Canceling an asynchronous IO operation throws NPE

[Umashankar]

Alan Bateman wrote:
> Umashankar wrote:
>> Hi Alan,
>> On canceling an IO operation that is in progress,I get a 
>> CancellationException which is expected as per the spec.
>> But in the stack trace, I also see a NullPointerException.
>> Following is the stack trace.
>>    java.util.concurrent.CancellationException
>>        at sun.nio.ch.PendingFuture.get(PendingFuture.java:136)
>>        at 
>> AsyncIOCancelTests.testWrite2FileChannel_01(AsyncIOCancelTests.java:50)
>>        at AsyncIOCancelTests.main(AsyncIOCancelTests.java:19)
>> Exception in thread "Thread-1" java.lang.NullPointerException
>>        at sun.nio.ch.PendingFuture$1.run(PendingFuture.java:206)
>>        at 
>> java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110) 
>>
>>        at 
>> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603) 
>>
>>        at java.lang.Thread.run(Thread.java:674)
>>
>> Please let me know if this is correct.
> There's a bug here - thanks! It arises when you cancel an I/O 
> operation that doesn't have a CompletionHandler but the code is trying 
> to invoke its cancelled method. It should be harmless (meaning an 
> annoyance printed to the console) and I'll fix it for the next build.
>
> -Alan.
>

Alan,
In my case I am specifying a CompletionHandler to the write() operation 
that I cancel immediately after initiating it.

Thanks,
Umashankar