On Oct 1, 2012, at 3:59 AM, Sergey Beryozkin <sberyozkin_at_talend.com> wrote:
> On 28/09/12 19:15, Marek Potociar wrote:
>>
>> On Sep 27, 2012, at 5:56 AM, Sergey Beryozkin<sberyozkin_at_talend.com> wrote:
>>
>>> Hi,
>>>
>>> I can see AsyncResponse.resume throws IllegalStateException if the invocation has not been suspended.
>>
>> I was thinking of updating the API earlier to return boolean success value instead of throwing exceptions from resume/cancel methods and forgot to make the change. That's more user-friendly than throwing an exception.
>>>
>>> IMHO it is too much of a restriction, possibly an implementation specific one.
>>
>> When you inject the AsyncResponse it is formally suspended. So the first invocation of resume() is always ok (unless the async response has been cancelled already).
>> The exception thus may only be expected in cases when someone else already resumed or cancelled the response earlier. I don't see anything implementation specific about that. I could however agree that returning boolean instead of throwing an exception may be more user-friendly.
>
> Regarding returning boolean vs throwing an exception.
> I think it does not make a difference.
>
> This is because the runtime effectively guarantees that the application level code (original resource method accepting AsyncResponse or TimeoutHandler) does always see a 'suspended' AsyncResponse.
The above would require an extra synchronization in the framework, which is not what we want IMO.
>
> However, after saying the above, I guess returning 'boolean' and updating the docs to simply say that say "resume(...) -> Resumes the suspended invocation, timeout(...) -> extends the suspended invocation, cancel(...) - cancels the suspended invocation" would probably be the right thing to do
Ok, so I guess even if we're coming from different directions, we're arriving to the same conclusion.
Marek
>
> Sergey
>
>
>>>
>>> IMHO, the following should work
>>>
>>> @GET
>>> void getIt(AsyncResponse response) {
>>> response.resume(myObject);
>>> }
>>
>> IMHO, the above should not work, unless you use @Suspended annotation. Because since JAX-RS 1.0, the first non-anotated parameter in a resource method is a request entity. AsyncResponse is not a request entity.
>>
>> If one uses the @Suspended annotation, then the example should work. Because, at least formally, the AsyncResponse has been suspended. What optimizations you do in your implementation is, of course up, to you.
>>
>>>
>>> if 'myObject' happens to be available immediately.
>>> The runtime has to suspend only after "getIt" returns, but only if no response object is already available.
>>
>> Now this is an implementation detail IMO. :)
>>
>> Marek
>>
>>
>>>
>>> Thoughts ?
>>>
>>> Sergey
>>
>
>