tomcat-users mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From yangyuexiang <yangy...@comp.nus.edu.sg>
Subject Re: How to process events in jsp?
Date Tue, 05 Sep 2000 07:00:13 GMT

Amos Shapira wrote:

> Hi,
>
> I'm not quite familiar with JAvaBean events, but it sounds like
> maybe you can have a specialized object created per-request,

I expected only one client request occurred. And after that, the server
will update
the display in the client  when the server has new results (or when the jsp
engine receive
a event from my java bean). This seems impossible except some scripts
written for  the clients.

By the way, who can tell me which meta command for clients can make
requests
every 10 seconds. I forgot this now.

Thanks
yangyuexiang

>
> (pass it the "out" object in the construction or something) listen
> to the JavaBean and send the events to the client.
>
> I don't think there is much sense in a per-session "out" object since
> it represents a client connetion.
>
> Hope this helps,
>
> --Amos
>
> > -----Original Message-----
> > From: yangyuexiang [mailto:yangyuex@comp.nus.edu.sg]
> > Sent: Tuesday, September 05, 2000 9:34 AM
> > To: tomcat-user@jakarta.apache.org
> > Subject: How to process events in jsp?
> >
> >
> > Sorry for my not clear information.
> >
> > My java bean (designed to do some time consuming work such as
> > optimization) will call firePropertyChange(...) methods during its
> > running. In normal java application, there is a PropertyChangeListener
> > instance.
> >
> > In the jsp file, the bean is called (However, I donot want
> > the servlet to
> > extend PropertyChangeListener) . The bean will generate a serial of
> > events by calling "firePropertyChange" method. I want to send
> > the message
> > related to these events to the clients.
> >
> > The difficulty is:
> > (1) How can the servlet receive these events. I can solve it by adding
> > one PropertyChangeListener
> > instance in jsp and let it listen the bean which has session
> > scope. But I
> > am not sure whether it is the best way.
> > (2) What is the scope of "out" object? Can I have a "out" object which
> > has session scope? Does it means I must abandon the implicit
> > out object
> > and define a new JspWriter instance myself? Then, how can I send the
> > messages back to the clients because the clients donot know
> > whether there
> > is a new message generated in the server?
> >
> > Regards
> > yangyuexiang
> >
> >
> > Ralph Einfeldt wrote:
> >
> > > I think you must supply a bit more info to get helpfull answers.
> > >
> > > What do mean with events?
> > > How are the events realised (Exceptions, AWT Events, JMS, ...)?
> > > How do the events communicate with the outside world
> > > (in process, sockets)
> > >
> > > > -----Urspr√ľngliche Nachricht-----
> > > > Von: Yang Yue Xiang [mailto:yangyuex@comp.nus.edu.sg]
> > > > Gesendet: Dienstag, 5. September 2000 04:50
> > > > Cc: tomcat-user@jakarta.apache.org
> > > > Betreff: How to process events in jsp?
> > > <snip/>
> > > > I want to call  a java bean in a jsp file.
> > > > But this java bean will generate events during its
> > running because I
> > > > used events to communicate with outside world. These
> > events contain
> > > > the running results. Does it possible for me to output the results
> > > > dynamically to the clients? How to do? Any suggestions
> > are welcome!
> > > <snip/>
> >


Mime
View raw message