301-frameworks-spring-boot-core

Spring Boot Core

Spring Boot Core guidelines focus on proper usage of main annotations, bean management, and configuration best practices to build maintainable and efficient Spring Boot applications.

Implementing These Principles

These guidelines are built upon the following core principles:

• Principle 1: Use appropriate Spring annotations to clearly express component responsibilities
• Principle 2: Leverage Spring's dependency injection and IoC container effectively
• Principle 3: Follow configuration best practices for maintainable and testable applications
• Principle 4: Apply proper bean lifecycle management and scoping

Table of contents

• Rule 0: Spring Boot Main Application Class
• Rule 1: Main Spring Boot Annotations Usage
• Rule 2: Bean Definition and Management
• Rule 3: Configuration Classes and Properties
• Rule 4: Component Scanning and Package Organization
• Rule 5: Conditional Configuration and Profiles
• Rule 6: Constructor Dependency Injection Best Practices
• Rule 7: Bean Minimization and Composition
• Rule 8: Scheduled Tasks and Background Processing

Rule 0: Spring Boot Main Application Class

Title: Create a Proper Spring Boot Main Application Class Description: Every Spring Boot application should have a main application class annotated with @SpringBootApplication. This class serves as the entry point and configuration root, combining @Configuration, @EnableAutoConfiguration, and @ComponentScan annotations.

Good example:

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

// For more complex scenarios with custom configuration
@SpringBootApplication(
    scanBasePackages = {
        "com.company.app.controller",
        "com.company.app.service", 
        "com.company.app.repository",
        "com.company.app.config"
    },
    exclude = {
        DataSourceAutoConfiguration.class,
        SecurityAutoConfiguration.class
    }
)