why spring-boot application doesn't require @EnableWebMvc

Question

So i wrote a small application, In order to get familiar with basics i made it as simple as possible. I made a simple mvc application with Config.java file and when i thought that now the application should throw an error it actually works.

Here's my pom.xml

<?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"     xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">     <modelVersion>4.0.0</modelVersion>      <groupId>com.example</groupId>     <artifactId>demo</artifactId>     <version>0.0.1-SNAPSHOT</version>     <packaging>jar</packaging>      <name>demo</name>     <description>Demo project for Spring Boot</description>      <parent>         <groupId>org.springframework.boot</groupId>         <artifactId>spring-boot-starter-parent</artifactId>         <version>2.0.3.RELEASE</version>         <relativePath/> <!-- lookup parent from repository -->     </parent>      <properties>         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>         <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>         <java.version>1.8</java.version>     </properties>      <dependencies>         <dependency>             <groupId>org.springframework.boot</groupId>             <artifactId>spring-boot-starter</artifactId>         </dependency>          <dependency>             <groupId>org.springframework.boot</groupId>             <artifactId>spring-boot-starter-test</artifactId>             <scope>test</scope>         </dependency>          <dependency>             <groupId>org.springframework.boot</groupId>             <artifactId>spring-boot-starter-thymeleaf</artifactId>         </dependency>          <dependency>     <groupId>org.springframework.boot</groupId>     <artifactId>spring-boot-starter-web</artifactId> </dependency>     </dependencies>     <build>         <plugins>             <plugin>                 <groupId>org.springframework.boot</groupId>                 <artifactId>spring-boot-maven-plugin</artifactId>             </plugin>         </plugins>     </build> 

My Config file which only has a view resolver:

package com.example.demo;  import org.springframework.context.annotation.Bean;  import org.springframework.context.annotation.Configuration; import org.springframework.web.servlet.ViewResolver;  import org.springframework.web.servlet.view.InternalResourceViewResolver; import org.springframework.web.servlet.view.JstlView;   @Configuration public class DemoConfig {      @Bean     public ViewResolver internalResourceViewResolver() {         InternalResourceViewResolver bean = new InternalResourceViewResolver();         bean.setViewClass(JstlView.class);         bean.setPrefix("/templates/");         bean.setSuffix(".html");         return bean;     } } 

Main file

package com.example.demo;  import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication;  @SpringBootApplication public class DemoApplication {      public static void main(String[] args) {         SpringApplication.run(DemoApplication.class, args);     } } 

And finally the controller class : package com.example.demo.controller;

import org.springframework.stereotype.Controller; import org.springframework.web.bind.annotation.GetMapping;  @Controller public class TestController {     @GetMapping(value="home")     public String home() {         return "home";     } } 

Application.properties

server.servlet.context-path=/demo 

So this is the entire application , as i can recall i require mvc:annotation- driven in web.xml or @enablewebmvc for getting @getmapping and @controller to work but my application works completely . How is it not throwing an error ?

Answer 1

@SpringBootApplication is a convenience annotation that adds all of the following:

• @Configuration tags the class as a source of bean definitions for the application context.
• @EnableAutoConfiguration tells Spring Boot to start adding beans based on classpath settings, other beans, and various property settings.
• Normally you would add @EnableWebMvc for a Spring MVC app, but Spring Boot adds it automatically when it sees spring-webmvc on the classpath. This flags the application as a web application and activates key behaviors such as setting up a DispatcherServlet.
• @ComponentScan tells Spring to look for other components, configurations, and services in the hello package, allowing it to find the controllers.