多线程顺序打印ABC

左手的ㄟ右手 2021-11-26 10:24 312阅读 0赞

多线程顺序打印ABC

不断唤醒机制，借用重入锁和条件队列

package com.hnist.lzn.Java8;
    
    import java.util.concurrent.locks.Condition;
    import java.util.concurrent.locks.Lock;
    import java.util.concurrent.locks.ReentrantLock;
    
    /*
    多线程顺序打印ABC
    
     */
    //
    public class PrintABC {
    
        int count = 0;
    
        Lock lock = new ReentrantLock();
    
        Condition conditionA = this.lock.newCondition();
        Condition conditionB = this.lock.newCondition();
        Condition conditionC = this.lock.newCondition();
    
        public class PrintA implements  Runnable{
    
    
            @Override
            public void run() {
                while(true){
    
                        System.out.println("--A---"+count);
                        lock.lock();
                        System.out.println("A");
    
    
                        try {
                            conditionB.signal();
                            conditionA.await();
                        } catch (InterruptedException e) {
                            e.printStackTrace();
                        }finally {
                            lock.unlock();
                        }
    
    
                    }
    
    
    
            }
        }
    
        public class PrintB implements  Runnable{
    
    
            @Override
            public void run() {
                while(true){
    
                        System.out.println("--B---"+count);
                        lock.lock();
                        System.out.println("B");
    
    
                        try {
                            conditionC.signal();
                            conditionB.await();
                        } catch (InterruptedException e) {
                            e.printStackTrace();
                        }finally {
                            lock.unlock();
                        }
    
    
    
    
    
                }
            }
        }
    
    
        public class PrintC implements  Runnable{
    
    
            @Override
            public void run() {
                while(true){
                    //if(count<10){
                        System.out.println("--C---"+count);
                        lock.lock();
                        System.out.println("C");
    
    
                        try {
                            conditionA.signal();
                            conditionC.await();
                        } catch (InterruptedException e) {
                            e.printStackTrace();
                        }finally {
                            lock.unlock();
                        }
    
    
    
    
    
                }
            }
        }
    
        public static void main(String[] args) {
    
    
            PrintABC printABC=new PrintABC();
            new Thread(printABC.new PrintA()).start();
            new Thread(printABC.new PrintB()).start();
            new Thread(printABC.new PrintC()).start();
        }
    
    
    
    }

结论： 1.重入锁配合条件队列，每个条件队列的条件不一样。同时，每个条件都被锁住了。