线程通信的几种方式

男娘i 2022-05-17 03:47 226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();
            }
        }
    
    }

这个是加锁机制，访问之前加锁，就如同第一个方式的wait。

当然还有其它的方式，自己看吧