Basic Java Web Server REST API

This is a basic web server project originally built with native Java, now refactored into a professional RESTful JSON API. It demonstrates fundamental backend concepts such as handling HTTP methods, thread pools for concurrency, routing, and processing JSON payloads. The goal of this project is to serve as an educational reference for building a modern web service in Java from scratch.

Features

• REST API (JSON): Fully responds and consumes application/json using Google's Gson library.
• Concurrency: Built-in ThreadPoolExecutor for handling multiple HTTP requests simultaneously.
• Maven Architecture: Standardized project structure and dependency management.
• Dev Tooling: Code automatically formatted via Spotless (Google Java Format) and linted via Checkstyle.
• CI/CD Ready: Includes GitHub Actions for PR checks (Format/Lint/Test) and multi-stage manual deployment pipelines using SCP/SSH.

Getting Started

Prerequisites

Ensure you have Java Development Kit (JDK) 17+ and Apache Maven installed on your machine.

Installation

1. Clone the repository:

   git clone https://github.com/FarrelAD/Basic-Web-Server-Java.git

2. Navigate into the project directory:

   cd Basic-Web-Server-Java

Running the Server

Using Maven, you can compile and start the server immediately:

mvn clean compile exec:java -Dexec.mainClass="com.server.Main"

The server will be running at http://localhost:8000

Building the Executable JAR

If you want to build a deployment-ready Fat JAR:

mvn clean package -DskipTests
java -jar target/basic-web-server-1.0-SNAPSHOT.jar

Tooling & Testing

Run the automated tests:

mvn test

Format the codebase and check for linting errors:

mvn spotless:apply checkstyle:check

Pre-commit Hooks

This project strictly enforces code quality using Git pre-commit hooks (Spotless and Checkstyle). After cloning the repository, you must configure Git to use the local hooks directory:

git config core.hooksPath .githooks

Every time you commit, it will automatically verify formatting and linting. If it fails, the commit will be aborted.

Endpoints

Here are the key REST endpoints you can interact with. All endpoints strictly consume and return application/json.

1. API Health Check

• GET /
  • Response (200 OK):

    {
      "status": "UP",
      "message": "Welcome to Basic Web Server API",
      "totalUsers": 8
    }

2. Fetch All Users

• GET /users
  • Response (200 OK):

    [
      { "name": "Alex", "job": "Data Analyst" },
      { "name": "Budi", "job": "Frontend Web Developer" }
    ]

3. Fetch User by ID

• GET /users/:id (e.g. /users/1)
  • Response (200 OK):

    {
      "name": "Alex",
      "job": "Data Analyst"
    }

4. Create New User

• POST /users
  • Request Body:

    {
      "name": "John Doe",
      "job": "Backend Engineer"
    }

  • Response (201 Created):

    {
      "status": "success",
      "message": "User added successfully"
    }

5. Update User Information

• PATCH /users/:id (e.g. /users/1)
  • Request Body:

    {
      "job": "Senior Data Analyst"
    }

  • Response (200 OK):

    {
      "status": "success",
      "message": "Data updated successfully"
    }

6. Delete a User

• DELETE /users/:id (e.g. /users/1)
  • Response (200 OK):

    {
      "status": "success",
      "message": "Data deleted successfully"
    }

7. Search Users

• GET /search?name=&job= (e.g. /search?job=Data Analyst)
  • Response (200 OK):

    [
      { "name": "Alex", "job": "Data Analyst" },
      { "name": "Dono", "job": "Data Analyst" }
    ]

Code Structure

The project uses the standard Maven structure:

/root
├───.github/workflows   # CI/CD Pipelines
├───pom.xml             # Build config and dependencies
└───src
    ├───main/java/com/server
    │   ├─── /controller    # HTTP route handlers
    │   ├─── /model         # Data structures and tracking
    │   ├─── /utils         # Parsers and HTTP helpers
    │   └─── Main.java      # Server initialization and Thread Pool
    └───test/java/com/server
        └─── /model         # JUnit 5 test cases

License

This project is licensed under the MIT License.

Acknowledgments

This project is intended to help others learn the basics of building a robust REST API with Java ☕.