Spring Booot 1
Key Concepts of Spring Boot
Convention over Configuration: Spring Boot promotes the concept of “convention over configuration,” meaning it provides sensible defaults for many settings, reducing the amount of boilerplate configuration. It uses auto-configuration to set up components based on the libraries available on the classpath.
Standalone Applications: Spring Boot allows developers to create standalone, production-ready Spring applications that can be run as a simple Java application or deployed in a container. You can package the application as an executable JAR with an embedded server (like Tomcat, Jetty, or Undertow).
Embedded Servers: Instead of deploying the application to an external application server, Spring Boot packages the server (e.g., Tomcat) inside the application. This simplifies deployment and reduces the complexity of managing servers.
Auto-Configuration: Spring Boot’s auto-configuration feature simplifies the setup of a Spring application. It automatically configures Spring components (like data sources, JPA, security, etc.) based on the libraries available in the project and some basic application properties.
Spring Boot Starter Dependencies: Spring Boot provides “starter” dependencies, which are curated sets of libraries to quickly bootstrap a project. These starters include commonly used libraries for specific functionality. For example:
spring-boot-starter-web (for web applications)
spring-boot-starter-data-jpa (for JPA and database access)
spring-boot-starter-security (for Spring Security)
Spring Boot Annotations: Spring Boot heavily relies on annotations to configure and wire components together, reducing XML configuration. Common Spring Boot annotations include @SpringBootApplication, @RestController, @RequestMapping, etc.
Spring Boot CLI: Spring Boot provides a command-line interface (CLI) to quickly prototype and run Spring applications with minimal code. You can write Groovy scripts to run Spring Boot applications directly.
Externalized Configuration: Spring Boot applications support external configuration through properties or YAML files, environment variables, and command-line arguments. This allows developers to easily manage environment-specific configurations.
The main configuration files are application.properties or application.yml.
You can also use profiles (e.g., application-dev.properties, application-prod.yml) to handle different environments.
Production-Ready Features: Spring Boot comes with several production-ready features that are helpful for monitoring and managing the application: