GWT, with multiple clients

Question

Hi,

I am designing a web application using GWT currently, which is also the first time i am using GWT. I just have a general question about how (or can) GWT handles communications between multilpe clients.

My application needs user to login and has personalized pages for different users, GWT is well able to do all of these. The only problem is user needs to know what other users are doing, a simple example is like Google Talk, when one user is "typing", the other side will be noticed. So i am just wondering if GWT can do this?

As i said this is my first time using GWT, so, if GWT is well able to provide the these user interacting functions, i will go with GWT, otherwise i can make changes when it is not too late.

Thanks!!!

Answer 1

Looking at the example you gave, if user A starts typing, there's no problem sending the "started typing" event to the server. The server would than have to look up who user A is talking with (say, user B), and get the information to B's browser. This is, of course, the trickier part, but there is more than one way to perform the task, as described for instance here.

In summary, if you're OK with passing the requests through the server, I don't see a problem with using GWT as the underlying technology.

Answer 2

What you need is server push/ajax push/comet/many other names. I've summarized the options you have for GWT in a different answer.

For a quick start, check out NGiNX_HTTP_Push_Module - IMHO it's the easiest one to customize to your needs and they provide a nice chat example that should get you started. However, if you also use jQuery or Mootools in your application (for example, for UI effects), you might want to also consider Ajax Push Engine/APE-Project (but remember that jQuery/Mootools might require some tweaking to work with GWT). Those two are my favorites :)