Introduction to Spring Framework

@Configuration
@ComponentScan(basePackages = "com.example")
public class AppConfig {
}

import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;

@Configuration
@ComponentScan(basePackages = "com.example")
class AppConfig {
}

class HelloService {
  public void sayHello() {
    System.out.println("Hello from Spring Framework");
  }
}

public class Main {

  public static void main(String[] args) {

    ApplicationContext context = new AnnotationConfigApplicationContext(AppConfig.class);

    HelloService service = context.getBean(HelloService.class);

    service.sayHello();

  }
}

// Output:
// Hello from Spring Framework

• 1 A lightweight Java framework.
• 2 Used for enterprise applications.
• 3 Provides dependency injection.
• 4 Supports web and microservices development.

• 1 Dependency Injection (DI).
• 2 Aspect-Oriented Programming (AOP).
• 3 Spring MVC for web apps.
• 4 Transaction management.

• 1 Reduces boilerplate code.
• 2 Improves scalability.
• 3 Supports modular development.
• 4 Highly flexible and extensible.

• 1 Spring Boot – rapid development.
• 2 Spring MVC – web framework.
• 3 Spring Data – database access.
• 4 Spring Security – authentication & authorization.