Java进阶知识查漏补缺06

Java线程通信之1-100交替打印

package com.cjf.Communication;

import static java.lang.Thread.sleep;

/**
 * Created with IntelliJ IDEA.
 * Description:
 * Author: Everything
 * Date: 2020-07-01
 * Time: 22:00
 */

//          1-100交替打印
//涉及到的三个方法:
//        wait():一旦执行此方法，当前线程就进入阻塞状态，并释放同步监视器。
//        notify():一旦执行此方法，就会唤醒被wait的一个线程。 如果有多个线程被wait,就唤醒优先级高的
//        notifyAll():一旦执行此方法，就会唤醒所有被wait的线程。

//    说明:
//            1. wait(), notify(), notifyALl()三个方法必须使用在同步代码块或同步方法中。
//            2. wait(), notify(), notifyAll()三个方法的调用者必须是同步代码块或同步方法中的同步监视器
//               否则，会出现ILlegaLMonitorStateException异常
//            3. wait(), notify(), notifyAll()三个方法是定义在java.Lang.object类中。


class Number implements Runnable{
    private int number = 1 ;
    @Override
    public void run() {
        while (true){
            synchronized (this) {
                notifyAll();
                if (number <= 100) {
                    try {
                        sleep(10);
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                    System.out.println(Thread.currentThread().getName()+ "打印:" + number);
                    number++;
                    try {
                        //wait方法会使调用他的对象线程阻塞
                        //waits会释放锁
                        wait();
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                }else {
                    break;
                }
            }
        }
    }
}

public class CoTest {
    public static void main(String[] args) {
        Number number = new Number();
        Thread thread1 = new Thread(number);
        Thread thread2 = new Thread(number);
        thread1.setName("Printer1");
        thread2.setName("Printer2");
        thread1.start();
        thread2.start();
    }
}

Java线程通信之经典生产者消费者问题

package com.cjf.Communication;

import java.security.PublicKey;

/**
 * Created with IntelliJ IDEA.
 * Description:
 * Author: Everything
 * Date: 2020-07-01
 * Time: 23:01
 */

//      经典生产者消费者问题

    //共用一个职员类
class Clerk{
    private int apple = 0;
    public synchronized void produceProduct(){//生产产品
        if (apple < 20){//监视器是Clerk
            apple++;
            System.out.println(Thread.currentThread().getName()+"开始生产第"+apple+"苹果");
            this.notify();
        }else {
            try {
                this.wait();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }

    public synchronized void consumerProduct() {//消费产品
        if (apple > 0){//监视器也是Clerk，这样两个线程就共用了一个监视器
            System.out.println(Thread.currentThread().getName()+"开始消费第"+apple+"苹果");
            apple--;
            this.notify();
        }else {
            try {
                this.wait();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }
}

class Producer extends Thread{
    private Clerk clerk;

    public Producer(Clerk clerk) {
        this.clerk = clerk;
    }

    @Override
    public synchronized void run() {
        System.out.println(Thread.currentThread().getName()+"开始生产产品...");
        while (true){
            try {
                Thread.sleep(10);
                clerk.produceProduct();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }
}
class Consumer extends Thread{
    private Clerk clerk;

    public Consumer(Clerk clerk) {
        this.clerk = clerk;
    }

    @Override
    public void run() {
        System.out.println(Thread.currentThread().getName()+"开始消费产品...");
        while (true){
            try {
                Thread.sleep(100);
                clerk.consumerProduct();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }
}
public class ProdAndCust {
    public static void main(String[] args) {
        Clerk clerk = new Clerk();
        Producer producer = new Producer(clerk);
        Consumer consumer = new Consumer(clerk);
        producer.setName("生产者");
        consumer.setName("消费者");
        producer.start();
        consumer.start();
    }
}