you mean a OS level user ?
JBoss IDE is used to run/debug jboss as for application development and to do that we launch jboss app server from within eclipse in a seperate JVM. That JVM is always started by the current user.
If you are talking about the jboss as level user to stop and adminster an installation then that is (currently) done in the launch configuration by editing the shutdown and twiddle commands where you can set -user and -password to the relevant values.
Where I can set this values? Nor in run.sh neighter in shutdown I found these values or a location where I can set it?
you set that in the launch configuration of the server.
you set them by entering them into the command line arguments field.