Lecture 8 Objectives

At the end of today's class you should

KNOW:

that in Java, interfaces may extend other interfaces
that you should use an interface if you want the flexibility of using different implementations of the same datatype
that a cast is a way to tell Java you're confident of the type of an object
that a cast can remove compilation errors, but if used incorrectly, it may introduce runtime errors

BE ABLE TO:

use an interface in Java as a means to provide multiple implementations of a type
create instances of a data structure (like a set) where each instance uses a different underlying implementation
know when and how to use a cast

Sample Exam Question:

Sketch out the UML diagram for an AVL tree implementation of an ISet (you don't have to write code at this point, just draw the UML). Then, rewrite the Examples class from today's code so that the PartyGuests object PG uses your AVL implementation of ISet.