打开demo的pom.xml

引入依赖parent

 <!-- SpringBoot的父级依赖，引入以后，代表当前项目为SpringBoot项目，再引入它内部提供的其他的一些依赖的时候，version可以不填-->
<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>2.1.5.RELEASE</version>
    <relativePath />
</parent>

设置资源属性

<properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
    <java.version>1.8</java.version>
</properties>

引入依赖dependency

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter</artifactId>

        <!--排除Spring Boot默认使用的Log日志-->
        <exclusions>
            <exclusion>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-logging</artifactId>
            </exclusion>
        </exclusions>
    </dependency>
    <!--Spring Boot容器中包含的Web模块-->
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    <!--Spring Boot默认解析的配置文件为yml，需要解析其他格式如xml时，需要配置此依赖-->
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-configuration-processor</artifactId>
        <optional>true</optional>
    </dependency>
</dependencies>

打开demo-api下resource，创建application.yml文件，同时创建SpringBoot启动文件Application

在Application中添加注解@SpringBootApplication

package com.demo;

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

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

创建helloWord

import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class HelloController {

    @GetMapping("/hello")
    public Object hello() {
        return "hello world";
    }
}

访问 localhost:8080/hello

完成