How is the LAUNCH_JBOSS_IN_BACKGROUND used by the run.sh script in JBoss EAP

Issue

• I wanted to start JBoss EAP 6.x server in background mode.

• I wanted to start the JBoss process in background while running run.sh and also wanted it to keep on running after closing that session also, so instead of running it with nohup and & I was trying to understand the script if something can be modified inside the script. What I found is, at one place its checking for a condition

  if [ "x$LAUNCH_JBOSS_IN_BACKGROUND" = "x" ] 
  

but I never found the variable LAUNCH_JBOSS_IN_BACKGROUND being defined anywhere, that means every time it will run in foreground.

• Why it is written in that way and what can be modified within the script to run it in background without killing the process after closing the session.