spring-boot 项目搭建

使用maven搭建springboot项目，有以下几种方式：

1. http://start.spring.io/

在上面网站选填项目基本信息（如：项目类型、语言、Spring Boot版本等），以及需要导入的依赖，点击“Generate Project alt + enter”生成 Spring Boot 项目的 zip 文件，下载解压导入IDE即可（选择导入maven项目）

2. 手动创建 maven 项目

“Create a simple project”勾选不勾选都可以

2.1.1勾选“Create a simple project”

填写 group id，artifact id 等信息，点击“Finish”

创建好的目录结构如上图所示，可以根据需要修改 jdk 的版本。

生成的 pom.xml 文件内容如下：

<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>cn.com.first</groupId>
  <artifactId>myfSpringBoot</artifactId>
  <version>0.0.1-SNAPSHOT</version>
</project>

2.1.2 不勾选“Create a simple project”

"next"-->

"Finish"-->

生成的pom.xml文件内容如下：

<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>cn.com.second</groupId>
  <artifactId>mysSpringBoot</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <packaging>jar</packaging>

  <name>mysSpringBoot</name>
  <url>http://maven.apache.org</url>

  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
  </properties>

  <dependencies>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>3.8.1</version>
      <scope>test</scope>
    </dependency>
  </dependencies>
</project>

2.2 修改 pom.xml 文件，引入 <parent> 元素

继承<parent>pom里面已经引入了 tomcat、jetty 等很多常用依赖

2.2.1引入“1.4.0.RELEASE”版本的<parent> 元素

<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>cn.com.first</groupId>
  <artifactId>myfSpringBoot</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  
  <parent>
	<groupId>org.springframework.boot</groupId>
	<artifactId>spring-boot-starter-parent</artifactId>
	<version>1.4.0.RELEASE</version>
	<relativePath/> <!-- lookup parent from repository -->
   </parent>
</project>

没有添加任何依赖也可以build。在项目根目录打开cmd命令行执行: mvn package 对项目进行打包。

会自动下载一堆 http://maven.aliyun.com 的 jar 到 maven 仓库，这是因为我的 setting.xml 文件配置的远程仓库是 aliyun 的远程仓库。（如下图）

项目构建成功后，我们来看一下项目 target 目录下发生的变化：

2.2.2引入“2.0.0.M3”版本的<parent> 元素

此时 pom.xml 文件会报一个 build error 的错，配置spring-milestones这个仓库即可

<repositories>
	<repository>
		<id>spring-milestones</id>
		<name>Spring Milestones</name>
		<url>https://repo.spring.io/milestone</url>
		<snapshots>
			<enabled>false</enabled>
		</snapshots>
	</repository>
</repositories>
<pluginRepositories>
	<pluginRepository>
		<id>spring-milestones</id>
		<name>Spring Milestones</name>
		<url>https://repo.spring.io/milestone</url>
		<snapshots>
			<enabled>false</enabled>
		</snapshots>
	</pluginRepository>
</pluginRepositories>

<repositories>是 jar 包库，<pluginRepositories>是插件库。

2.3 启动类（这时只是一个普通的 maven 项目）

package cn.com.second;

public class StartApplication{

  public static void main(String[] args){
    System.out.println( "Hello Spring Boot!" );
  }
}

启动StartApplication

2.4 启动  springboot 项目

package cn.com.second;

import org.springframework.boot.SpringApplication;

public class StartApplication{

  public static void main(String[] args){
    SpringApplication.run(StartApplication.class, args);//需要引入下面依赖
  }
}

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

2.4.1 添加 springboot 默认配置文件 application.properties 

2.4.2. 然后启动项目仍然不会报错，现在 controller 里面添加一个 test 方法，如下图：

此时启动类上需要添加注解 @SpringBootApplication ， 否则项目启动时会报错

  .   ____          _            __ _ _
 /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
 \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::             (v2.0.0.M3)

2018-06-15 14:55:11.159  INFO 15640 --- [           main] c.c.s.mysSpringBoot.StartApplication     : Starting StartApplication on lkk-PC with PID 15640 (F:\workspace\mysSpringBoot\target\classes started by lkk in F:\workspace\mysSpringBoot)
2018-06-15 14:55:11.162  INFO 15640 --- [           main] c.c.s.mysSpringBoot.StartApplication     : No active profile set, falling back to default profiles: default
2018-06-15 14:55:11.176  INFO 15640 --- [           main] ConfigServletWebServerApplicationContext : Refreshing org.springframework.boot.web.servlet.context.AnnotationConfigServletWebServerApplicationContext@527e5409: startup date [Fri Jun 15 14:55:11 CST 2018]; root of context hierarchy
2018-06-15 14:55:11.233  WARN 15640 --- [           main] ConfigServletWebServerApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.context.ApplicationContextException: Unable to start web server; nested exception is org.springframework.context.ApplicationContextException: Unable to start ServletWebServerApplicationContext due to missing ServletWebServerFactory bean.
2018-06-15 14:55:11.238  WARN 15640 --- [           main] o.s.b.c.e.EventPublishingRunListener     : Error calling ApplicationEventListener

