Java 6 Illuminated: An Active Learning Approach, 2nd Edition

10.1 Inheritance 655

Figure 10.1

Vehicle Class Hierarchy

Automobile Truck

Vehicle

Pickup TractorTrailer

been tested, we can reuse it with confidence by inheriting it into the sub-

classes. And when that common code needs revision, we need to revise the

code in only one place.

10.1 Inheritance

The syntax for defining a subclass class that inherits from another class is to

add an extends clause in the class header:

accessModifier class SubclassName extends SuperclassName

{

// class definition

}

The extends keyword specifies that the subclass inherits members of the

superclass. That means that the subclass begins with a set of predefined

methods and fields inherited ...