Hi Michael: I apologize for the delayed response.
If you use GWT and say GWT-RPC for example, this will all be handled for you. Since each client will get its own session. The real challenge is going to be if my memory serves me right according to your initial requirements knowing when your client stopped working for whatever reason, be it that something went south or as you previously mentioned the user simply closed the browser. This is part of the reason why I recommended errai so you would have a nice easy-to-use server push implementation. There are others or you can have your own and rely on Jetty continuations for instance. Again, sorry for the delayed response, had a few emails piled up and missed this one. Alfredo On Tue, May 1, 2012 at 10:54 PM, mmorckos <mikey.morc...@gmail.com> wrote: > Thanks for the prompt reply. I've been experimenting with gwt for a > little while and due to time constrains I'd rather not try > other tools, but thanks for the suggestion. > > I have another question (excuse my little experience with web > application), I'd like to know how the a Servlet on the server-side > can efficiently keep track of all connected clients since in my > application, for each connected client the Servlet will instantiate a > regular Java object with its own state for each client. Basically each > client will interact with its own object through the Servlet. > > I know this is a bit of an overhead, but as I mentioned before I'm > building a web-tier for a back-end platform that's not web oriented. > > Regards, > Michael > > On Apr 27, 4:59 pm, Alfredo Quiroga-Villamil <laww...@gmail.com> > wrote: >> Thanks. I think Joseph said it before and I agree with him. If it's >> something of that nature, I would likely try to stay from web stuff. >> However, that doesn't mean is not possible or there are no ways to >> ensure what you want. >> >> I recently had the chance to speak with a few guys at RedHat about a >> project they have been working on based on GWT. I've been meaning to >> let people know about it because I was really impressed by a couple of >> things I saw. One of them can truly help you and make your requirement >> easier or a lot easier to implement. >> >> http://www.jboss.org/errai >> >> A few things: >> >> a) You don't need jboss to use it. >> b) Take special attention to CDI (crazy cool and useful). >> c) They've done something really interesting where you truly have a >> transparent web/server application, blurring completely the lines >> between server and UI. Via an annotation you have Server Push. Their >> Dependency Injection I thought was also nicer than GIN for the UI. >> Although I use GIN and love it! >> >> So what you could do, assuming that you truly want to keep this web >> based is to have the server contacting the UI every x amount of >> seconds. If no response is received from the UI, then you know that >> something is not right. That would be better I think than polling the >> server. >> >> Again, this could be done without errai, but take a look at it if you >> get a chance. >> >> Best regards, >> >> Alfredo >> >> >> >> >> >> >> >> >> >> On Fri, Apr 27, 2012 at 4:44 PM, mmorckos <mikey.morc...@gmail.com> wrote: >> > What I meant by "crash" is that the client doesn't "cleanly". For >> > instance, the user can simply close the web-page, or the client's >> > machine can lose connection to the server. I'm asking if there is a >> > way that the server can detect that instantly (some sort of a >> > heartbeat ping between the client and the server, unlike a session >> > timeout). >> >> > On Apr 27, 10:47 am, Alfredo Quiroga-Villamil <laww...@gmail.com> >> > wrote: >> >> Can you please define or explain what you mean by "whenever a client >> >> crashes"? >> >> >> Thank you in advance, >> >> >> Alfredo >> >> >> On Fri, Apr 27, 2012 at 1:49 AM,mmorckos<mikey.morc...@gmail.com> wrote: >> >> > Hello, >> >> >> > I'm intending to develop a web-based frontend UI for a control system >> >> > in a research lab. For safety purposes, it's vital that when a client >> >> > crashes, the server is notified immediately and dispatches a stop >> >> > signal to all connected machinery. >> >> >> > I'm new to gwt and would like to know if there is a way to know >> >> > whenever a client crashes on the server side, specifically inside a >> >> > "RemoteServiceServlet". >> >> >> > Regards, >> >> > Michael >> >> >> > -- >> >> > You received this message because you are subscribed to the Google >> >> > Groups "Google Web Toolkit" group. >> >> > To post to this group, send email to >> >> > google-web-toolkit@googlegroups.com. >> >> > To unsubscribe from this group, send email to >> >> > google-web-toolkit+unsubscr...@googlegroups.com. >> >> > For more options, visit this group >> >> > athttp://groups.google.com/group/google-web-toolkit?hl=en. >> >> >> -- >> >> Alfredo Quiroga-Villamil >> >> >> AOL/Yahoo/Gmail/MSN IM: lawwton >> >> > -- >> > You received this message because you are subscribed to the Google Groups >> > "Google Web Toolkit" group. >> > To post to this group, send email to google-web-toolkit@googlegroups.com. >> > To unsubscribe from this group, send email to >> > google-web-toolkit+unsubscr...@googlegroups.com. >> > For more options, visit this group >> > athttp://groups.google.com/group/google-web-toolkit?hl=en. >> >> -- >> Alfredo Quiroga-Villamil >> >> AOL/Yahoo/Gmail/MSN IM: lawwton > > -- > You received this message because you are subscribed to the Google Groups > "Google Web Toolkit" group. > To post to this group, send email to google-web-toolkit@googlegroups.com. > To unsubscribe from this group, send email to > google-web-toolkit+unsubscr...@googlegroups.com. > For more options, visit this group at > http://groups.google.com/group/google-web-toolkit?hl=en. > -- Alfredo Quiroga-Villamil AOL/Yahoo/Gmail/MSN IM: lawwton -- You received this message because you are subscribed to the Google Groups "Google Web Toolkit" group. 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