工具：Eclipse、jdk1.8、maven；
一：先建一个maven的项目

然后再pom文件中添加相关依赖和配置，具体如下： <!-- spring boot 父节点依赖,引入这个之后相关的引入就不需要添加version配置，spring boot会自动选择最合适的版本进行添加。--><parent><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-parent</artifactId><version>1.4.1.RELEASE</version></parent><properties><project.build.sourceEncoding>UTF-8</project.build.sourceEncoding><java.version>1.8</java.version></properties><dependencies><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency></dependencies>

注意添加依赖后，记得update；

然后创建HelloController，code如下：
import java.util.Date;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.RestController;@RestController
public class HelloController {@RequestMapping("/hello")public String hello(){return"hello";}
}

然后编码springboot启动类App.java

@SpringBootApplication
public class App// extends WebMvcConfigurerAdapter
{public static void main( String[]args ){System.out.println("--------------开始启动---------------!" );        SpringApplication.run(App.class, args);        System.out.println( "--------------启动成功---------------!" );}
}

打开app.java,右键run as java application启动springboot应用；

--------------开始启动---------------!.   ____          _            __ _ _/\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \\\/  ___)| |_)| | | | | || (_| |  ) ) ) )'  |____| .__|_| |_|_| |_\__,| / / / /=========|_|==============|___/=/_/_/_/:: Spring Boot ::        (v1.4.1.RELEASE)2019-05-27 15:27:52.942  INFO 2020 --- [main] com.feiyun.springboot_hello.App          : Starting App on TEST-PC with PID 2020(E:\Eclise\MyWorkPlace\springboot-hello\target\classes started by Administrator in E:\Eclise\MyWorkPlace\springboot-hello)2019-05-27 15:27:52.944  INFO 2020 --- [main] com.feiyun.springboot_hello.App          : No active profile set,falling back to default profiles: default2019-05-27 15:27:52.985  INFO 2020 --- [main] ationConfigEmbeddedWebApplicationContext : Refreshing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@4b0b0854: startup date [Mon May 27 15:27:52 CST 2019];root of context hierarchy
2019-05-27 15:27:54.084  INFO 2020 --- [main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat initialized with port(s): 8080(http)2019-05-27 15:27:54.097  INFO 2020 --- [main]o.apache.catalina.core.StandardService   : Starting service Tomcat2019-05-27 15:27:54.099  INFO 2020 --- [main] org.apache.catalina.core.StandardEngine  : Starting Servlet Engine: Apache Tomcat/8.5.5
2019-05-27 15:27:54.180  INFO 2020 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/]: Initializing Spring embedded WebApplicationContext2019-05-27 15:27:54.180  INFO 2020 --- [ost-startStop-1] o.s.web.context.ContextLoader            : Root WebApplicationContext: initialization completed in 1198ms2019-05-27 15:27:54.327  INFO 2020 --- [ost-startStop-1] o.s.b.w.servlet.ServletRegistrationBean  : Mapping servlet: 'dispatcherServlet' to [/]
2019-05-27 15:27:54.331  INFO 2020 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'characterEncodingFilter' to: [/*]
2019-05-27 15:27:54.331  INFO 2020 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'hiddenHttpMethodFilter' to: [/*]
2019-05-27 15:27:54.331  INFO 2020 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'httpPutFormContentFilter' to: [/*]
2019-05-27 15:27:54.332  INFO 2020 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'requestContextFilter' to: [/*]
2019-05-27 15:27:54.592  INFO 2020 --- [main] s.w.s.m.m.a.RequestMappingHandlerAdapter : Looking for @ControllerAdvice: org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@4b0b0854: startup date [Mon May 27 15:27:52 CST 2019];root of context hierarchy
2019-05-27 15:27:54.647  INFO 2020 --- [main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/hello]}"onto public java.lang.String com.feiyun.springboot_hello.HelloController.hello()2019-05-27 15:27:54.648  INFO 2020 --- [main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/getDemo]}"onto public com.feiyun.springboot_hello.Demo com.feiyun.springboot_hello.HelloController.getDemo()2019-05-27 15:27:54.652  INFO 2020 --- [main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error]}" onto public org.springframework.http.ResponseEntity<java.util.Map<java.lang.String,java.lang.Object>> org.springframework.boot.autoconfigure.web.BasicErrorController.error(javax.servlet.http.HttpServletRequest)2019-05-27 15:27:54.652  INFO 2020 --- [main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/error],produces=[text/html]}" onto public org.springframework.web.servlet.ModelAndView org.springframework.boot.autoconfigure.web.BasicErrorController.errorHtml(javax.servlet.http.HttpServletRequest,javax.servlet.http.HttpServletResponse)2019-05-27 15:27:54.674  INFO 2020 --- [main] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/webjars/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2019-05-27 15:27:54.674  INFO 2020 --- [main] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2019-05-27 15:27:54.706  INFO 2020 --- [main] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/**/favicon.ico] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2019-05-27 15:27:54.825  INFO 2020 --- [main]o.s.j.e.a.AnnotationMBeanExporter        : Registering beans for JMX exposure on startup2019-05-27 15:27:54.870  INFO 2020 --- [main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat started on port(s): 8080(http)2019-05-27 15:27:54.873  INFO 2020 --- [main] com.feiyun.springboot_hello.App          : Started App in 2.258 seconds (JVM running for 2.533)
--------------启动成功---------------!

运行成功后，打开浏览器访问hello方法，注意默认端口是8080；

end;

hello