Fully implements application shutdown procedure that is invoked when the

user closes the the main gui window or invokes exit from the file menu.

src/main/java/io/github/dsheirer/source/tuner/TunerController.java

@@ -61,6 +61,11 @@ public abstract class TunerController implements Tunable, ISourceEventProcessor,
         mSourceEventListener = new SourceEventListenerToProcessorAdapter(this);
     }
 
+    /**
+     * Dispose of this tuner controller and prepare for shutdown.
+     */
+    public abstract void dispose();
+
     /**
      * Implements the ISourceEventListener interface to receive requests from sample consumers
      */