Objective

Understand Spring Boot, a framework that simplifies Spring application development by providing auto-configuration, embedded servers, and a simplified setup process. Learn to build and deploy web applications using Spring Boot with Thymeleaf as the view technology, focusing on CRUD operations with static data (no database for this session).

Lecture Topics

1. Spring Boot Essentials

• Definition: Spring Boot is an extension of the Spring Framework that simplifies the development, configuration, and deployment of Spring-based applications.
• Core Features:
  • Auto-Configuration: Automatically configures beans and settings based on dependencies (e.g., auto-configures a DataSource if a database driver is present).
  • Embedded Servers: Includes built-in servers (e.g., Tomcat, Jetty) for standalone deployment.
  • Starter Dependencies: Pre-configured Maven/Gradle dependencies (e.g., spring-boot-starter-web).
  • Spring Boot CLI: Command-line tool for rapid prototyping.
  • Actuator: Provides production-ready features like monitoring and metrics.
• Key Annotations:
  • @SpringBootApplication: Combines @Configuration, @EnableAutoConfiguration, and @ComponentScan.
  • @RestController, @GetMapping, @PostMapping: For building RESTful APIs.
• Benefits:
  • Reduces boilerplate code (e.g., no need for web.xml).
  • Simplifies dependency management.
  • Enables rapid development and deployment.

2. Why Spring Boot

• Problems with Traditional Spring:
  • Complex XML or Java configuration for beans, MVC, and datasources.
  • Manual setup of Servlet containers (e.g., Tomcat configuration).
  • Dependency management challenges (version conflicts).
• Spring Boot Solutions:
  • Auto-configuration eliminates manual setup for common tasks.
  • Embedded servers (Tomcat, Jetty) allow running applications as standalone JARs.
  • Starter dependencies ensure compatible library versions.
  • Simplified configuration via application.properties or application.yml.
• Use Cases:
  • Rapid development of web applications, microservices, and REST APIs.
  • Simplifying enterprise application development.

3. Spring Boot Overview

• Architecture:

  • Built on top of Spring Framework.
  • Core components: Spring Boot Starters, Auto-Configuration, Embedded Server, Actuator.

• Key Files:

  • Application Class: Main class with @SpringBootApplication.

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

  • application.properties: Configures application settings (e.g., server port, logging).

    server.port=8080
    spring.thymeleaf.prefix=classpath:/templates/
    
    

• Starters:

  • Pre-configured dependencies for specific use cases.
  • Examples:
    • spring-boot-starter-web: For Spring MVC and embedded Tomcat.
    • spring-boot-starter-thymeleaf: For Thymeleaf templates.
    • spring-boot-starter-data-jpa: For Hibernate and JPA (covered in later sessions).

4. Basic Introduction of Maven

• Definition: Maven is a build automation tool for managing dependencies, building, and deploying Java projects.
• Key Concepts:
  • POM (Project Object Model): pom.xml defines project metadata, dependencies, and build settings.
  • Dependencies: Declared in pom.xml to include libraries.
  • Plugins: Extend Maven functionality (e.g., spring-boot-maven-plugin for running Spring Boot apps).
  • Lifecycle: Phases like compile, test, package, install, deploy.