生產者消費者ReentrantLock 版本

package com.example.demo.test;

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

public class Test1 {

    private volatile int count = 0;
    private ReentrantLock reentrantLock = new ReentrantLock();
    private Condition condition = reentrantLock.newCondition();

    public void increament(){
        try {
            reentrantLock.lock();
            // 這個用while不用if 防止虛假喚醒
            while (count != 0){
                condition.await();
            }
            count++;
            System.out.println("生產");
            condition.signalAll();
        }catch (Exception e){
            e.printStackTrace();
        }finally {
            reentrantLock.unlock();
        }
    }

    public void decreament(){
        try {
            reentrantLock.lock();
            // 這個用while不用if 防止虛假喚醒
            while (count == 0){
                condition.await();
            }
            count--;
            System.out.println("消費");
            condition.signalAll();
        }catch (Exception e){
            e.printStackTrace();
        }finally {
            reentrantLock.unlock();
        }
    }

    public static void main(String[] args) throws Exception{
        Test1 t  = new Test1();
        for (int i=0;i<5;i++){
            new Thread(()->{
                t.increament();
            },"").start();
        }
        TimeUnit.SECONDS.sleep(1);
        for (int i=0;i<5;i++){
            new Thread(()->{
                t.decreament();
            },"").start();
        }
    }
}