多线程之juc版

package com.lyon.juc;

import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;

/**
 * 线程之间的通讯问题：生产者与消费者问题！ 等待唤醒，通知唤醒
 * 线程交替执行 A   B  操作同一变量  num = 0
 * A num+1
 * B num-1
 */
public class B {
    public static void main(String[] args) {
        Data1 data1 = new Data1();
        new Thread(()->{
            for (int i = 0; i < 10; i++) {
                data1.increment();
            }
        },"A").start();

        new Thread(()->{
            for (int i = 0; i < 10; i++) {
                data1.decrement();
            }
        },"B").start();

        new Thread(()->{
            for (int i = 0; i < 10; i++) {
                data1.increment();
            }
        },"C").start();

        new Thread(()->{
            for (int i = 0; i < 10; i++) {
                data1.decrement();
            }
        },"D").start();
    }
}

//判断是否需要等待   业务   通知
class Data1{ //资源类

    private int num = 0;

    Lock lock = new ReentrantLock();
    Condition condition = lock.newCondition();
    //condition.await(); //睡眠
    //condition.signalAll();//唤醒全部

    //+1
    public  void increment(){
        lock.lock();
        try{
            while (num!=0){
                //等待
                condition.await();
            }
            num++;
            System.out.println(Thread.currentThread().getName()+"=>"+num);
            //通知其他线程，我+1完毕了
             condition.signalAll();
        }catch (Exception e){
            e.printStackTrace();
        }finally {
            lock.unlock();
        }

    }
    //-1
    public  void decrement(){
        lock.lock();
        try {
            while (num==0){
                //等待
                condition.await();
            }
            num--;
            System.out.println(Thread.currentThread().getName()+"=>"+num);
            //通知其他线程，我-1完毕了
            condition.signalAll();
        }catch (Exception e){
          e.printStackTrace();
        }finally {
           lock.unlock();
        }

    }
}