How to tell client disconection reason when invoke disconnect() on the server side.

Question

Is there any way to tell client the reason for disconect when I call disconect() on the server side. its some way like using error object as optional parameter to include reject reason when invode rejectConnection

Answer 1

Ignore the JSRs for now.
Follow the JavaEE tutorial.
http://docs.oracle.com/javaee/6/tutorial/doc/
The answers to many of your questions will be clear to you once you have completed the tutorial.
I also like the tutorials here (they are a little dated, but still mostly relevant as the core JEE6 specs that the tutorial relies on were released over 5 years ago and JEE7 is yet to be released).
https://schuchert.wikispaces.com/EJB+3+and+Java+Persistence+API
zonski has a spring+javafx focused tutorial if you would prefer to learn and use Spring than JEE (they are differing technologies which cover pretty much the same functional set):
http://www.zenjava.com/series/building-jee-applications-in-javafx-2-0/
JavaFX is a client side framework so there is not much you would do with it on the server side.
It seems like there is a ton of "JSR's" for different tasks, and I'm not sure exactly what I need, and all that, so I'm really confusedNobody needs all of JEE, just use the bits that you want that are a good fit for whatever project you are doing - don't try to use everything at once.
A lot of the stuff can be learnt and used in isolation.
Selected relevant topics, might be (in the order that I would consider them):
Persistence: http://docs.oracle.com/javaee/6/tutorial/doc/bnbpy.html
Java Servlet Technology: http://docs.oracle.com/javaee/6/tutorial/doc/bnafd.html
JAX-RS web services: http://docs.oracle.com/javaee/6/tutorial/doc/giepu.html
Contexts and Dependency Injection: http://docs.oracle.com/javaee/6/tutorial/doc/gjbnr.html
Enterprise Beans: http://docs.oracle.com/javaee/6/tutorial/doc/bnblr.html