# Code, Explanations and Solutions Companion > Java versions, incremental deltas, lab solutions, and instructor verification records --- LLMS index: [llms.txt](/ood-agile-book/llms.txt) --- *Companion to Object Oriented Development and Agile Practices* - [Chapter 1 Companion: Code, Explanations and Solutions](/ood-agile-book/companion/chapter-01/) - [Chapter 2 Companion: Code, Explanations and Solutions](/ood-agile-book/companion/chapter-02/) - [Chapter 3 Companion: Code, Explanations and Solutions](/ood-agile-book/companion/chapter-03/) - [Chapter 4 Companion: Code, Explanations and Solutions](/ood-agile-book/companion/chapter-04/) - [Chapter 5 Companion: Code, Explanations and Solutions](/ood-agile-book/companion/chapter-05/) - [Chapter 6 Companion: Code, Explanations and Solutions](/ood-agile-book/companion/chapter-06/) - [Chapter 7 Companion: Code, Explanations and Solutions](/ood-agile-book/companion/chapter-07/) - [Chapter 8 Companion: Code, Explanations and Solutions](/ood-agile-book/companion/chapter-08/) - [Chapter 9 Companion: Code, Explanations and Solutions](/ood-agile-book/companion/chapter-09/) - [Chapter 10 Companion: Code, Explanations and Solutions](/ood-agile-book/companion/chapter-10/) - [Chapter 11 Companion: Code, Explanations and Solutions](/ood-agile-book/companion/chapter-11/) - [Chapter 12 Companion: Code, Explanations and Solutions](/ood-agile-book/companion/chapter-12/) - [Chapter 13 Companion: Code, Explanations and Solutions](/ood-agile-book/companion/chapter-13/) - [Chapter 14 Companion: Code, Explanations and Solutions](/ood-agile-book/companion/chapter-14/) - [Chapter 15 Companion: Code, Explanations and Solutions](/ood-agile-book/companion/chapter-15/) - [Appendix A Companion: Code, Explanations and Solutions](/ood-agile-book/companion/appendix-a/) - [Appendix B Companion: Code, Explanations and Solutions](/ood-agile-book/companion/appendix-b/) - [Appendix C Companion: Template Kit and Checker](/ood-agile-book/companion/appendix-c/) - [Appendix F Companion: The Risk Lab](/ood-agile-book/companion/appendix-f/) This section contains the official code companions, lab walkthroughs, and verified solutions for each chapter of *Object Oriented Development and Agile Practices*. ### Companion Content Structure Every chapter's companion provides: 1. **Executable Java Code Listings**: Production-quality Java classes and suites conforming to the running Campus Equipment Lending System. 2. **Step-by-Step Code Walkthroughs**: Line-by-line analyses of design decisions, type safety, invariants, and exception handling. 3. **Lab Solutions & Exercises**: Model answers for both required core labs and optional team extensions. 4. **Verification Records & Fault Experiments**: Documented test suite outputs (`mvn verify`), mutation/fault analysis records, and reproducible compiler checks. 5. **Delta Versions**: Clear listings of new or modified files built on top of preceding chapter versions. Select a chapter or appendix companion from the sidebar or table of contents to view its complete code listings and solutions. > 📘 **Note on Appendices:** Code companions are provided for Appendices A, B, C, and F (which contain runnable listings, diagnostic code, and validation tools). Appendix D (Project Versions and Glossary) and Appendix E (Critical Reading and Project Evidence) are comprehensive non-code reference guides contained directly within the main textbook. --- Section pages: - [Chapter 1 Companion: Code, Explanations and Solutions](/ood-agile-book/companion/chapter-01/): Code explanations and solutions for Chapter 1 Companion: Code, Explanations and Solutions. - [Chapter 2 Companion: Code, Explanations and Solutions](/ood-agile-book/companion/chapter-02/): Code explanations and solutions for Chapter 2 Companion: Code, Explanations and Solutions. - [Chapter 3 Companion: Code, Explanations and Solutions](/ood-agile-book/companion/chapter-03/): Code explanations and solutions for Chapter 3 Companion: Code, Explanations and Solutions. - [Chapter 4 Companion: Code, Explanations and Solutions](/ood-agile-book/companion/chapter-04/): Code explanations and solutions for Chapter 4 Companion: Code, Explanations and Solutions. - [Chapter 5 Companion: Code, Explanations and Solutions](/ood-agile-book/companion/chapter-05/): Code explanations and solutions for Chapter 5 Companion: Code, Explanations and Solutions. - [Chapter 6 Companion: Code, Explanations and Solutions](/ood-agile-book/companion/chapter-06/): Code explanations and solutions for Chapter 6 Companion: Code, Explanations and Solutions. - [Chapter 7 Companion: Code, Explanations and Solutions](/ood-agile-book/companion/chapter-07/): Code explanations and solutions for Chapter 7 Companion: Code, Explanations and Solutions. - [Chapter 8 Companion: Code, Explanations and Solutions](/ood-agile-book/companion/chapter-08/): Code explanations and solutions for Chapter 8 Companion: Code, Explanations and Solutions. - [Chapter 9 Companion: Code, Explanations and Solutions](/ood-agile-book/companion/chapter-09/): Code explanations and solutions for Chapter 9 Companion: Code, Explanations and Solutions. - [Chapter 10 Companion: Code, Explanations and Solutions](/ood-agile-book/companion/chapter-10/): Code explanations and solutions for Chapter 10 Companion: Code, Explanations and Solutions. - [Chapter 11 Companion: Code, Explanations and Solutions](/ood-agile-book/companion/chapter-11/): Code explanations and solutions for Chapter 11 Companion: Code, Explanations and Solutions. - [Chapter 12 Companion: Code, Explanations and Solutions](/ood-agile-book/companion/chapter-12/): Code explanations and solutions for Chapter 12 Companion: Code, Explanations and Solutions. - [Chapter 13 Companion: Code, Explanations and Solutions](/ood-agile-book/companion/chapter-13/): Code explanations and solutions for Chapter 13 Companion: Code, Explanations and Solutions. - [Chapter 14 Companion: Code, Explanations and Solutions](/ood-agile-book/companion/chapter-14/): Code explanations and solutions for Chapter 14 Companion: Code, Explanations and Solutions. - [Chapter 15 Companion: Code, Explanations and Solutions](/ood-agile-book/companion/chapter-15/): Code explanations and solutions for Chapter 15 Companion: Code, Explanations and Solutions. - [Appendix A Companion: Code, Explanations and Solutions](/ood-agile-book/companion/appendix-a/): Code explanations and solutions for Appendix A Companion: Code, Explanations and Solutions. - [Appendix B Companion: Code, Explanations and Solutions](/ood-agile-book/companion/appendix-b/): Code explanations and solutions for Appendix B Companion: Code, Explanations and Solutions. - [Appendix C Companion: Template Kit and Checker](/ood-agile-book/companion/appendix-c/): Code explanations and solutions for Appendix C Companion: Template Kit and Checker. - [Appendix F Companion: The Risk Lab](/ood-agile-book/companion/appendix-f/): Code explanations and solutions for Appendix F Companion: The Risk Lab.