java多线程(2)-实现生产者/消费者模式

实现生产者/消费者一对一交替打印

package cn.limbo.thread.ConditionDemo;
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>
 * 实现生产者/消费者模式:一对一交替打印
 *
 * @date 2017/12/15
 */
public class MyService {
    //ReentrantLock对象的创建
    private Lock lock = new ReentrantLock();
    //newCondition 对象可以更好的实现线程的等待和唤醒
    private Condition condition = lock.newCondition();
    private boolean hasValue = false;

    public void set() {

        try {
            lock.lock();
            while (hasValue) {
                condition.await();
            }
            System.out.println(" 打印*+ ");
            hasValue = true;
            condition.signal();
        } catch (InterruptedException e) {
            e.printStackTrace();
        } finally {
            lock.unlock();
        }

    }

    public void get() {
        try {
            lock.lock();
            while (!hasValue) {
                condition.await();
            }
            System.out.println(" 打印*- ");
            hasValue = false;
            condition.signal();
        } catch (InterruptedException e) {
            e.printStackTrace();
        } finally {
            lock.unlock();
        }
    }

}

class MyThreadA extends Thread {
    private MyService myService;

    public MyThreadA(MyService myService) {
        super();
        this.myService = myService;
    }

    @Override
    public void run() {
        for (int i = 0; i < Integer.MAX_VALUE; i++) {
            myService.set();
        }
    }
}

class MyThreadB extends Thread {
    private MyService myService;

    public MyThreadB(MyService myService) {
        super();
        this.myService = myService;
    }

    @Override
    public void run() {
        for (int i = 0; i < Integer.MAX_VALUE; i++) {
            myService.get();
        }
    }
}


class Run{
    public static void main(String[] args) {
        MyService service = new MyService();
        MyThreadA myThreadA = new MyThreadA(service);
        myThreadA.start();

        MyThreadB threadB = new MyThreadB(service);
        threadB.start();

    }
}

多对多交替打印

package cn.limbo.thread.ConditionM2MDemo;

import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;

/**
 * Created by lhh on 2017/12/18.
 */
public class MyService {
    private Lock lock = new ReentrantLock();
    private Condition condition = lock.newCondition();
    private boolean hasValue = false;

    public void set() {

        try {
            lock.lock();
            while (hasValue) {
                System.out.println(" 有可能**+连续");
                condition.await();
            }
            System.out.println(" 打印*+ ");
            hasValue = true;
            condition.signal();
        } catch (InterruptedException e) {
            e.printStackTrace();
        } finally {
            lock.unlock();
        }

    }

    public void get() {
        try {
            lock.lock();
            while (!hasValue) {
                System.out.println(" 有可能**-连续");
                condition.await();
            }
            System.out.println(" 打印*- ");
            hasValue = false;
            condition.signal();
        } catch (InterruptedException e) {
            e.printStackTrace();
        } finally {
            lock.unlock();
        }
    }

}

class MyThreadA extends Thread {
    private MyService myService;

    public MyThreadA(MyService myService) {
        super();
        this.myService = myService;
    }

    @Override
    public void run() {
        for (int i = 0; i < Integer.MAX_VALUE; i++) {
            myService.set();
        }
    }
}

class MyThreadB extends Thread {
    private MyService myService;

    public MyThreadB(MyService myService) {
        super();
        this.myService = myService;
    }

    @Override
    public void run() {
        for (int i = 0; i < Integer.MAX_VALUE; i++) {
            myService.get();
        }
    }
}


class Run {
    public static void main(String[] args) {
        MyService service = new MyService();
        MyThreadA[] myThreadAs = new MyThreadA[10];
        MyThreadB[] myThreadBs = new MyThreadB[10];

        for (int i = 0; i < 10; i++) {
            myThreadAs[i] = new MyThreadA(service);
            myThreadBs[i] = new MyThreadB(service);
            myThreadAs[i].start();
            myThreadBs[i].start();
        }
    }
}

运行结果

发现程序处于假死状态,需要把MyService中的两处signal()代码改成signalAll()即可。但此时,signalAll()是唤醒所有线程那么被唤醒的很有可能是同类。

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转载自blog.csdn.net/arcprodrelhh/article/details/78831395