ScheduledExecutorService关闭不能与bufferedReader一起使用？

Question

I am using Java 8. I have a thread need start at a specific time and end at a specific time. I am using ScheduledExecutorService to do the job:

I have two threads one name is "worker" and the other is "stopworker". The Worker class contains the actual code I need run at the specific time, the "stopworker" thread just shuts down the scheduler.

 ScheduledExecutorService scheduler = Executors.newScheduledThreadPool(2);
 scheduler.schedule(worker, startSeconds, TimeUnit.SECONDS);
 scheduler.schedule(stopWorker, endSeconds, TimeUnit.SECONDS);

My Worker class:

class Worker implements Runnable {
       @Override
       public void run() {
           try {
           // HTTP GET method to call and REST API and get Streaming
           // data back, it will keep alive as long as possible and
           // gets lots of data back
           ...
           BufferedReader reader = new BufferedReader(
                   new InputStreamReader(response.getStream()));
           // deal with the data   
           ...
           } catch (IOException e) {

           } finally {
                   reader.close();
           }
       }
}

My StopWorker class:

class StopWorker implements Runnable {
      @Override
      public void run() {
           try {
              scheduler.shutdownNow();
           } catch (Exception e) {
              e.printStackTrace();
           }
      }
}

My code can start at the time I want, however, it's not shutdown correctly. I have fiddle this code a little bit and found this is because the BufferedReader class I used.

If I replaced the "worker" thread into a simple thread sleep statement and my "stopworker" works! That's why I think I/O part might block my shutdown.

The only way I shutdown the thread is by making my BufferedReader variable global and close it manually in StopWorker class. However, the code will be ugly and an IOException will be throw in the code.

My guessing is the shutdownNow function is still waiting the I/O finish first, am I right? Is there a good way solve this elegantly? Or is there a better way to make a thread start at a specific time and end at a specific time?

Answer 1

schedule() returns a ScheduledFuture , which has a boolean cancel(boolean mayInterruptIfRunning) method. If the input stream is closable by thread interruption then just call it with true.

If the stream is not interruptible then you need to close it explicitly.

Answer 2

I have figure this out after reading all your suggestions. Thank for your help, especially for the8472. I have changed following: 1) Change ScheduledExecutorService to ScheduledThreadPoolExecutor. For some reasons, ScheduledFuture cancel doesn't work with ScheduledExecutorService in my code and I don't know why. 2) Manually close the BufferedReader when canceling the class.

Hope this will help someone has the similar problems.