Abstract

This loads the package.

We define a class with an abstract method. The access must not be Public, but Protected or Private.

It is now abstract.

We now define the class such that it is no longer abstract. Although the method in the parent class is abstract, its code is accessible through the child class. In order to force implementation of an interface, the right hand side of the definition of the abstract method could contain a Throw[] statement. We use Override to underline that parent class functionality is changed.