HTML and CSS Reference
Atmosphere is the only portable WebSocket/Comet framework supporting Scala, Groo‐
web server, including Tomcat, Jetty, GlassFish, Weblogic, Grizzly, JBoss, Resin, and
components. You can find many examples of how to use Atmosphere in your project at
https://github.com/Atmosphere/atmosphere/tree/master/samples ( Figure 5-1 ).
The main concern when using WebSockets is graceful degradation, be‐
cause most mobile browsers and servers have mixed support. All the
frameworks mentioned (plus many more) support some kind of fallback
when WebSockets is not available within the browser. All of these fall‐
backs, however, share the same problem: they carry the overhead of
HTTP, which doesn't make them well suited for low-latency mobile
applications. Until all mobile browsers support WebSockets, this is a
problem users and developers are forced to deal with.