I've found a class in the API that does almost everything I need it to do. However, in addition to what it does, I also need it to store a couple extra variables. The class is java.awt.polygon, and I need it to store simple variables like a name, id and description - no additional methods. It seems like this should be do-able. Is this a case where I am extending an existing class? Can someone point me to a place where I can learn more about how to do this?