命令行或者idea、eclipse快捷创建也可以
<parent>
<artifactId>spring-boot-starter-parentartifactId>
<groupId>org.springframework.bootgroupId>
<version>2.5.3version>
parent>
<dependencies>
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-webartifactId>
dependency>
dependencies>
package com.wujialiang.springboot01;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
/**
* spring boot启动类
*
*/
@SpringBootApplication
public class App {
public static void main(String[] args) {
// 第一个参数是该类的名字.class 第二个参数是main方法中的参数
SpringApplication.run(App.class, args);
}
}

访问loalhost:8080,因为没有其他接口所以报错

新建HelloController.java
package com.wujialiang.springboot01.controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
@RestController
public class HelloController {
@GetMapping("/")
public String hello() {
return "Hello World";
}
}
重新启动项目访问
