Java学习：同步问题之生产者与消费者的问题

Posted 2020-09-29 xcxfury

生产者生产馒头，消费者消费馒头。一个篮子，生产者往篮子中放馒头，消费者从篮子中取馒头。

/**
 * 这是一个篮子类
 *
 * @author xcx
 * @time 2017年7月21日上午10:01:32
 */
public class Basket {
    // 篮子里最多可以装10个馒头
    private final int Max_Numbers_StreamedBread = 10;
    SteamedBread[] sbBreads = new SteamedBread[Max_Numbers_StreamedBread];
    // 用来标记篮子中馒头的数量
    private int index = 0;

    // 向篮子中放馒头的方法
    public synchronized void push(SteamedBread sbBread) {
        while (index >= Max_Numbers_StreamedBread) {
            try {
                this.wait();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
        this.notify();
        sbBreads[index] = sbBread;
        index++;

    }

    // 从篮子中拿馒头的方法
    public synchronized SteamedBread pop() {
        while (index <= 0) {
            try {
                this.wait();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            return null;
        }
        this.notify();
        index--;
        return sbBreads[index];

    }

}

/**
 *消费者类
 *@author xcx 
 *@time 2017年7月21日上午10:23:53
 */
public class Consumer implements Runnable {
    Basket b = new Basket();
    private SteamedBread steamedBread;
    public Consumer(Basket b){
        this.b = b;        
    }

    @Override
    public void run() {
        for(int i=0;i<20;i++){
            steamedBread = b.pop();
            try {
                Thread.sleep(1000);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            if(steamedBread == null){
            }else{
                System.out.println("消费"+steamedBread);
            }
            
        }
            
        
    }

}

/**
 * 这是一个生产者类
 *
 * @author xcx
 * @time 2017年7月21日上午10:16:25
 */
public class Producer implements Runnable {
    private Basket b = new Basket();
    public Producer(Basket b){
        this.b = b;
    }
    @Override
    public void run() {
        for(int i=0;i<20;i++){
            SteamedBread sBread = new SteamedBread(i);
            try {
                Thread.sleep(1000);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            System.out.println("生产了第"+i+"个馒头");
            b.push(sBread);
        }    
    }
}

/**
 *this is a class about SteamedBread
 *@author xcx 
 *@time 2017年7月21日上午9:59:16
 */
public class SteamedBread {
    private int i;
    public SteamedBread(int i){
        this.i = i;
    }
    
    @Override
    public String toString() {
        return "第"+i+"个馒头";
    }

}

/**
 *同步线程测试类
 *@author xcx 
 *@time 2017年7月21日上午10:44:10
 */
public class Test {

    public static void main(String[] args) {
        //创建篮子的对象
        Basket basket = new Basket();
        //创建生产者线程和消费者线程
        Producer producer = new Producer(basket);
        Consumer consumer = new Consumer(basket);
        
        Thread t1 = new Thread(producer);
        Thread t2 = new Thread(consumer);
        
        t1.start();
        t2.start();
        

    }

}