What is the start point spring application?

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1

In Spring Boot applications, the starting point is typically a main class annotated with @SpringBootApplication. This class contains the main method, which serves as the entry point for the Spring application.

Example

Here’s a simple example of a Spring Boot application’s entry point:

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication  

public class MySpringBootApplication {

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


}

Explanation:

@SpringBootApplication Annotation

  • The @SpringBootApplication annotation is a convenience annotation that combines three annotations:
    • @EnableAutoConfiguration: Enables Spring Boot’s auto-configuration mechanism.
    • @ComponentScan: Enables component scanning, allowing Spring to find and register beans within the application context.
    • @Configuration: Designates the class as a source of bean definitions.

The Main Method

  • The main method in the Spring Boot application class calls SpringApplication.run(), which launches the application. This method sets up the Spring application context, performs class path scans, starts the embedded server (if it's a web application), and initializes all the beans.
  • @SpringBootApplication: This annotation indicates that this is the main Spring Boot application class. It enables auto-configuration, component scanning, and allows defining extra beans or import other configuration classes.
  • main method: This method uses SpringApplication.run() to launch the application. The run method sets up the application context, starts the embedded server (if needed), and initializes all components.