}

实现正确使用Condition实现等待通知

package cn.limbo.thread.MustUseMoreCondition_OK;import java.util.concurrent.locks.Condition;import java.util.concurrent.locks.Lock;import java.util.concurrent.locks.ReentrantLock;/** * <B>功能简述</B><br> * 使用多个Condition实现通知部分线程 * * @author lhh * @date 2017/12/15 下午6:40 * */public class MyService {    private Lock lock = new ReentrantLock();    private Condition conditionA = lock.newCondition();    private Condition conditionB = lock.newCondition();    public void awaitA(){        try {            lock.lock();            System.out.println(" begin awaitA 时间为 "+System.currentTimeMillis() + " ThreadName="+Thread.currentThread().getName());            conditionA.await();            System.out.println(" end awaitA 时间为 "+System.currentTimeMillis() + " ThreadName="+Thread.currentThread().getName());        } catch (InterruptedException e) {            e.printStackTrace();        } finally {            lock.unlock();        }    }    public void awaitB(){        try {            lock.lock();            System.out.println(" begin awaitB 时间为 "+System.currentTimeMillis() + " ThreadName= "+Thread.currentThread().getName());            conditionB.await();            System.out.println(" end awaitB 时间为 "+System.currentTimeMillis() + " ThreadName= "+Thread.currentThread().getName());        } catch (InterruptedException e) {            e.printStackTrace();        } finally {            lock.unlock();        }    }    public void signalAll_A(){        try {            lock.lock();            System.out.println(" signalAll_A 的时间为"+System.currentTimeMillis()+" ThreadName= "+Thread.currentThread().getName());            conditionA.signalAll();        } finally {            lock.unlock();        }    }    public void signalAll_B(){        try {            lock.lock();            System.out.println(" signalAll_B 的时间为"+System.currentTimeMillis()+" ThreadName= "+Thread.currentThread().getName());            conditionB.signalAll();        } finally {            lock.unlock();        }    }}class ThreadA extends  Thread{    private MyService service;    public ThreadA(MyService service) {        super();        this.service = service;    }    @Override    public void run() {        service.awaitA();    }}class ThreadB extends  Thread{    private MyService service;    public ThreadB(MyService service) {        super();        this.service = service;    }    @Override    public void run() {        service.awaitB();    }}class Run{    public static void main(String[] args) throws InterruptedException {        MyService myService = new MyService();        ThreadA threadA = new ThreadA(myService);        threadA.setName("A");        threadA.start();        ThreadB threadB = new ThreadB(myService);        threadB.setName("B");        threadB.start();        Thread.sleep(3000);        System.out.println("*************");        myService.signalAll_A();    }}

打印输出

    begin awaitA 时间为 1513336178272 ThreadName=A    begin awaitB 时间为 1513336178274 ThreadName= B    *************    signalAll_A 的时间为1513336181278 ThreadName= main    end awaitA 时间为 1513336181279 ThreadName=A

说明

使用ReentrantLock对象可以唤醒制定种类的线程，这是控制部分线程的方便行为