DemoApplication.java：

package com.example.demo;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@SpringBootApplication
@RestController
public class DemoApplication {

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

   @RequestMapping("/")
    String index(){
       return "這是第一個Spring Boot工程！";
    }

}

 

有3種方式運行

1、直接運行主程序

2、根目錄下面mvn spring-boot:run

3、根目錄下面mvn install打成jar包

java -jar demo-0.0.1-SNAPSHOT.jar

訪問

http://localhost:8080/

IDEA創建Spring Boot項目