Lecture 3

Learning Outcomes

At the end of this lecture, you’ll be able to:

• Criticize design decisions for a simple type hierarchy in Java made by employing inheritance mechanism.
• Recognize the usefulness of abstract classes and abstract methods to provide code reuse as well as a common interface among subtypes.
• Identify the syntax of Java Abstract Classes and contrast it with the syntax of Java Interfaces.
• Contrast the utility of abstract classes and interfaces.
• Catalogue class relationships into is-a and has-a classes and further separate is-a relationships into “extends” and “implements” types.
• Distinguish between interfaces and implementations.
• Define what is an Abstract Data Type (ADT).
• Declare an ADT using a Java interface, with complete Javadoc comments.
• Understand the importance and use of pre- and post-conditions for methods documentation.
• Write pre- and post-conditions for a given method definition within the Javadoc framework.