Java Reference
In-Depth Information
Figure 3-7.
More important, we have proven that the JRE classes are composed of many other classes/objects. In fact, every
JRE class is involved in a superclass/subclass relationship and the JRE classes inherit many of their capabilities from
specialization (i.e., from their superclasses). For example, Figure
3-8
shows how several of the GUI classes are related
in a hierarchy. Notice that
Frame
is a type of
Window
and that a
Label
is a type of
Component
.
Object
Component
Label
Button
Container
TextComponent
Window
Panel
TextField
Frame
Applet
Figure 3-8.
