从零开始学springboot笔记（一）-Spring boot之Hello Word

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:EcliseMyWorkPlacespringboot-hello	argetclasses started by Administrator in E:EcliseMyWorkPlacespringboot-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: default
2019-05-27 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 Tomcat
2019-05-27 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 WebApplicationContext
2019-05-27 15:27:54.180  INFO 2020 --- [ost-startStop-1] o.s.web.context.ContextLoader            : Root WebApplicationContext: initialization completed in 1198 ms
2019-05-27 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 startup
2019-05-27 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