How to Login to various java application using single custom login application form

I want some guidance. I got a requirement that there should be one login application form which will show 5 icons (there are 5 J2EE application in backend), after login, If, user clicks any icon then that application should open in new tab. We are able to create custom login form and able to show 5 icons. Now the main question is how to login that clicked icon application and show the home page of that application.

We are using JBoss 7 Container for this requirement.

Please provide your valuable insinght in this requirement.