Can a container contain a container?

A good answer might be:

Yes. In terms of a browser window you see this when a window contains frames.

Java Classes (review)

The component classes that make up the AWT and Swing are related to each other by inheritance. When you learn new GUI components it is important to see how they relate to other components.

In Java, there is a pre-defined class that is the ultimate ancestor of all other classes. This class is called Object. Object defines the basic nature of all Java objects. Much of what goes on behind the scenes when a Java program is running is defined by Object.

So, for example a small part of the Java class hierarchy looks like this:

The "clouds" convey the idea that these are class definitions, not objects. The diagram shows that the classes Boolean, Character, Component, String, and many others have Object as a direct ancestor. The cloud for the Component class is dotted to show that it is an abstract class.


(Review: ) Can a child class have methods and variables in addition to those it inherits from its parent?