New class to support attributes
New class to support class
Add SAVE_TIMEOUT parameter to specify how long the save message persists
Add draw function. Modify save/load to work with elements
Add function to add a Class to the current diagram. Set up draw function to call draw on current diagram.
Set up DiagramPanel in the scroll pane so that it's graphics object can be passed into the diagram and be drawn on.
Change to an interface. Don't want it to be a class because you can't have just a DiagramElement.
Create an exit() function and have it called both when the user does File->Exit or clicks the red X at the top right.
New class to support Operations (why did he not call it method?)
New class to support Parameters of Operations
New enumeration to support public/private/protected
Added this in so everybody can access the getValueFromTag function that's needed by DiagramElements, Operations, Attributes, and Parameters. Little bit unclean to make it's own class for this, but seemed like the easiest way without using XML schema and complicating things.