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Hierarchical Visual Containment

It is difficult to imagine the context hierarchy unless a corresponding visual containment hierarchy displays it. Therefore, the first step is to add the ability to display nesting of visual containers. A visual container is any (instance of a) class extending the abstract class java.awt.Container.

The BeanBox class is a visual container; consequently, when adding new beans, you can place the new bean inside the environment. It is impossible in the standard BeanBox, however, to place a new bean inside another AWT container, which might be itself inside the BeanBox and displayed on the screen. By fixing this discrimination, our extension permits new beans to be created and placed inside any AWT container. As a result, you can form nested visual containers.