![](../../../javaimages/course-previous.gif)
Language Elements
-
Single inheritance rooted in common
class Object
-
Subclassing builds new types
public class ExitableFrame
![](ob71spcr.gif) extends java.awt.Frame { ... }
- Support for mix-in "inheritance"
via Interfaces enhances opportunities for reuse
- Strongly type checked
- Most type checking performed statically
- Assignment type compatibility checked dynamically (if necessary)
- Access protection for classes, fields and methods
Detailed Description:
"With inheritance we have the ability to define a class by extending it from
another class. We can define a brand-new Frame called an ExitableFrame. I
developed that; it's not built into the system. Thereafter, we would say 'extends
java.awt.Frame'. This could represent any class that we want to be extended. In
this case, we're extending a specific class provided as part of the GUI library -- the
Abstract Window Toolkit or AWT. The package name is java.awt and the class
name is Frame. This is an explicit reference to a class. Later we'll talk about
implicit references by using the import statement."
![](../../../javaimages/course-previous.gif)
|