Cognizant GenC — Java FSE

I'm a final-year Computer Science student. My most proud project was a Spring Boot inventory management system where I designed the REST API and integrated it with PostgreSQL. I handled 50,000+ records and optimized queries to reduce latency by 40%. The system is used by 5 small retailers locally.

Collections are interfaces and classes in java.util for storing groups of objects. HashMap is a hash table that provides O(1) average lookup but doesn't maintain insertion order. LinkedHashMap maintains insertion order by using a doubly linked list. I'd use HashMap for caches where order doesn't matter and LinkedHashMap when I need to preserve insertion order like in LRU caches.

Spring is a lightweight framework that provides dependency injection and simplifies enterprise Java development. Key annotations I use: @SpringBootApplication for the entry point, @RestController for REST endpoints, @Service for business logic, @Autowired for dependency injection, @GetMapping/@PostMapping for HTTP methods. Spring Boot auto-configures most of the setup so we focus on writing business logic.