08-Lock版的生产者消费者问题

JUC版的生产者和消费者问题

其中的await() 方法属于 condition

通过Lock可以找到Condition

代码实现：

package com.hkx.pc;

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

/**
 * @program: juc
 * @description: JUC版的生产者和消费者问题
 * @author: Casey Hu
 * @create: 2022-08-07 21:41
 **/

public class B {
    
    
    public static void main(String[] args) {
    
    
        Data2 data = new Data2();
            new Thread(()->{
    
    
                for (int i=0;i<10;i++){
    
    
                    try {
    
    
                        data.increment();
                    } catch (InterruptedException e) {
    
    
                        throw new RuntimeException(e);
                    }
                }
            },"A").start();
            new Thread(()->{
    
    
                for (int i=0;i<10;i++){
    
    
                    try {
    
    
                        data.decrement();
                    } catch (InterruptedException e) {
    
    
                        throw new RuntimeException(e);
                    }
                }
            },"B").start();
            new Thread(()->{
    
    
                for (int i=0;i<10;i++){
    
    
                    try {
    
    
                        data.increment();
                    } catch (InterruptedException e) {
    
    
                        throw new RuntimeException(e);
                    }
                }
            },"C").start();
            new Thread(()->{
    
    
                for (int i=0;i<10;i++){
    
    
                    try {
    
    
                        data.decrement();
                    } catch (InterruptedException e) {
    
    
                        throw new RuntimeException(e);
                    }
                }
            },"D").start();
        }
    }
class Data2{
    
    
    private int number=0;

    Lock lock=new ReentrantLock();
    Condition condition = lock.newCondition();
//        condition.await();   //等待
//        condition.signalAll(); //唤醒全部
    //加一操作
    public  void increment() throws InterruptedException {
    
    
        try {
    
    
            lock.lock();
            //业务代码
            while (number!=0){
    
    
                condition.await(); //等待操作
            }
            number++;
            System.out.println(Thread.currentThread().getName()+"=>"+number);
            //通知其他线程，完成了加一操作
            condition.signalAll();
        } catch (Exception e) {
    
    
            throw new RuntimeException(e);
        } finally {
    
    
            lock.unlock();
        }
    }
    //减一操作
    public  void decrement() throws InterruptedException {
    
    
        try {
    
    
            lock.lock();
            while (number==0){
    
    
                condition.await();
            }
            number--;
            System.out.println(Thread.currentThread().getName()+"=>"+number);
            //通知其他线程，完成了减一操作
            condition.signalAll();
        } catch (Exception e) {
    
    
            throw new RuntimeException(e);
        } finally {
    
    
            lock.unlock();
        }

    }
}

任何新技术的创新，绝对不是仅仅只是覆盖了原来的技术，优势和补充

Condition 精准的通知和唤醒线程

接下来，要进行有序执行A B C D 的唤醒