<AWT Dev> EventQueue changes

[Oleg Sukhodolsky]

On Tue, Sep 9, 2008 at 3:55 PM, Artem Ananiev <Artem.Ananiev at sun.com> wrote:
> Hi, AWT team,
>
> there are several issues related to EventQueue class with a long history.
> The number of user votes constantly grows, so I think it would be fine if we
> can get them fixed in some nearest future.
>
> The list of bugs include (but not limited to):
>
> 6424157: java.awt.EventQueue push/pop might cause threading issues
>
> 6542185: Threading issues with java.awt.EventQueue.push/pop
> (closed as not a defect, but some of described problems still exist)
>
> 4913324: Deadlock when using two event queues.
>
> 4516924: Request public access to pumpEvents(Conditional) type
> functionality.
>
> 6727884: Some Uncaught Exceptions are no longer getting sent to the Uncaught
> Exception Handlers
>
> Some of the described problems don't look related to each other, however
> after a closer look I found they really do. That's why I listed them here
> altogether, and would like to discuss some possible improvements:
>
> 1. Synchronization changes. Most of the problems with push/pop are caused by
> imperfect synchronization in EventQueue. Currently, all the actions like
> postEvent() or getNextEvent() are transferred back and forth in the stack of
> event queues, and each queue is accessed in its 'synchronized' block.
> Instead, a single lock looks more correct here.
>
> 2. EventDispatchThread lifecycle. It is a known fact, that event dispatch
> thread may die for some reason (for example, because of unhandled
> exception). When a new event comes, new EDT is created. Another case when
> EDT is switched is push/pop methods: when a new EQ is pushed/popped, a new
> EDT is created.
>
> I'm sure these changes of current dispatch thread is not what developers
> expect. Swing is considered as single-threaded toolkit, but it is really
> not...
>
> 3. Controllable event pump. This is what developers have been requesting for
> at least 8 years. With the current API this task cannot be solved, and all
> the external libs like Foxtrot are really just hacks and depend on JDK
> internals.
>
> From technical point of view, controllable event pump is just a several
> lines of code changes: we only need to make public the code which is used
> for modality event pumps.
>
> ----
>
> I have a prototype fix with all the three items implemented. Still, it would
> be fine to hear what all AWT developers think about proposed changes.

I see list of problems, but do not see list of proposed changes :(
Did I miss something?

With best regards, Oleg.