Bug Patterns in Java

Bug Patterns in Java presents a methodology for diagnosing and debugging computer programs. The act of debugging will be presented as an ideal application of the scientific method. Skill in this area is entirely independent of other programming skills, such as designing for extensibility and reuse. Nevertheless, it is seldom taught explicitly. Eric Allen lays out a theory of debugging, and how it relates to the rest of the development cycle. In particular, he stresses the critical role of unit testing in effective debugging. At the same time, he argues that testing and debugging, while often conflated, are properly considered to be distinct tasks.

Upon laying this groundwork, Allen then discusses various "bug patterns" (recurring relationships between signaled errors and underlying bugs in a program) that occur frequently in computer programs. For each pattern, the book discusses how to identify them, how to treat them, and how to prevent them.

Table of Contents

1. Agile Methods in a Chaotic Environment
2. Bugs, Specifications, and Implementations
3. Debugging and the Development Process
4. Debugging and the Testing Process
5. The Scientific Method of Debugging
6. About the Bug Patterns
7. The Rogue Tile
8. Null Pointers Everywhere!
9. The Dangling Composite
10. The Null Flag
11. The Double Descent
12. The Liar View
13. Saboteur Data
14. The Broken Dispatch
15. The Impostor Type
16. The Split Cleaner
17. The Fictitious Implementation
18. The Orphaned Thread
19. The Run-On Initialization
20. Platform-Dependent Patterns
21. A Diagnostic Checklist
22. Design Patterns for Debugging
23. References

Bug Patterns in Java presents a methodology for diagnosing and debugging computer programs. The act of debugging will be presented as an ideal application of the scientific method. Skill in this area is entirely independent of other programming skills, such as designing for extensibility and reuse. Nevertheless, it is seldom taught explicitly. Eric Allen lays out a theory of debugging, and how it relates to the rest of the development cycle. In particular, he stresses the critical role of unit testing in effective debugging. At the same time, he argues that testing and debugging, while often conflated, are properly considered to be distinct tasks.

Upon laying this groundwork, Allen then discusses various "bug patterns" (recurring relationships between signaled errors and underlying bugs in a program) that occur frequently in computer programs. For each pattern, the book discusses how to identify them, how to treat them, and how to prevent them.

Eric Allen has a bachelor's degree in computer science and mathematics from Cornell University, and is a Ph.D. candidate in the Java programming languages team at Rice University. His research concerns the development of semantic models and static analysis tools for the Java language, both at the source and bytecode levels. Currently, Eric is constructing a compiler for the NextGen programming language, an extension of the Java language with added language features. He has also moderated the Java Beginner discussion forum at JavaWorld and is a project manager of DrJava, an open source Java IDE designed for beginners.