java线程同步经典——生产者消费者

/* * 生产者消费者问题，生产完之后要wait * 消费完之后要wait，没消费或生产一个就notify别的线程 * Object 的wait方法，指的是当前的正在访问本对象的线程wait， * wait方法只有锁定了线程才有资格wait，wait之后不再拥有锁，醒过来再去找锁 * notify叫醒一个当前对象上正在wait的线程 * 在双核笔记本上看的效果比较显著，，不用再添加sleep语句 */public class TestProducerConsumer {public static void main(String[] args) {SyncStack ss = new SyncStack();Producer pd = new Producer(ss);Consumer cs = new Consumer(ss);Thread t1 = new Thread(pd);Thread t2 = new Thread(cs);t1.start();t2.start();}}class WoTou {int id;WoTou(int id) {this.id = id;}@Overridepublic String toString() {return "WoTou" + id;}}class SyncStack {int index = 0;WoTou[] WTArr = new WoTou[6];public synchronized void push(WoTou wt) {while(index == WTArr.length) {try {this.wait();} catch (InterruptedException e) {e.printStackTrace();}}this.notify();WTArr[index] = wt;index++;}public synchronized WoTou pop() {while(index == 0) {try {this.wait();} catch (InterruptedException e) {e.printStackTrace();}}this.notify();index--;return WTArr[index];}}class Producer implements Runnable {SyncStack ss = null;Producer(SyncStack ss) {this.ss = ss;}@Overridepublic void run() {for (int i = 0; i < 20; i++) {WoTou wt = new WoTou(i);ss.push(wt);System.out.println("生产了"  + wt);//sleep，给消费者时间消费}}}class Consumer implements Runnable {SyncStack ss = null;Consumer(SyncStack ss) {this.ss = ss;}@Overridepublic void run() {for (int i = 0; i < 20; i++) {WoTou wt = ss.pop();System.out.println("消费了"  + wt);//sleep，给生产者时间生产}}}