Overview

A RESTful backend application for managing student academic records, built with Java 17 and Spring Boot following a Controller–Service–Repository architecture.

Tech Stack

Java 17 · Spring Boot · Spring Data JPA · PostgreSQL · Maven · Postman

Key Features

• CRUD APIs for student records with nested subject-wise marks
• Credit-weighted grading engine that dynamically calculates percentage and letter grade
• One-to-many JPA relationship between Student and SubjectMark
• Input validation and structured API responses
• API testing using Postman

System Architecture

Engineering Highlight

I encountered a bidirectional JSON serialization loop caused by circular Student ↔ SubjectMark references, resulting in excessively large API responses. I diagnosed the issue and fixed it using @JsonIgnore while preserving the underlying JPA relationship.

API Demo

The following screenshot shows the GET /students endpoint returning student records with dynamically calculated weighted percentage and grade.