ERROR - java.lang.IllegalThreadStateException - Possible Causes of IllegalThreadStateException

Exception Thrown By:Cause
ClassMethod
Process public abstract int
exitValue()
if the sub process represented by
this Process object has not yet terminated.
Robot public void
waitForIdle()
if called on
the AWT event dispatching thread.
ThreadGroup public final void
destroy()
if the thread group is not empty
or if the thread group has already been destroyed.