SpringBoot入门编写第一个程序Helloworld

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>2.3.4.RELEASE</version>
</parent>
<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-WEB</artifactId>
    </dependency>

</dependencies>

@SpringBootApplication
public class MainApplication {

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

@RestController
public class HelloController {

    @RequestMapping("/hello")
    public String handle01(){
        return "Hello, Spring Boot 2!";
    }

}

<build>
    <plugins>
        <plugin>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-maven-plugin</artifactId>
        </plugin>
    </plugins>
</build>