java.lang.ClassCastException: org.springframework.boot.context.event.ApplicationFailedEvent cannot be cast to org.springframework.boot.web.context.WebServerInitializedEvent
	at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:159) [spring-context-5.0.0.RC3.jar:5.0.0.RC3]
	at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:139) [spring-context-5.0.0.RC3.jar:5.0.0.RC3]
	at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:127) [spring-context-5.0.0.RC3.jar:5.0.0.RC3]
	at org.springframework.boot.context.event.EventPublishingRunListener.finished(EventPublishingRunListener.java:114) [spring-boot-2.0.0.M3.jar:2.0.0.M3]
	at org.springframework.boot.SpringApplicationRunListeners.callFinishedListener(SpringApplicationRunListeners.java:79) [spring-boot-2.0.0.M3.jar:2.0.0.M3]
	at org.springframework.boot.SpringApplicationRunListeners.finished(SpringApplicationRunListeners.java:72) [spring-boot-2.0.0.M3.jar:2.0.0.M3]
	at org.springframework.boot.SpringApplication.handleRunFailure(SpringApplication.java:803) [spring-boot-2.0.0.M3.jar:2.0.0.M3]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:338) [spring-boot-2.0.0.M3.jar:2.0.0.M3]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1245) [spring-boot-2.0.0.M3.jar:2.0.0.M3]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1233) [spring-boot-2.0.0.M3.jar:2.0.0.M3]
	at cn.com.second.mysSpringBoot.StartApplication.main(StartApplication.java:9) [classes/:na]

2018-06-15 14:55:11.240 ERROR 15640 --- [           main] o.s.boot.SpringApplication               : Application startup failed

org.springframework.context.ApplicationContextException: Unable to start web server; nested exception is org.springframework.context.ApplicationContextException: Unable to start ServletWebServerApplicationContext due to missing ServletWebServerFactory bean.
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.onRefresh(ServletWebServerApplicationContext.java:137) ~[spring-boot-2.0.0.M3.jar:2.0.0.M3]
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:543) ~[spring-context-5.0.0.RC3.jar:5.0.0.RC3]
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:122) ~[spring-boot-2.0.0.M3.jar:2.0.0.M3]
	at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:750) [spring-boot-2.0.0.M3.jar:2.0.0.M3]
	at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:386) [spring-boot-2.0.0.M3.jar:2.0.0.M3]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:327) [spring-boot-2.0.0.M3.jar:2.0.0.M3]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1245) [spring-boot-2.0.0.M3.jar:2.0.0.M3]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1233) [spring-boot-2.0.0.M3.jar:2.0.0.M3]
	at cn.com.second.mysSpringBoot.StartApplication.main(StartApplication.java:9) [classes/:na]
Caused by: org.springframework.context.ApplicationContextException: Unable to start ServletWebServerApplicationContext due to missing ServletWebServerFactory bean.
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.getWebServerFactory(ServletWebServerApplicationContext.java:186) ~[spring-boot-2.0.0.M3.jar:2.0.0.M3]
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.createWebServer(ServletWebServerApplicationContext.java:160) ~[spring-boot-2.0.0.M3.jar:2.0.0.M3]
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.onRefresh(ServletWebServerApplicationContext.java:134) ~[spring-boot-2.0.0.M3.jar:2.0.0.M3]
	... 8 common frames omittedt

同时需要引入 web 依赖：

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

顺利启动：

  .   ____          _            __ _ _
 /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
 \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::             (v2.0.0.M3)

