Question

我有以下测试项目：

import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class myThreadTest {
    private static final Logger log = LoggerFactory.getLogger(myThreadTest.class);
    private ScheduledExecutorService executorService1 = Executors.newSingleThreadScheduledExecutor();
    private ScheduledExecutorService executorService2 = Executors.newSingleThreadScheduledExecutor();

    private Future<?> task1;
    private Future<?> task2;

    private class Task1 implements Runnable {

        @Override
        public synchronized void run() {
            log.debug("-----------------------");
            for (int i = 0; i < 100; i++) {
                log.debug("{} Hello from Task 1",i);
                try {
                    Thread.sleep(2);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
            log.debug("-----------------------");
        }
    }

    private class Task2 implements Runnable {

        @Override
        public synchronized void run() {
            log.debug("********************");
            for (int i = 0; i < 100; i++) {
                log.debug("{} Hello from Task 2",i);
            }
            log.debug("********************");

        }
    }

    private void start() {
        task1 = executorService1.scheduleAtFixedRate(new Task1(), 1, 500, TimeUnit.MILLISECONDS);
        task2 = executorService2.scheduleAtFixedRate(new Task2(), 1, 505, TimeUnit.MILLISECONDS);
    }

    public void stop() throws InterruptedException {

        if (task1 != null) {
            task1.cancel(false);
        }

        if (task2 != null) {
            task2.cancel(false);
        }
    }

    public static void main(String[] args) {
        myThreadTest mtt = new myThreadTest();
        mtt.start();
    }
}

我有2个任务在不同的线程中运行。然而，run方法是同步的，我可以在调试日志中看到线程在执行方法时正在发生变化 - 为什么会这样？

...
17:56:09,593 pool-2-thread-1 DEBUG myThreadTest:39 - ********************
17:56:09,593 pool-1-thread-1 DEBUG myThreadTest:21 - -----------------------
17:56:09,600 pool-2-thread-1 DEBUG myThreadTest:41 - 0 Hello from Task 2
17:56:09,600 pool-2-thread-1 DEBUG myThreadTest:41 - 1 Hello from Task 2
17:56:09,600 pool-1-thread-1 DEBUG myThreadTest:23 - 0 Hello from Task 1
17:56:09,600 pool-2-thread-1 DEBUG myThreadTest:41 - 2 Hello from Task 2
17:56:09,600 pool-2-thread-1 DEBUG myThreadTest:41 - 3 Hello from Task 2
17:56:09,601 pool-2-thread-1 DEBUG myThreadTest:41 - 4 Hello from Task 2
17:56:09,601 pool-2-thread-1 DEBUG myThreadTest:41 - 5 Hello from Task 2
17:56:09,601 pool-2-thread-1 DEBUG myThreadTest:41 - 6 Hello from Task 2
17:56:09,601 pool-2-thread-1 DEBUG myThreadTest:41 - 7 Hello from Task 2
17:56:09,602 pool-2-thread-1 DEBUG myThreadTest:41 - 8 Hello from Task 2
17:56:09,602 pool-2-thread-1 DEBUG myThreadTest:41 - 9 Hello from Task 2
17:56:09,602 pool-2-thread-1 DEBUG myThreadTest:41 - 10 Hello from Task 2
17:56:09,603 pool-2-thread-1 DEBUG myThreadTest:41 - 11 Hello from Task 2
17:56:09,603 pool-1-thread-1 DEBUG myThreadTest:23 - 1 Hello from Task 1
17:56:09,603 pool-2-thread-1 DEBUG myThreadTest:41 - 12 Hello from Task 2
17:56:09,606 pool-2-thread-1 DEBUG myThreadTest:41 - 13 Hello from Task 2
17:56:09,607 pool-2-thread-1 DEBUG myThreadTest:41 - 14 Hello from Task 2
17:56:09,607 pool-2-thread-1 DEBUG myThreadTest:41 - 15 Hello from Task 2
17:56:09,607 pool-2-thread-1 DEBUG myThreadTest:41 - 16 Hello from Task 2
17:56:09,608 pool-2-thread-1 DEBUG myThreadTest:41 - 17 Hello from Task 2
17:56:09,608 pool-2-thread-1 DEBUG myThreadTest:41 - 18 Hello from Task 2
17:56:09,608 pool-2-thread-1 DEBUG myThreadTest:41 - 19 Hello from Task 2
17:56:09,608 pool-2-thread-1 DEBUG myThreadTest:41 - 20 Hello from Task 2
17:56:09,609 pool-1-thread-1 DEBUG myThreadTest:23 - 2 Hello from Task 1
17:56:09,609 pool-2-thread-1 DEBUG myThreadTest:41 - 21 Hello from Task 2
17:56:09,609 pool-2-thread-1 DEBUG myThreadTest:41 - 22 Hello from Task 2
17:56:09,609 pool-2-thread-1 DEBUG myThreadTest:41 - 23 Hello from Task 2
17:56:09,610 pool-2-thread-1 DEBUG myThreadTest:41 - 24 Hello from Task 2
17:56:09,610 pool-2-thread-1 DEBUG myThreadTest:41 - 25 Hello from Task 2
17:56:09,610 pool-2-thread-1 DEBUG myThreadTest:41 - 26 Hello from Task 2
17:56:09,611 pool-2-thread-1 DEBUG myThreadTest:41 - 27 Hello from Task 2
17:56:09,611 pool-2-thread-1 DEBUG myThreadTest:41 - 28 Hello from Task 2
17:56:09,611 pool-2-thread-1 DEBUG myThreadTest:41 - 29 Hello from Task 2
17:56:09,611 pool-2-thread-1 DEBUG myThreadTest:41 - 30 Hello from Task 2
17:56:09,611 pool-1-thread-1 DEBUG myThreadTest:23 - 3 Hello from Task 1
17:56:09,612 pool-2-thread-1 DEBUG myThreadTest:41 - 31 Hello from Task 2
17:56:09,612 pool-2-thread-1 DEBUG myThreadTest:41 - 32 Hello from Task 2
17:56:09,612 pool-2-thread-1 DEBUG myThreadTest:41 - 33 Hello from Task 2
...

Answer 1

新的Task1（）和新的Task2（）都是不同的对象。行为符合预期。

同步ScheduledExecutorService触发的线程

1 个答案: