springboot的HelloWorld

    <!-- Inherit defaults from Spring Boot -->
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.13.RELEASE</version>
    </parent>

    <!-- Add typical dependencies for a web application -->
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
    </dependencies>

package xu;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

/**
 * @SpringBootApplication 来标注一个主程序类，说明这是一个Spring Boot应用
 */
@SpringBootApplication
public class HelloWorldMainApplication {
    public static void main(String[] args) {
        //spring应用启动起来
        SpringApplication.run(HelloWorldMainApplication.class,args);
    }
}

package xu.controller;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;

/**
 * @Controller 处理请求
 */
@Controller
public class
HelloController {
    /**
     * 接收来自浏览器的hello请求
     * @return
     */
    @ResponseBody
    @RequestMapping("/hello")
    public String hello(){
        return "HelloWorld!";
    }
}