package com.expgiga.JUC;import java.util.concurrent.locks.Condition;import java.util.concurrent.locks.Lock;import java.util.concurrent.locks.ReentrantLock;/** * 生產者消費者案例 */public class TestProductorAndConsumerForLock {  public static void main(String[] args) {    Clerk clerk = new Clerk();    Productor productor = new Productor(clerk);    Consumer consumer = new Consumer(clerk);    new Thread(productor, "生產者A").start();    new Thread(consumer, "消費者B").start();    new Thread(productor, "生產者C").start();    new Thread(consumer, "消費者D").start();  }}//店員class Clerk {  private int product = 0;  private Lock lock = new ReentrantLock();  private Condition condition = lock.newCondition();  //進貨方法  public void get() {    lock.lock();    try {      while (product >= 1) { //為了避免虛假喚醒，應該總是使用在循環中        System.out.println("產品已滿！");        try {          condition.await();        } catch (InterruptedException e) {          e.printStackTrace();        }      }      System.out.println(Thread.currentThread().getName() + " : " + ++product);      condition.signalAll();    } finally {      lock.unlock();    }  }  //賣貨方法  public void sale() {    lock.lock();    try {      while (product <= 0) {        System.out.println("產品缺貨！");        try {          condition.await();        } catch (InterruptedException e) {          e.printStackTrace();        }      }      System.out.println(Thread.currentThread().getName() + " : " + --product);      condition.signalAll();    } finally {      lock.unlock();    }  }}//生產者class Productor implements Runnable {  private Clerk clerk;  public Productor(Clerk clerk) {    this.clerk = clerk;  }  @Override  public void run() {    for (int i = 0; i < 20; i++) {      try {        Thread.sleep(200);      } catch (InterruptedException e) {        e.printStackTrace();      }      clerk.get();    }  }}//消費者class Consumer implements Runnable {  private Clerk clerk;  public Consumer(Clerk clerk) {    this.clerk = clerk;  }  @Override  public void run() {    for (int i = 0; i < 20; i++) {      clerk.sale();    }  }}