On 21/05/2014 18:49, Pavel Bucek wrote:
>
> Please provide any feedback by COB Friday - 5/30/2014. We plan to send
> this to JCP in the first week of June to start the 30 day review period
> for this MR.
1. We should deprecate the existing addMessageHandler() methods.
2. We should define and document the behaviour (throw an Exception? If
so, what type?) of the existing addMessageHandler() methods if the type
can not be determined.
The code Tomcat uses to figure out the correct type for these methods
makes my head hurt every time I have to work on it. I'd love to be able
to throw that code away but that means making the existing
addMessageHandler() methods NO-OPs or having them throw an exception -
neither of which is good for backward compatibility.
Mark
>
> Thanks,
> Pavel
>
> On 21/05/14 11:22, Pavel Bucek wrote:
>> Hi all,
>>
>> as you might have noticed, I filed blocker bug against WEBSOCKET_SPEC
>> project - [1].
>>
>> The main issue is that current Session.addMessageHandler method cannot
>> handle message handlers in form of lambda expressions, because there
>> is no information about its generic type parameter available. We
>> discussed this issue with Brian Goetz and he pointed out that current
>> API is wrong not only for this case, but also for more complicated
>> generics usages and is reliable only for anonymous classes created
>> directly from MessageHandler.Whole and MessageHandler.Partial (type
>> information is in the generated class file), so the issue itself is
>> not limited only to Java SE 8.
>>
>> We think that this issue is important enough to fix it in a
>> Maintenance Release as soon as possible, not tied to Java EE 8
>> planning or anything else.
>>
>> Proposed solution is to add two additional Session.addMessageHandler
>> methods with explicit type information, please see [2] for more
>> complete description. I also attached updated version of the
>> specification document. There is only one addition - last paragraph in
>> chapter 2.1.3 "Receiving Messages" and the sample code in chapter
>> 2.1.4 "Sending Messages" was modified to use the newly introduced
>> addMessageHandler method with explicit type.
>>
>> Complete change diff can be seen here [3] (but it contains lots of
>> noise - spec licence etc; changes.txt should be good enough for
>> evaluation).
>>
>> Any feedback would be greatly appreciated!
>>
>> Thanks and regards,
>> Pavel
>>
>> [1]: https://java.net/jira/browse/WEBSOCKET_SPEC-226
>> [2]:
>> https://github.com/pavelbucek/websocket-spec/blob/WEBSOCKET_SPEC-226/websocket-1.1-changes.txt
>>
>> [3]: https://github.com/pavelbucek/websocket-spec/pull/1/files
>