Spring Automated Component Scanning

This project demonstrates the Annotation-Based Configuration method using Spring's Component Scanning capabilities. This is the most modern and common way to handle Dependency Injection in Spring Boot.

Key Features

• Auto-Detection: Using @ComponentScan to find beans automatically.
• Stereotype Annotations: Marking classes with @Component to register them in the IoC container.
• Auto-wiring: Using @Autowired to inject dependencies without manual setters or constructors.
• Ambiguity Handling:
  • @Primary: Defines a default bean implementation.
  • @Qualifier: Allows specific selection between multiple implementations (Jio vs Airtel).

Project Evolution

This repo represents the 3rd stage of Spring learning:

1. XML-Based (Manual)
2. Java-Based (Semi-Manual)
3. Component Scanning (Fully Automated) - Now are here

How it Works

Spring scans the package org.spring.dependencyinjection.automatedcomponent.scanmethod.

1. It finds Jio and Airtel and creates beans named jioBean and airtelBean.
2. It finds the Mobile class and sees it is also a @Component.
3. It "wires" the Sim dependency into Mobile using the ID provided in @Qualifier.

Sample Output

Jio Calling
Jio Data

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Comparison of @Primary vs @Qualifier

Here is why your output will specifically show "Jio":

Feature	What it does	Your Code
@Primary	The "Default" choice.	Set on Airtel.
@Qualifier	The "Specific" choice.	Set on Mobile (points to Jio).
Winner	Qualifier always wins.	Jio is printed.

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