Implementing Server Push using LCDS 2.6

Hi All,
We have created an application where we are using polling to get certain constant updates. Now this polling is client polling wherein the client polls the server at regular intervals to get the fresh data for certain actions.
Now we wish to take this to another level and implement Server Data Push so that the client does not keep polling unnecessarily and the server notifies the client as and when the data gets updated with the server. For this we have the DataService Transaction class that needs to be implemented.
But there are a couple of questions that are in my mind regarding this technology. It would be great if someone could answer them.
My questions are:
1) Does the LCDS server know which client to push data to in case of multiple clients looking at the same data scenario. e.g. Two clients A and B are looking at the same data. A performs an action and that action needs some time to get completed at the server. Now in case we use Server Data Push, will the LCDS be intelligent enough to send the message on completion of the requested activity to only A and not B.
2) In order to push data to the client, the server will invoke some method which will return the desired data to te client. How do we keep the parameters registered with the server that this method would need while getting invoked. SInce, the call to the method will not be client initiated, how does the server know what parameters to be passed to the method in order to invoke it. How will this work in a multi-user looking at the same data/screen scenario.
The answers to these questions will really help us. In case anyone is well versed with this technology, please pitch in to give your inputs.
Many Thanks.
Regards,
Shally

Hi,
As also, suggested by you, we were thinking of using an RTMP channel only for this since its a two way socket that establishes a communication channel between the client and the server and then helps keep messages moving to and fro.
We have successfully implemented RTMP channel and achieved the following functionalities.
1) A client initiated change which gets propagated to the server and then to all the clients.
2) Server push to all the clients.
Now our last step is to implement data push to a particular client. As told by you, we will use the client id but we have some doubts and questions regarding this since we do not have the code examples or anything that could help us in implementing the same.
I would therefore request you to kindly lead us on the following fronts:
1) Is the client id the one that is part of the request- response thread, I saw a client id being printed in the logs when a request is made and the response comes.
2) What code needs to be written on the server side to extract this client id once a call is made so that it can keep this client id with itself to push a message later on.
3) What methods or API are available to be used to push this message to a particular client? Do we need to call the fill method of a particular client using the client id parameter and inform the client that its requested job has been done.
For (3) is the Messaging(Publish and Subscribe model) the right way to go??
It would be great if you could provide us some code snippets just to give us an idea from where we can take it up ourselves.
Looking forward to hear from you.
Many Thanks,
Shally
Message was edited by: testing34

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I read the OP's message and imediately thought oh, cool, MVC candidate :-)          If I wanna talk about MVC I would prefer Sun's Design Patterns group.
          Kumar.
          [email protected] wrote:
          > "Mettu Kumar" <[email protected]> wrote in message
          > news:[email protected]...
          > > Ryan,
          > >
          > > I was not commenting on MVC pattern. I am talking about the problems
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          > Mettu, we completly crossed paths my friend. I read the OP's message and
          > imediately thought oh, cool, MVC candidate :-) Silly me! I understand what
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          >
          > >
          > > Kumar.
          > >
          > > [email protected] wrote:
          > >
          > > > I wasn't referring to the article on pushlets you mentioned when I said
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          > > > ~Ryan
          > > >
          > > > "Mettu Kumar" <[email protected]> wrote in message
          > > > news:[email protected]...
          > > > > Ryan,
          > > > >
          > > > > Did you ever try to use to Pushlets serving thousands of clients?
          > > > > Why did you think its a good design? If you feel its a good design,
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          > > > >
          > > > > Kumar.
          > > > >
          > > > > [email protected] wrote:
          > > > >
          > > > > > "Mettu Kumar" <[email protected]> wrote in message
          > > > > > news:[email protected]...
          > > > > > > Vikas,
          > > > > > >
          > > > > > > There was a article about the same in java world a while back.
          > > > > > > http://www.javaworld.com/javaworld/jw-03-2000/jw-03-pushlet.html
          > > > > > >
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          > > > serving
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          > > > > > > of hundred clients?
          > > > > > >
          > > > > > > Kumar.
          > > > > > >
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          > > > > > It's a perfectly valid design. OP, check out MVC and the observer
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          > > > > >
          > > > > > ~Ryan
          > > > > >
          > > > > > > Vikas Jolly wrote:
          > > > > > >
          > > > > > > > Hi AnyOne!
          > > > > > > >
          > > > > > > > I have a servlet, and a database . If a column in my table gets
          > > > updated
          > > > > > I
          > > > > > > > want all of my clients who are connected to it , to see the
          > > > refreshed
          > > > > > value
          > > > > > > > without click any refresh/Reload button on the browser. A kind
          > of
          > > > > > > > Server-Push.
          > > > > > > > That is, If one client makes changes, then all of the other
          > clients
          > > > on
          > > > > > the
          > > > > > > > web should get intimated.
          > > > > > > >
          > > > > > > > How can I achieve this ?
          > > > > > > >
          > > > > > > > thanks
          > > > > > > > vikas
          > > > > > >
          > > > >
          > > > >
          > >

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