GWT Server Push using Jetty Continuations? -

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i'm supposed implement web application user log's in , registers sort of events (in case, alarms). when alarm happens, server needs push alarm of clients.

at moment i'm using

  • gwt on client side
  • jetty on server side

is implementing server push using jetty continuations idea? requirements are:

  • the number of clients quite small (<20) increase in future
  • alarms must not lost (i.e. if client down, must not miss alarms)
  • if client goes down, other clients need informed (or @ least admin should receive sort of notification, e.g. mail).

the main reason using comet (e.g. jetty continuations) is, allows reduce polling frequency. in other words: can achieve same thing without comet, using frequent polling client side. alternative choose depends on characteristics of application - depending on that, each alternative can more or less efficent other!

in case, since need notifications when client goes down, makes sense use frequent polling. comet (long polling) not suited task: because of priciple, can take long time until client sends new request. , receiving new request way server can know client still alive (remember, web server - no matter if comet or not - can never send request client).


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