On 1/31/13 6:11 PM, Scott Ferguson wrote:
> On 1/31/13 5:13 PM, Danny Coward wrote:
>> Hi folks,
>>
>>
>>
>> * Validity of message objects
>> (http://java.net/jira/browse/WEBSOCKET_SPEC-122)
>>
>> Mark and I have exchanged comments over on the JIRA issue for this:
>> for the message objects that can be passed into the various
>> MessageHandlers, should they remain valid after the completion of the
>> onMessage call ? for example if the implementation passes in a
>> ByteBuffer to represent a binary message, can the developer be sure
>> that it won't be recycled after the onMessage call has completed.
>>
>> I'd say it would be easier for developers if they could uses these
>> message objects outside the scope of the onMessage call, any other
>> opinions ?
>>
>
> It's pretty important that these objects be owned by the container and
> lose scope after the message handler.
>
> The need is most clear in the case of InputStream and Reader (because
> their data is no longer live outside the call). But also ByteBuffer,
> since that's designed to avoid buffer copies. The underlying data for
> the ByteBuffer could conceivably be non-heap memory.
OK. I guess it could get ugly if the developer held on to an InputStream
and decided to try to read it a month later (!), and I think Mark thinks
mutable objects should go out of scope too.
Looking through the list of possible message objects in both the
annotated/programmatic message handlers, we have
String
Reader
byte
ByteBuffer
InputStream
Java primitives / class equivalents
developer objects derived from decoders wholly consuming the incoming
message.
would you think it reasonable to say that Reader/InputStream/ByteBuffer
messages should not be references outside the scope of the message
handler callback, but its ok for developers to reference the other types
outside that scope ?
- Danny
>
> -- Scott
>
--
<http://www.oracle.com> *Danny Coward *
Java EE
Oracle Corporation