Roles in associations in class diagrams

Came across this:


I noticed the line which said

When code is generated for class diagrams, named association ends become instance variables in the target class.

So naturally I tried to plug this into Visual Paradigm, and after fiddling around with it for a while I got them to appear with the right syntax. Then I pressed the generate code button, and voila - everything done in a jiffy.

So all you have to do really is to notate the multiplicity on either end of the association (or aggregation, or composition), then add a role name to the child class, then set the visibility of the role (usually "-" for private). Once this is done, you have told VP all it needs to know to generate the code, complete with ArrayLists and everything.

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In an unrelated note, I have discovered an annoying little bug in VP, where you have a class that inherits from a parent class, the Java code it should convert to is

public class Child extends Parent {...

However, for some weird reason, the code it outputs (sometimes, and sometimes not), is

public class Child extends Parent implements Parent {...

Which doesn't make sense, because you would never be in a situation where one class would need to extend and implement the same class at the same time.