Spring Framework Concepts Practice

A comprehensive collection of Spring Boot projects demonstrating core Spring concepts including dependency injection, component scanning, and bean management through progressive learning modules.

📚 Overview

This repository contains multiple Spring Boot modules designed to help developers understand and practice fundamental Spring framework concepts through hands-on examples. Each module builds upon previous concepts, creating a structured learning path.

🏗️ Modules

FirstSpring

• Focus: Basic Spring Boot setup and component scanning
• Concepts: @Component annotation, bean registration, Spring container basics
• Entity: Student class with Spring-managed beans
• Learning Outcome: Understand how Spring discovers and manages beans

SecondSpring

• Focus: Inter-module dependencies and Maven relationships
• Concepts: Maven dependencies, bean wiring between modules
• Entities: Student and Address with relationship mapping
• Learning Outcome: Learn dependency management in multi-module projects

ThirdSpring

• Focus: Advanced dependency injection patterns
• Concepts: Constructor injection, interface-based programming, polymorphism
• Entities: Employee with Department interface (ITDepartment, SalesDepartment)
• Learning Outcome: Master dependency injection with interfaces and implementations

Demo Projects (demo1, demo2, demo3)

• Focus: Reinforcement and practice exercises
• Concepts: Progressive complexity in dependency management
• Entities: Laptop and OS relationships with varying injection patterns
• Learning Outcome: Apply learned concepts through practical exercises

🛠️ Technology Stack

• Java: 17
• Spring Boot: 4.0.1
• Build Tool: Maven
• Core Framework: Spring Framework
• Architecture: Multi-module Maven project

🚀 Getting Started

Prerequisites

• Java 17 or higher installed
• Maven 3.6 or higher
• IDE (IntelliJ IDEA, Eclipse, or VS Code)

Quick Start

Each module is independently runnable:

# Navigate to desired module
cd FirstSpring

# Run the Spring Boot application
mvn spring-boot:run

# Or build and run
mvn clean package
java -jar target/FirstSpring-0.0.1-SNAPSHOT.jar

Build All Modules

# Build all modules from root directory
mvn clean install

# Run tests across all modules
mvn test

🎯 Learning Path

Beginner Level

1. Start with FirstSpring to understand basic Spring Boot setup
2. Learn component scanning and bean lifecycle

Intermediate Level

3. Move to SecondSpring for dependency management
4. Understand Maven multi-module projects

Advanced Level

5. Study ThirdSpring for advanced DI patterns
6. Master interface-based programming with Spring

Practice

7. Complete demo1, demo2, demo3 for reinforcement
8. Experiment with custom implementations

📁 Project Structure

spring-concepts-practice/
├── FirstSpring/          # Entry point - Basic Spring concepts
├── SecondSpring/         # Step 2 - Dependency management
├── ThirdSpring/          # Step 3 - Advanced DI patterns
├── demo1/               # Practice - Basic relationships
├── demo2/               # Practice - Complex dependencies
├── demo3/               # Practice - Custom implementations
└── README.md            # This file

🔍 Key Concepts Covered

• Dependency Injection: Constructor and field injection
• Component Scanning: Automatic bean discovery
• Bean Lifecycle: Creation, initialization, and destruction
• Interface Programming: Abstraction and polymorphism
• Multi-module Projects: Maven project organization
• Spring Boot Configuration: Application properties and auto-configuration

💡 Usage Tips

• Run modules in sequence for optimal learning
• Examine the source code to understand annotations
• Use IDE debugging to trace bean creation
• Modify entities to experiment with different configurations
• Check Spring Boot logs for bean registration details

🤝 Contributing

This is a learning repository. Feel free to:

• Use the code for educational purposes
• Modify examples to experiment with Spring concepts
• Suggest improvements through issues
• Add new practice modules following the established pattern

Note: This repository is designed for educational purposes to help developers learn Spring Framework concepts progressively.