I am running a simple java client through `java <class file>` command. The java command is actually invoked by a system process. This is on Unix.

We were facing problem with X11 Display. So we added `export DISPLAY=:0.0` in the startup file and the Display problem was resolved. Now when the `export DISPLAY=:0.0` line is removed from the startup file and the java client is run again, we are not able to revert to old state, i.e., we no longer get the X11 Display error. So there is something that is persisting on the system. Is there any way to make sure the JVM context was killed before running the client?

We have killed the process that triggers the java client, then restarted the process to run the java client again. But not succeeded to go back to the old state.

[Edit] I forgot to mention that I have already tried "unset DISPLAY" in the stop file. The startup fie is run when the environment is brought up and the stop file is run when the environment is brought down. I have also tried headless mode but that doesn't work for our program.