java-thread

  一、java的线程挂起合唤醒

      wait  notify

 

public class Main {



    public static Object monitor = new Object();
    public static class ThreadTest1 extends Thread{

        @Override
        public void run() {
            synchronized (monitor) {
                System.err.println(
                        ThreadTest1.currentThread().getName() + "-" + System.currentTimeMillis() +
                                "begin run......"
                );

                try {
                    monitor.wait();
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }

                System.err.println(ThreadTest1.currentThread().getName() + "-" + System.currentTimeMillis() + "ater notify begin run......");
            }
        }
    }


    public static class ThreadTest2 extends Thread{

        @Override
        public void run() {
            synchronized (monitor) {
                System.err.println(
                        ThreadTest1.currentThread().getName() + "-" + System.currentTimeMillis() +
                                "begin run......"
                );

                monitor.notify();

                System.err.println(ThreadTest2.currentThread().getName() + "-" + System.currentTimeMillis() + "notify wating thread......");
            }
        }
    }

    public static void main(String[] args){
        ThreadTest1 threadTest1 = new ThreadTest1();
        ThreadTest2 threadTest2 = new ThreadTest2();

        threadTest1.start();
        threadTest2.start();

    }
}

 二、join

public static int i = 0;
    public static class ThreadTest extends Thread{

        @Override
        public void run() {
            for (;i<1000000;i++);
        }
    }

    public static void main(String[] args) throws InterruptedException {

        Thread thread = new ThreadTest();
        thread.start();
        thread.join();
        System.err.println("current i:"+i);
    }

join会阻塞当前线程，是目标线程执行完成后在通知当前线程继续执行；