Condition实现精准通知唤醒

package com.han.demo01;
import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;

public class TestCondition {
          
   
    public static void main(String[] args) {
          
   
        Data02 data = new Data02();
        new Thread(() -> {
          
   
            for (int i = 0; i < 10; i++) {
          
   
                data.printA();
            }
        }, "A").start();
        new Thread(() -> {
          
   
            for (int i = 0; i < 10; i++) {
          
   
                data.printB();
            }
        }, "B").start();
        new Thread(() -> {
          
   
            for (int i = 0; i < 10; i++) {
          
   
                data.printC();
            }
        }, "B").start();
    }
}

class Data02 {
          
   
    private Lock lock = new ReentrantLock();
    //给每个线程一个监视器
    Condition conditionA = lock.newCondition();
    Condition conditionB = lock.newCondition();
    Condition conditionC = lock.newCondition();
    private int num = 1;

    public void printA() {
          
   
        lock.lock();
        try {
          
   
            while (num != 1) {
          
   
                conditionA.await();
            }
            System.out.println(Thread.currentThread().getName() + "=====>AAA");
            num = 2;
            conditionB.signal();
        } catch (InterruptedException e) {
          
   
            e.printStackTrace();
        } finally {
          
   
            lock.unlock();
        }
    }

    public void printB() {
          
   
        lock.lock();
        try {
          
   
            while (num != 2) {
          
   
                conditionB.await();
            }
            System.out.println(Thread.currentThread().getName() + "=====>BBB");
            num = 3;
            conditionC.signal();
        } catch (InterruptedException e) {
          
   
            e.printStackTrace();
        } finally {
          
   
            lock.unlock();
        }
    }

    public void printC() {
          
   
        lock.lock();
        try {
          
   
            while (num != 3) {
          
   
                conditionC.await();
            }
            System.out.println(Thread.currentThread().getName() + "=====>ccc");
            num = 1;
            conditionA.signal();
        } catch (InterruptedException e) {
          
   
            e.printStackTrace();
        } finally {
          
   
            lock.unlock();
        }
    }
}