生產(chǎn)者消費者模式

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管程法

/**
 * 線程協(xié)作--生產(chǎn)者消費者模式（模擬麥當勞點雞）--管程法
 */
public class PCDemo {
    public static void main(String[] args) {
        SynContainer container = new SynContainer();

        new Thread(new Productor(container)).start();
        new Thread(new Consumer(container)).start();
    }
}

//生產(chǎn)者
class Productor implements Runnable{
    SynContainer container;

    public Productor(SynContainer container) {
        this.container = container;
    }

    @Override
    public void run() {
        //生產(chǎn)100只雞
        for (int i = 1; i <= 100; i++) {
            try {
                TimeUnit.MICROSECONDS.sleep(1);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            container.push(new Chicken(i));
        }
    }
}

//消費者
class Consumer implements Runnable{
    SynContainer container;

    public Consumer(SynContainer container) {
        this.container = container;
    }

    @Override
    public void run() {
        //消費100只雞
        for (int i = 1; i <= 100; i++) {
            try {
                TimeUnit.MICROSECONDS.sleep(500);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            container.pop();
        }
    }
}

//產(chǎn)品 -- 雞
class Chicken{
    int id;
    public Chicken(int id) {
        this.id = id;
    }
}

//容器
class SynContainer {
    Chicken[] chickens = new Chicken[10];
    int count;//柜臺有多少只雞

    //生產(chǎn)者生產(chǎn)雞
    public synchronized void push(Chicken chicken){
        //如果滿了，等待消費者消費
        if(count == chickens.length){
            try {
                this.wait();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }

        //沒滿，把雞放到柜臺
        chickens[count++] = chicken;
        System.out.println("生產(chǎn)了第 " + chicken.id +" 只雞，柜臺共有" + count + "只雞");

        //通知消費者消費
        this.notify();
    }

    //消費者消費雞
    public synchronized Chicken pop(){
        Chicken chicken = null;

        //如果柜臺沒有，等待生產(chǎn)者生產(chǎn)
        if(count == 0){
            try {
                this.wait();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }

        //如果有，消費
        chicken = chickens[--count];
        System.out.println("消費了第 " + chicken.id +" 只雞，柜臺共有" + count + "只雞");

        //通知生產(chǎn)者生產(chǎn)
        this.notifyAll();
        return chicken;
    }
}

信號燈法

**
 * 線程協(xié)作--生產(chǎn)者消費者模式（模擬觀眾觀看演員節(jié)目）--信號燈法
 */
public class SignalLightDemo {
    public static void main(String[] args) {
        Tv tv = new Tv();

        new Thread(new Player(tv)).start();
        new Thread(new Watcher(tv)).start();
    }
}

//生產(chǎn)者 -- 演員
class Player implements Runnable{
    private Tv tv;
    public Player(Tv tv) {
        this.tv = tv;
    }

    @Override
    public void run() {
        for (int i = 0; i < 20; i++) {
            tv.play("快樂大本營--" + i);
        }
    }
}

//消費者 -- 觀眾
class Watcher implements Runnable{
    private Tv tv;
    public Watcher(Tv tv) {
        this.tv = tv;
    }

    @Override
    public void run() {
        for (int i = 0; i < 20; i++) {
            tv.watch();
        }
    }
}

//產(chǎn)品 -- 節(jié)目
class Tv {

    private String voice;//節(jié)目內(nèi)容
    // 標志位：演員表演節(jié)目，觀眾等待 T
    //         觀眾觀看節(jié)目，演員等待 F
    private boolean flag = true;

    //演員 -- 表演節(jié)目
    public synchronized void play(String voice){
        // 觀眾在觀看節(jié)目，演員等待
        if(!flag){
            try {
                this.wait();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
        //演員表演了節(jié)目，并通知觀眾觀看
        this.voice = voice;
        this.flag = !this.flag;
        System.out.println("演員表演了:" + this.voice);
        this.notifyAll();
    }

    //觀眾 -- 觀看節(jié)目
    public synchronized void watch(){
        // 演員在表演節(jié)目，觀眾等待
        if (flag){
            try {
                this.wait();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
        // 觀眾觀看了節(jié)目，并通知演員表演
        this.flag = !this.flag;
        System.out.println("觀眾觀看了："+this.voice);
        this.notifyAll();
    }
}

線程池

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/**
 * 線程池：service.execute(Runnable);
 */
public class ExcutorDemo {
    public static void main(String[] args) {
        ExecutorService service = Executors.newFixedThreadPool(10);

        service.execute(new MyRunnable());
        service.execute(new MyRunnable());
        service.execute(new MyRunnable());
        service.execute(new MyRunnable());

        service.shutdown();
    }
}

class MyRunnable implements Runnable{
    @Override
    public void run() {
        System.out.println(Thread.currentThread().getName());
    }
}