Lock锁 实现生产者和消费者问题

商品类：

package com.thread.lock;import java.util.concurrent.locks.Condition;import java.util.concurrent.locks.Lock;import java.util.concurrent.locks.ReentrantLock;/*Lock  Condition *noctiyAll() 唤醒所有线程 其中 唤醒自己一方的线程没有意义  唤醒全部线程又太浪费资源  *只唤醒 对方线程是最好的选择  那么如何仅唤醒对方的线程？ * JDK1.5的锁机制 * */public class Good {private String name;private int count = 0;private boolean flag = false;// 没有商品// Lock 替代了同步机制// 定义一个锁Lock lock = new ReentrantLock();// Condition Condition 将 Object 监视器方法（wait、notify 和// notifyAll）分解成截然不同的对象，以便通过将这些对象与任意 Lock 实现组合使用// 返回一个Condition 对象Condition prc = lock.newCondition();//生产派Condition cus = lock.newCondition();//消费派public void set(String name) {// 进来上锁lock.lock();while (flag) {// 有商品 一次不成立 上来就生产try {// 生产者 conditionprc.await();// Thread.sleep(1000);} catch (InterruptedException e) {// TODO Auto-generated catch blocke.printStackTrace();}}this.name = name + "..." + (count++);System.out.println(Thread.currentThread().getName() + "-----生产了-----"+ this.name);flag = true;// 唤醒的是消费者 唤醒一个 signalcus.signal();// 出同步之前解锁lock.unlock();}public void get() {lock.lock();while (!flag) {// 没有商品 第一次上来就等待try {cus.await();// Thread.sleep(50);} catch (InterruptedException e) {// TODO Auto-generated catch blocke.printStackTrace();}}System.out.println(Thread.currentThread().getName() + "====消费了====="+ this.name);flag = false;prc.signal();lock.unlock();}}

生产者：

package com.thread.lock;public class Procuder implements Runnable {private Good good;public Procuder(Good good) {super();this.good = good;}@Overridepublic void run() {while (true) {good.set("商品");}}}

消费者：

package com.thread.lock;public class Customer implements Runnable {private Good good;public Customer(Good good) {super();this.good = good;}@Overridepublic void run() {while (true) {good.get();}}}

测试类：

package com.thread.lock;public class Test {public static void main(String[] args) {Good good = new Good();Procuder p = new Procuder(good);Customer c = new Customer(good);Thread t1 = new Thread(p);Thread t2 = new Thread(c);Thread t3 = new Thread(p);Thread t4 = new Thread(c);t1.start();t2.start();t3.start();t4.start();}}