It has to be someway to access it. Indeed I never doing with any kind of program. I imagine they are two instances of the JVM and so must be conflictive..
For instance, reading rows from a JTable which is already running on another Java app. Id like to test programatically the results that are appearing there, running myTest app one Swing app is running
I ended up using FEST: http://fest.easytesting.org/
It can be used to simulate all imaginable human actions over the running swing app as well