School of Computer Science University of KwaZulu-Natal February 5, 2007
Object Oriented Programming using Java
Notes for the Computer Science Module Object Oriented Programming COMP200
Adapted from Introduction to Programming Using Java Version 5.0, December 2006 by David J. Eck http://math.hws.edu/javanotes/ Adapted by Anban Pillay School of Computer Science University of KwaZulu-Natal Durban February 2007
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Contents
1 Introduction to Objects 1.1 What is Object Oriented Programming? . . . . . . . . . . . . . . 1.1.1 Programming Paradigms . . . . . . . . . . . . . . . . . . . 1.1.2 Object Orientation as a New Paradigm: The Big Picture 1.2 Fundamentals of Objects and Classes . . . . . . . . . . . . . . . 1.2.1 Objects and Classes . . . . . . . . . . . . . . . . . . . . . . 1.2.2 Class Members and Instance Members . . . . . . . . . . 1.2.3 Access Control . . . . . . . . . . . . . . . . . . . . . . . . . 1.2.4 Creating and Destroying Objects . . . . . . . . . . . . . . 1.2.5 Garbage Collection . . . . . . . . . . . . . . . . . . . . . . 1.2.6 Everything is NOT an object . . . . . . . . . . . . . . . . . 2 The Practice of Programming 2.1 Abstraction . . . . . . . . . . . . . . . . . . . . . 2.1.1 Control Abstraction . . . . . . . . . . . . . 2.1.2 Data Abstraction . . . . . . . . . . . . . . 2.1.3 Abstraction in Object-Oriented Programs 2.2 Methods as an Abstraction Mechanism . . . . . 2.2.1 Black Boxes . . . . . . . . . . . . . . . . . 2.2.2 Preconditions and Postconditions . . . . . 2.2.3 APIs and Packages . . . . . . . . . . . . . 2.3 Introduction to Error Handling . . . . . . . . . . 2.4 Javadoc . . . . . . . . . . . . . . . . . . . . . . . . 2.5 Creating Jar Files . . . . . . . . . . . . . . . . . . 2.6 Creating Abstractions . . . . . . . . . . . . . . . 2.6.1 Designing the classes . . . . . . . . . . . . 2.7 Example: A Simple Card Game . . . . . . . . . . 3 Tools for Working with Abstractions 3.1