Help with classes in Netbeans

I have created a singleton classes and these classes got imported in program by netbeans.Please , tell me the description of following classes, i m not getting the functions of these in my program:

org.jdesktop.application.Action;
org.jdesktop.application.ResourceMap;
org.jdesktop.application.SingleFrameApplication;
org.jdesktop.application.FrameView;
org.jdesktop.application.TaskMonitor;