The purpose of object-oriented programming is to build your actual system, to develop the code that fulfills your system's design. Your design artifacts, such as unified modeling language (UML) class and state machine diagrams, drive the development of your source code. Design and programming are highly interrelated and iterative and you will often move back and forth between them. Your programming efforts will quickly reveal weaknesses in your design that need to be addressed, and your design efforts will reveal potential strategies to code the system effectively.

Developers will typically focus on two types of source code: object-oriented code, such as Java or C#, and database-oriented code, such as data definition language (DDL), data manipulation language (DML), stored procedures, and triggers. Section 13.4 describes how to implement common object-oriented concepts in Java and Chapter 14 describes database coding. The end goal of your programming efforts is to produce a component, subsystem, or even a full-fledged application that can undergo testing in the large (described in Chapter 3).

This chapter discusses these topics:

• Philosophies for effective programming;

• Programming tips and techniques for writing high-quality code;

• Test-driven development (TDD);

• From object design to Java code; and

• What you have learned.

PHILOSOPHIES FOR EFFECTIVE PROGRAMMING

Over the years I have found that the following philosophies have helped improve my effectiveness as a programmer:

1. Always write high-quality, clean code. Quality work is one of the practices of extreme programming (XP) (Beck 2000), and my experiences confirm the importance of writing high-quality code at all times. High-quality code is easier to write, easier to understand, and easier to enhance. Sloppy code will only slow you down.

2. […]