多线程案例：生产者和消费者

1.生产和消费的产品抽象类：

public abstract class Product {

public String name;
public abstract String toString();
}

2.一个具体的产品类：

public class AProduct extends Product { public AProduct(String name) { this.name = name; // TODO Auto-generated constructor stub } public String toString() { // TODO Auto-generated method stub return this.name; } }

3.容器类（仓库）：

import java.util.ArrayList;


 /*
  * 存放生产者和消费者的产品队列
  * */
 public class Container {
       
     private ArrayList arrList = new ArrayList();
     private int LENGTH = 10;
     public boolean isFull() {
       
         return arrList.size()==LENGTH;
     }
     public boolean isEmpty() {
       
         return arrList.isEmpty();
     }
     /* 如果此处不加synchronized锁，那么也可以再调用push的地方加锁
     * 既然此处加了锁，那么再别的地方可以不加锁
     */
     public synchronized void push(Object o) {
       
         arrList.add(o);
     }
     // 如果此处不加synchronized锁，那么也可以再调用push的地方加锁
     public synchronized Object pop() {
       
         Object lastOne = arrList.get(arrList.size()- 1);
         arrList.remove(arrList.size()- 1);
         return lastOne;
     }
 }

4.休息一会，生产者和消费者都要休息，因此作为抽象基类：

public abstract class Sleep { public void haveASleep() throws InterruptedException { Thread.sleep((long)(Math.random()* 3000)); } }

/* * 消费者线程 * */ public class Consumer extends Sleep implements Runnable { private Container contain =null; public Consumer(Container contain) { this.contain = contain; } public void run() { // TODO Auto-generated method stub while(true) { synchronized(contain) { while(contain.isEmpty()) { try{ contain.wait(); }catch(InterruptedException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } consume();//消费 try { haveASleep(); }catch(InterruptedException e) { // TODO Auto-generated catch block e.printStackTrace(); } synchronized(contain) { contain.notify(); } } } private void consume() { Product a = (AProduct)contain.pop(); System.out.println("消费了一个产品"+ a.toString()); } }

/* * 生产者线程 * */ public class Producator extends Sleep implements Runnable { private Container contain = null; public Producator(Container contain) { super(); this.contain = contain; } public void run() { // TODO Auto-generated method stub while(true) { synchronized(contain) { while(contain.isFull()) { try{ contain.wait();// 阻塞当前线程,当前线程进入等待队列。这个时候只有等待别的线程来唤醒自己了。 }catch(InterruptedException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } producer();// 生产一个产品 try { haveASleep(); }catch(InterruptedException e) { // TODO Auto-generated catch block e.printStackTrace(); } synchronized(contain) { contain.notify();// 唤醒等待队列中正在等待的第一个线程，让其执行。 } } } public void producer() { Product aProduct = new AProduct("pp:"+String.valueOf((int)(10*Math.random()))); System.out.println("生产了一个产品："+ aProduct.toString()); contain.push(aProduct); } }

5. 写一个测试：

public class TestMain { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub Container contain = new Container(); Producator p = new Producator(contain); Consumer c = new Consumer(contain); Thread pt =new Thread(p); Thread ct =new Thread(c); pt.start(); ct.start(); } }