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Creating a Spring Boot Web Project

This guide walks you through building a simple Spring Boot web application using the MVC architecture. You will learn how to set up the project, create controllers, views, and handle web requests.

1. What You Need Before Starting

Install the following:

  • Java 8+ (preferably 17 or 21)
  • IDE (IntelliJ / STS / Eclipse)
  • Maven or Gradle (Maven considered here)
  • Web browser

Confirm Java:

java -version

2. Create Spring Boot Project (Spring Initializr)

Option 1 — Using Website (Recommended)

Go to:

https://start.spring.io

Fill form:

  • Project: Maven

  • Language: Java

  • Spring Boot Version: stable latest

  • Project Metadata

    • Group: com.example
    • Artifact: springboot-demo
    • Packaging: Jar

  • Java Version: 17 (or your LTS version)

Add Dependencies

Select:

  • Spring Web
  • Thymeleaf (for web pages support)

Click Generate, download the ZIP → extract → open in IDE.

3. Understanding Project Structure

src/
 └── main/
      ├── java/
      │    └── com.example.demo/
      │          ├── DemoApplication.java
      │          └── controller/
      │                └── HomeController.java
      └── resources/
           ├── static/
           │     ├── css/
           │     └── js/
           ├── templates/
           │     └── home.html
           └── application.properties

Meaning of folders:

  • templates/ → HTML (Thymeleaf Views)
  • static/ → CSS, JavaScript, images
  • application.properties → configuration
  • controller/ → controller classes
  • DemoApplication.java → main entry point

4. The Main Spring Boot Application Class

DemoApplication.java is auto-generated:

@SpringBootApplication
public class DemoApplication {
    public static void main(String[] args) {
        SpringApplication.run(DemoApplication.class, args);
    }
}

Explanation:

  • @SpringBootApplication enables:

    • component scanning
    • auto-configuration
    • configuration properties

  • SpringApplication.run() starts:

    • Spring Context
    • Embedded Tomcat server
    • DispatcherServlet

Default app runs on port 8080

5. Add a Controller (Handles Web Requests)

Create package:

com.example.demo.controller

Create file:

@Controller
public class HomeController {

    @GetMapping("/")
    public String homePage(Model model) {
        model.addAttribute("title", "Spring Boot Web Project");
        model.addAttribute("message", "Welcome! This is your first Spring Boot web page.");
        return "home";
    }
}

What this does

  • @Controller → marks as MVC controller
  • @GetMapping("/") → maps root URL
  • Model → carries data to view
  • returns view name → home

6. Create Web Page (View Layer)

Go to:

src/main/resources/templates/

Create file:

home.html

Add code:

<!DOCTYPE html>
<html xmlns:th="http://www.thymeleaf.org">
<head>
    <title th:text="${title}">Home</title>
</head>
<body>
    <h1 th:text="${message}"></h1>
    <p>This page is rendered using Spring Boot + Thymeleaf MVC.</p>
</body>
</html>

Spring automatically uses Thymeleaf to render this.

No JSP needed.

7. Run the Project

Using IDE

Run DemoApplication.java

Or Terminal

mvn spring-boot:run

Open in browser:

http://localhost:8080/

You will see your webpage rendered 🎯

8. Adding More Controller Mappings

Path Variable

@GetMapping("/user/{name}")
public String greetUser(@PathVariable String name, Model model) {
    model.addAttribute("message", "Hello " + name);
    return "home";
}

URL:

/user/Ben

Request Parameter

@GetMapping("/search")
public String search(@RequestParam String query, Model model) {
    model.addAttribute("message", "Searching for: " + query);
    return "home";
}

URL:

/search?query=java

9. POST Request Example (Form Submission)

Step 1 — Add HTML Form

Add to home.html:

<form action="/submit" method="post">
    <input type="text" name="name" placeholder="Enter Name">
    <button type="submit">Submit</button>
</form>

Step 2 — Controller Method

@PostMapping("/submit")
public String submit(@RequestParam String name, Model model) {
    model.addAttribute("message", "Form submitted by: " + name);
    return "home";
}

This handles form submissions gracefully.

10. Servlet & DispatcherServlet Behind the Scenes

Spring Boot internally:

  • configures DispatcherServlet
  • registers it in embedded Tomcat
  • routes every incoming HTTP request through it

Flow:

Browser request
      ↓
DispatcherServlet
      ↓
HandlerMapping
      ↓
Controller method
      ↓
Returns Model + View
      ↓
ViewResolver selects template
      ↓
HTML generated → Browser

11. application.properties Configurations (Important)

Located at:

src/main/resources/application.properties

Change Server Port

server.port=9090

Disable Whitelabel Error Page

server.error.whitelabel.enabled=false

Set application name

spring.application.name=SpringBootWebApp

12. Static Resources Handling

Place:

  • CSS → static/css
  • JS → static/js
  • images → static/images

Spring Boot serves them automatically.

Example:

<link rel="stylesheet" href="/css/style.css">

13. Directory Structure Summary

controllers   → handle HTTP requests
models        → hold data
services      → business logic
repositories  → DB operations (later with JPA)
templates     → HTML UI
static        → CSS/JS/images

14. Common Errors & Fixes

Issue Fix
Port already in use Stop previous server or change port
Template not found check /templates/filename.html
Whitelabel Error Page invalid controller or mapping
404 Not Found mapping incorrect
Method Not Allowed using wrong HTTP method

Key Takeaways

  • Spring Boot simplifies web app creation

  • MVC = Model + View + Controller

  • DispatcherServlet handles routing

  • Thymeleaf used for UI rendering

  • Minimal configuration required

  • Embedded server handles HTTP