Artefact Three

Contact Service CRUD - Algorithms and Data Structures (Java + JUnit)

This artifact is a console-based application developed in Java that manages a contact list using JUnit tests. The original version used an "ArrayList", but it was enhanced by replacing it with a "HashMap" to achieve O(1) search efficiency. A simple text-based user interface was also integrated to simulate a real usage scenario.

I selected this artifact because it showcases my ability to optimize data structures, apply efficient design principles, and implement automated testing. The use of a "HashMap" demonstrates an understanding of algorithmic performance, while the inclusion of JUnit testing reflects professional practices for ensuring code quality. The addition of a user-facing console interface provides a realistic environment for testing the application's behavior under actual usage.

During the enhancement process, I gained a deeper understanding of the differences between linear and non-linear data structures, and the importance of selecting the appropriate structure for a given use case. I learned to write effective JUnit tests, refactor methods for better maintainability, and document each component of the code. One of the main challenges was implementing clear input validation and robust exception handling to ensure a reliable user experience.