Can you abort BufferedReader.readLine () with Future.cancel (true)?

Question

Say I started a topic and I have something like this:

...//initiate all the socket connection future = executor.submit ( new Runnable() { public void run() { ... ... while ((str = in.readLine()) != null) { //do something here } } ); 

executor is an ExecutorService object and is a BufferedReader object

I know that you can close a socket from another thread to interrupt this thread. But when I try to use the future.cancel (true) method, although it returns true, the thread seems to be still running, does anyone know why? or in.readLine () cannot be interrupted this way?

Answer 1

Can you abort BufferedReader.readLine () with Future.cancel (true)?

All future.cancel(true) makes a call to thread.interrupt() in the associated thread. This will trigger sleep() and wait() to throw an InterruptedException and break some special NIO channels .

But the chances are that your BufferedReader will not be interrupted, as it will most likely be read from a "normal" socket or file. As you say closing a base socket from another thread is the best way to kill such an I / O method.

Answer 2

You can close the In stream to raise an IOException. Otherwise, readLine () may be locked forever.

I reviewed using JavaLangAccess.blockedOn (), but it looks pretty low.

Answer 3

readLine does not throw an InterruptedException , so it will not be affected if the thread in which it starts is interrupted. You need to explicitly check the interrupted thread status:

  while ((str = in.readLine()) != null) { if (Thread.interrupted()) { //You can deal with the interruption here } } 

But if it blocks readLine execution, the only way to abort it is to close the underlying thread that will throw an IOException.