SpringBoot2.0.2 不使用parent作为maven单继承方式操作 : org.springframework.boot : spring-boot-dependencies : 2.0.2.RELEASE

1、pom配置方式

 <?xml version="1.0" encoding="UTF-8"?>
 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
     <modelVersion>4.0.0</modelVersion>

     <groupId>com.springboot</groupId>
     <artifactId>quick_start</artifactId>
     <version>0.0.1-SNAPSHOT</version>
     <packaging>jar</packaging>

     <name>quick_start</name>
     <url>http://maven.apache.org</url>
     <description>Demo project for Spring Boot</description>

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

     <dependencies>
         <!--不使用parent方式进行依赖,需要scope和type设置-->
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-dependencies</artifactId>
             <version>2.0.2.RELEASE</version>
             <scope>import</scope>
             <type>pom</type>
         </dependency>

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

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

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

 </project>

2、实体类编写

 package com.springboot;

 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
 import org.springframework.context.ConfigurableApplicationContext;
 import org.springframework.context.annotation.Bean;

 /******************************
  * @Author : liuyang
  * @ClassName : QuickStartApplication
  * @Date : 2018 五月  20
  * @Time : 01:05:59
  * @Type : SpringBoot
  * @Version : 1.0
  * @Return :
  * @Description :
  *******************************/

 @SpringBootApplication
 public class QuickStartApplication {

     @Bean
     public Runnable createRunnable() {

         return () -> {
             System.out.println("Spring Boot is Run");
         };

     }

     public static void main(String[] args) {
         ConfigurableApplicationContext applicationContext = SpringApplication.run(QuickStartApplication.class,args);
         applicationContext.getBean(Runnable.class).run();
     }
 }

源码存放：
      需要将parent部分注释掉
        https://github.com/liushaoye/quick_start

这个在官方文档上也有具体写:

https://docs.spring.io/spring-boot/docs/2.0.2.RELEASE/reference/htmlsingle/#boot-documentation

仔细阅读这一段就是具体解答