java生产者消费者问题（线程同步与线程等待的应用）

生产者

 

/** * 类说明：生产者 * * @author 作者: user * @version 创建时间：2011-4-5 下午01:48:11 */public class Producer implements Runnable {private SyncStack ss;private int num;private static int counter = 1;public Producer(SyncStack ss) {this.ss = ss;num = counter++;}@Overridepublic void run() {char c;for (int i = 0; i < 10; i++) {c = (char) (Math.random() * 26 + 'A');ss.push(c);//向堆栈中添加数据System.out.println("生产者 " + num + ": " + c);try {Thread.sleep((int) (Math.random() * 300));} catch (InterruptedException e) {e.printStackTrace();}}}} 

 

消费者

 

/** * 类说明：消费者 * * @author 作者: user * @version 创建时间：2011-4-5 下午01:56:18 */public class Consumer implements Runnable {private SyncStack ss;//堆栈对象private int num;private static int counter = 1;public Consumer(SyncStack ss) {this.ss = ss;num = counter++;}@Overridepublic void run() {char c;for (int i = 0; i < 10; i++) {c = ss.pop();//从堆栈中取数据System.out.println("消费者 " + num + ": " + c);try {Thread.sleep((int) (Math.random() * 200));} catch (InterruptedException e) {e.printStackTrace();}}}} 

 

堆栈类

 

import java.util.ArrayList;import java.util.List;/** * 类说明：堆栈类 * * @author 作者: user * @version 创建时间：2011-4-5 下午01:17:48 */public class SyncStack {private List<Character> buffer = new ArrayList<Character>();public SyncStack() {}// 堆栈取数据public synchronized char pop() {char c;if (buffer.size() == 0) {try {System.out.println(Thread.currentThread().getName()+ " 正在等待 ……………………");this.wait();// 如果堆栈中没有数据 则线程等待} catch (Exception e) {e.printStackTrace();}}c = ((Character) buffer.get(buffer.size() - 1)).charValue();buffer.remove(buffer.size() - 1);return c;}// 向堆栈中添加数据public synchronized void push(char c) {this.notify();// 唤醒在此对象监视器上等待的单个线程Character ch = new Character(c);buffer.add(ch);}} 

 

主方法

 

/** * 类说明： * * @author 作者: user * @version 创建时间：2011-4-5 下午01:59:54 */public class Main {/** * @param args */public static void main(String[] args) {SyncStack ss = new SyncStack();//生产者pProducer p = new Producer(ss);Thread t1 = new Thread(p);t1.start();//生产者p2Producer p2 = new Producer(ss);Thread t3 = new Thread(p2);t3.start();//消费者1Consumer c = new Consumer(ss);Thread t2 = new Thread(c);t2.setName("消费者1 ");t2.start();//消费者1Consumer c2 = new Consumer(ss);Thread t4 = new Thread(c2);t4.setName("消费者2 ");t4.start();}}