This module is based on Chapter 8 of Introduction to Programming Using Java, by David J. Eck. Used with permission.

Computer programs that fail are much too common. Programs are fragile. A tiny error can cause a program to misbehave or crash. Programs don't have to be as bad as they are.

This module will look at issues of correctness and robustness of programs. It also looks more closely at exceptions and the try..catch statement, and it introduces assertions, another of the tools that Java provides as an aid in writing correct programs.

We will also look at another issue that is important for programs in the real world: efficiency. Even a completely correct program is not very useful if it takes an unreasonable amount of time to run. The last section of this chapter introduces techniques for analyzing the run time of algorithms.