Just a quick note that the new behavior more closely matches the behavior of
the Async capabilities of the Servlet 3.0 spec. Longer term, as we move to
Jetty 8, we should be able to just use the Servlet 3 AsyncContext support for
this and simplify the code a bit.
Dan
On Tuesday 23 November 2010 7:04:10 am Sergey Beryozkin wrote:
> Hi Willem
>
> thanks for the explanation. It makes sense.
>
> However, when a user calls, for ex,
>
> continuation.suspend(60)
>
> there is no need to register a handler. This is a different kind of flow
> where a handler is registered and then that handler calls
> continuation.resume(). When we do
>
> continuation.suspend(60)
>
> we actually expect an invocation come back to us in the resumed state with
> the runtime itself initiating a resume event. I do not need to add a
> handler. I can check if some condition has been met when the invocation
> comes back.
>
> It is unfortunate Continuation is the interface otherwise we could add a
> method like suspendImmediately() may be.
>
> The Jetty wiki is showing
>
> continuation.suspend()
>
> which is the indefinite suspend thus there's a need there to wake up the
> pending thread from the application code.
>
> That said, having both timed suspends and async resumes at the same time
> makes sense too.
>
> Basically, having an explicit return is not a big issue, but it can make
> the user code a bit more involved.
>
> cheers, Sergey
>
> On Tue, Nov 23, 2010 at 4:52 AM, Willem Jiang <willem.ji...@gmail.com>wrote:
> > On 11/23/10 1:56 AM, Sergey Beryozkin wrote:
> >> Hi
> >>
> >> I've found out, while working with CXF Continuations API recently is
> >> that
> >>
> >> continuation.suspend()
> >>
> >> is returning normally and no SuspendedInvocationException is thrown.
> >>
> >> This is unexpected in that now, when continuation.suspend() is used
> >> directly
> >> in the application code, the explicit 'return' has to be added.
> >> This is not too bad when it is done immediately in the top-level service
> >> object but if it happens in one of the sub-routines we are effectively
> >> have
> >> no way of
> >> knowing at the start of the call if it was suspended or not, unless we
> >> use check the status explicitly :
> >>
> >> Ex :
> >>
> >> public void soapMethod() {
> >>
> >> doIt();
> >>
> >> if (!continuation.isPending()) {
> >>
> >> dontDoItIfSuspended();
> >>
> >> }
> >>
> >> }
> >>
> >> private void doIt() {
> >>
> >> continuation.suspend();
> >>
> >> }
> >>
> >> Willem - is it how the explicit continuations code has to be written now
> >> ?
> >>
> >> Yes, that is what I want to do in CXF 2.3.0.
> >
> > In this way we can implement suspend resume pattern[1] easily as Jetty 7
> > does.
> >
> > The main reason that continuation.suspend() does not return immediately
> > is letting the user have chance to setup the callback method for
> > contination resuming. In this way we can make sure the
> > continuation.resume() will never be called before the
> > continuation.suspend.
> >
> > thanks, Sergey
> >
> >> [1]
> >
> > http://wiki.eclipse.org/Jetty/Feature/Continuations#Suspend_Resume_Patter
> > n
> >
> > --
> > Willem
> > ----------------------------------
> > FuseSource
> > Web: http://www.fusesource.com
> > Blog: http://willemjiang.blogspot.com (English)
> >
> > http://jnn.javaeye.com (Chinese)
> >
> > Twitter: willemjiang
--
Daniel Kulp
dk...@apache.org
http://dankulp.com/blog
