I've just been read my spec, it states - "[The user interface] must be composed exclusively with components from the Java Foundation Classes (Swing components).
The thing is, I've written a class that extends JFrame (to add additional functionality - namely the ability to dynamically edit the menu). Obviously it uses Swing but does it break the requirement (you do need to import more than javax.swing.* to make it work)?
I suspect I'm being too literal, I assume they meant exclusively Swing as opposed to AWT.
Of course you can use your helper class. Just make the source part of the programm. The rule here means you cannot use components from a third party. That is anything you have not written yourself and have to include in the JAR file to make your programm work.