线程通信的几种方式-蒲公英云

线程通信的几种方式

男娘i 2022-05-17 03:47 438阅读 0赞

1.第一种方式是常见的我们叫它等待唤醒方式吧

public class TestThreadCommunicate {
    public static void main(String[] args) {
        Communicate communicate = new Communicate();
        new Thread(new Runnable() {
            @Override
            public void run(){
                for (int i = 1; i <= 50; i++) {
                    communicate.sub();
                }
            }
        }).start();
        for (int i = 1; i <= 10; i++) {
            communicate.main();
        }
    }
}
class Communicate{
    private boolean bool = true;
    public synchronized void sub() {
        while (!bool) {
            try {
                // 满足条件那么就等待，所以先不满足条件,等执行完后让子线程等待，主线程执行
                this.wait();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
        for (int j = 1; j <= 10; j++) {
            System.out.println("childThread......");
        }
        bool = false;
        // 这个唤醒的是下一个线程
        this.notify();
    }
    public synchronized void main() {
        while (bool) {
            try {
                // 当执行完成后让主线程等，子线程执行
                this.wait();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
        for (int j = 1; j <= 50; j++) {
            System.out.println("mainThread......");
        }
        bool = true;
        this.notify();
    }
}

代码执行过程：先让子线程执行，让主线程等待，等子线程执行完，让主线程执行，子线程等待。

2.使用Condition的方式

public class Condition {
    public static void main(String[] args) {
        Communicate communicate = new Communicate();
        new Thread(new Runnable() {
            @Override
            public void run(){
                for (int i = 1; i <= 50; i++) {
                    communicate.sub();
                }
            }
        }).start();
        for (int i = 1; i <= 10; i++) {
            communicate.main();
        }
    }
  static class Communicate{
        private boolean bool = true;
        Lock lock = new ReentrantLock();
        java.util.concurrent.locks.Condition condition = lock.newCondition();
        public void sub() {
            lock.lock();
            try {
                while (!bool) {
                    try {
                        // 满足条件那么就等待，所以先不满足条件,等执行完后让子线程等待，主线程执行
                        condition.await();
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                }
                for (int j = 1; j <= 10; j++) {
                    System.out.println("childThread......");
                }
                bool = false;
                condition.signal();
            }finally {
                lock.unlock();
            }
        }
        public void main() {
            lock.lock();
            try {
                while (bool) {
                    try {
                        // 当执行完成后让主线程等，子线程执行
                        condition.await();
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                }
                for (int j = 1; j <= 50; j++) {
                    System.out.println("mainThread......");
                }
                bool = true;
                condition.signal();
            }finally {
                lock.unlock();
            }
            // this.notify();
        }
    }
}