我需要停止线程吗？

Question

I'm trying to implement a separate Thread in my project. Every hour a scheduler starts a thread to get files from a server and store them in my database.

My code works as it should. Since the scheduler starts a new Thread every hour, I don't know if I need to stop the Thread manually or not?

 try {
        Runnable task = new MyClass();
        Thread thread = new Thread(task);
        thread.start();

 } catch (Exception ex) {
        System.err.println("Exception-Thread: " + ex.getMessage());
 }

My Class (runnable)

  public class MyClass implements Runnable {
        @Override
        public void run() {

            try {
                //Do stuff...
            } catch (Exception ex) {
                System.out.println(ex.getMessage());
            }
        }
    }

Answer 1

如果在Runnable没有永久循环或类似的东西，那么你不需要。

Answer 2

As long as the thread has not chance of doing infinite loop Such as using while loop. Thread will stop once all the tasks in Runnable are done.

Answer 3

No, you don't need to stop the Thread manually. More than that the stop() method of thread is @deprecated and not safe:

This method is inherently unsafe. Stopping a thread with Thread.stop causes it to unlock all of the monitors that it has locked

Thread will finish its job when it will escape run block. More than that you need do to some effort to keep it running.

You need to start looking into Executors framework and not operate Threads directly.

Answer 4

Thread life cycle has following states

New, Runnable, waiting, Timed waiting, Terminated,

the first thing you should not stop your thread directly as it can cause shared variable in an inconsistent state, and if you want to then you have to make a proper flow to terminate the thread.

To take your thread in a terminate state you have to see if it is not in waiting, timed waiting or worse case in the active state depends how you have handled it.

If you are not doing any of this then need not to otherwise please make a proper method to terminate the thread.