Spring Boot Job Application

A Spring Boot REST API for managing Companies, Jobs, and Reviews, backed by PostgreSQL and fully Dockerized using docker-compose.

This project demonstrates:

• RESTful API design
• Spring Boot + Spring Data JPA
• Entity relationships (One-to-Many, Many-to-One)
• PostgreSQL integration
• Docker & Docker Compose setup
• Clean layered architecture (Controller → Service → Repository)

🏗️ Project Structure

SpringBootJobApplicationApp
├── src
│   ├── main
│   │   ├── java/com/springboot/jobapp
│   │   │   ├── company
│   │   │   │   ├── impl
│   │   │   │   │   └── CompanyServiceImpl.java
│   │   │   │   ├── Company.java
│   │   │   │   ├── CompanyController.java
│   │   │   │   ├── CompanyRepository.java
│   │   │   │   └── CompanyService.java
│   │   │   ├── job
│   │   │   │   ├── impl
│   │   │   │   │   └── JobServiceImpl.java
│   │   │   │   ├── Job.java
│   │   │   │   ├── JobController.java
│   │   │   │   ├── JobRepository.java
│   │   │   │   └── JobService.java
│   │   │   ├── review
│   │   │   │   ├── impl
│   │   │   │   │   └── ReviewServiceImpl.java
│   │   │   │   ├── Review.java
│   │   │   │   ├── ReviewController.java
│   │   │   │   ├── ReviewRepository.java
│   │   │   │   └── ReviewService.java
│   │   │   └── JobappApplication.java
│   │   └── resources
│   │       └── application.properties
├── docker-compose.yaml
├── pom.xml
├── mvnw
├── mvnw.cmd
└── README.md

🧠 Domain Model

Company

One Company can have:

• Many Jobs
• Many Reviews

Job

Each Job belongs to one Company

Review

Each Review belongs to one Company

Entity relationships are managed using JPA annotations.

⚙️ Technologies Used

• Java 21
• Spring Boot
• Spring Web
• Spring Data JPA
• PostgreSQL
• Hibernate
• Docker & Docker Compose
• Maven

🚀 Running the Application (Docker)

1️⃣ Prerequisites

Make sure you have:

• Docker
• Docker Compose

2️⃣ Environment Variables

Create a .env file in the project root:

POSTGRES_USER=postgres
POSTGRES_PASSWORD=postgres
POSTGRES_DB=jobappdb

3️⃣ Start Containers

docker-compose up -d

This will start:

• PostgreSQL
• pgAdmin
• Spring Boot Job Application

4️⃣ Access Services

Service	URL
Spring Boot API	http://localhost:8080
pgAdmin	http://localhost:5050
PostgreSQL	localhost:5432

🛠️ API Endpoints

🏢 Company APIs

Method	Endpoint	Description
GET	/companies	Get all companies
GET	/companies/{id}	Get company by ID
POST	/companies	Create a company
PUT	/companies/{id}	Update a company
DELETE	/companies/{id}	Delete a company

Create Company

POST /companies

{
  "name": "Google",
  "description": "Tech Company"
}

💼 Job APIs

Method	Endpoint	Description
GET	/jobs	Get all jobs
GET	/jobs/{id}	Get job by ID
POST	/jobs	Create a job
PUT	/jobs/{id}	Update a job
DELETE	/jobs/{id}	Delete a job

Create Job

POST /jobs

{
  "title": "Backend Developer",
  "description": "Spring Boot Developer",
  "minSalary": "80000",
  "maxSalary": "120000",
  "location": "Remote"
}

⭐ Review APIs

Method	Endpoint	Description
GET	/companies/{companyId}/reviews	Get all reviews
GET	/companies/{companyId}/reviews/{reviewId}	Get review
POST	/companies/{companyId}/reviews	Add review
PUT	/companies/{companyId}/reviews/{reviewId}	Update review
DELETE	/companies/{companyId}/reviews/{reviewId}	Delete review

Add Review

POST /companies/1/reviews

{
  "title": "Great Place",
  "description": "Amazing work culture",
  "rating": 4.5
}

📘 API Documentation (Swagger / OpenAPI)

This project uses Springdoc OpenAPI to provide interactive API documentation via Swagger UI.

Swagger automatically generates API documentation from the Spring Boot controllers and allows testing endpoints directly from the browser.

🔗 Swagger UI

Once the application is running, access Swagger UI at:

http://localhost:8080/swagger-ui/index.html

✨ Features

• View all available REST endpoints
• Test API requests (GET, POST, PUT, DELETE) directly from the UI
• Inspect request/response schemas and HTTP status codes
• OpenAPI 3.0 compliant documentation

🛠 Implementation Details

• Spring Boot 3.x
• springdoc-openapi-starter-webmvc-ui
• Custom OpenAPI configuration for project metadata (title, description, version)

🧩 Architecture

Controller
    ↓
Service
    ↓
Repository
    ↓
Database (PostgreSQL)

• Controller → Handles HTTP requests
• Service → Business logic
• Repository → Database access
• Entity → JPA mapped objects

🐳 Docker Services

PostgreSQL

• Image: postgres:latest
• Port: 5432

pgAdmin

• Image: dpage/pgadmin4
• Port: 5050

Spring Boot App

• Built locally using Dockerfile
• Port: 8080

📌 Notes

• spring.jpa.hibernate.ddl-auto=update automatically updates DB schema
• Circular references avoided using @JsonIgnore
• Constructor-based dependency injection is used
• REST API follows standard HTTP status codes