2018-06-15 15:06:10.509  INFO 14536 --- [           main] c.c.s.mysSpringBoot.StartApplication     : Starting StartApplication on lkk-PC with PID 14536 (F:\workspace\mysSpringBoot\target\classes started by lkk in F:\workspace\mysSpringBoot)
2018-06-15 15:06:10.512  INFO 14536 --- [           main] c.c.s.mysSpringBoot.StartApplication     : No active profile set, falling back to default profiles: default
2018-06-15 15:06:10.550  INFO 14536 --- [           main] ConfigServletWebServerApplicationContext : Refreshing org.springframework.boot.web.servlet.context.AnnotationConfigServletWebServerApplicationContext@527e5409: startup date [Fri Jun 15 15:06:10 CST 2018]; root of context hierarchy
2018-06-15 15:06:11.655  INFO 14536 --- [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat initialized with port(s): 8082 (http)
2018-06-15 15:06:11.667  INFO 14536 --- [           main] o.apache.catalina.core.StandardService   : Starting service [Tomcat]
2018-06-15 15:06:11.668  INFO 14536 --- [           main] org.apache.catalina.core.StandardEngine  : Starting Servlet Engine: Apache Tomcat/8.5.16
2018-06-15 15:06:11.767  INFO 14536 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext
2018-06-15 15:06:11.768  INFO 14536 --- [ost-startStop-1] o.s.web.context.ContextLoader            : Root WebApplicationContext: initialization completed in 1220 ms
2018-06-15 15:06:11.937  INFO 14536 --- [ost-startStop-1] o.s.b.w.servlet.ServletRegistrationBean  : Mapping servlet: 'dispatcherServlet' to [/]
2018-06-15 15:06:11.941  INFO 14536 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'metricsFilter' to: [/*]
2018-06-15 15:06:11.941  INFO 14536 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'characterEncodingFilter' to: [/*]
2018-06-15 15:06:11.942  INFO 14536 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'hiddenHttpMethodFilter' to: [/*]
2018-06-15 15:06:11.942  INFO 14536 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'httpPutFormContentFilter' to: [/*]
2018-06-15 15:06:11.942  INFO 14536 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'requestContextFilter' to: [/*]
2018-06-15 15:06:11.942  INFO 14536 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'webRequestLoggingFilter' to: [/*]
2018-06-15 15:06:12.289  INFO 14536 --- [           main] s.w.s.m.m.a.RequestMappingHandlerAdapter : Looking for @ControllerAdvice: org.springframework.boot.web.servlet.context.AnnotationConfigServletWebServerApplicationContext@527e5409: startup date [Fri Jun 15 15:06:10 CST 2018]; root of context hierarchy
2018-06-15 15:06:12.357  INFO 14536 --- [           main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/test]}" onto public java.lang.String cn.com.second.mysSpringBoot.controller.SecondController.test()
2018-06-15 15:06:12.364  INFO 14536 --- [           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.servlet.error.BasicErrorController.error(javax.servlet.http.HttpServletRequest)
2018-06-15 15:06:12.364  INFO 14536 --- [           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.servlet.error.BasicErrorController.errorHtml(javax.servlet.http.HttpServletRequest,javax.servlet.http.HttpServletResponse)
2018-06-15 15:06:12.391  INFO 14536 --- [           main] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/webjars/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2018-06-15 15:06:12.391  INFO 14536 --- [           main] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2018-06-15 15:06:12.426  INFO 14536 --- [           main] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/**/favicon.ico] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2018-06-15 15:06:12.628  INFO 14536 --- [           main] o.s.b.a.e.mvc.EndpointHandlerMapping     : Mapped "{[/application/beans || /application/beans.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v2+json || application/json]}" onto public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.EndpointMvcAdapter.invoke()
2018-06-15 15:06:12.630  INFO 14536 --- [           main] o.s.b.a.e.mvc.EndpointHandlerMapping     : Mapped "{[/application/loggers/{name:.*}],methods=[GET],produces=[application/vnd.spring-boot.actuator.v2+json || application/json]}" onto public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.LoggersMvcEndpoint.get(java.lang.String)
2018-06-15 15:06:12.631  INFO 14536 --- [           main] o.s.b.a.e.mvc.EndpointHandlerMapping     : Mapped "{[/application/loggers/{name:.*}],methods=[POST],consumes=[application/vnd.spring-boot.actuator.v2+json || application/json],produces=[application/vnd.spring-boot.actuator.v2+json || application/json]}" onto public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.LoggersMvcEndpoint.set(java.lang.String,java.util.Map<java.lang.String, java.lang.String>)
2018-06-15 15:06:12.631  INFO 14536 --- [           main] o.s.b.a.e.mvc.EndpointHandlerMapping     : Mapped "{[/application/loggers || /application/loggers.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v2+json || application/json]}" onto public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.EndpointMvcAdapter.invoke()
2018-06-15 15:06:12.632  INFO 14536 --- [           main] o.s.b.a.e.mvc.EndpointHandlerMapping     : Mapped "{[/application/metrics/{name:.*}],methods=[GET],produces=[application/vnd.spring-boot.actuator.v2+json || application/json]}" onto public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.MetricsMvcEndpoint.value(java.lang.String)
2018-06-15 15:06:12.632  INFO 14536 --- [           main] o.s.b.a.e.mvc.EndpointHandlerMapping     : Mapped "{[/application/metrics || /application/metrics.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v2+json || application/json]}" onto public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.EndpointMvcAdapter.invoke()
2018-06-15 15:06:12.633  INFO 14536 --- [           main] o.s.b.a.e.mvc.EndpointHandlerMapping     : Mapped "{[/application/auditevents || /application/auditevents.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v2+json || application/json]}" onto public org.springframework.http.ResponseEntity<?> org.springframework.boot.actuate.endpoint.mvc.AuditEventsMvcEndpoint.findByPrincipalAndAfterAndType(java.lang.String,java.util.Date,java.lang.String)
2018-06-15 15:06:12.634  INFO 14536 --- [           main] o.s.b.a.e.mvc.EndpointHandlerMapping     : Mapped "{[/application/env/{name:.*}],methods=[GET],produces=[application/vnd.spring-boot.actuator.v2+json || application/json]}" onto public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.EnvironmentMvcEndpoint.value(java.lang.String)
2018-06-15 15:06:12.634  INFO 14536 --- [           main] o.s.b.a.e.mvc.EndpointHandlerMapping     : Mapped "{[/application/env || /application/env.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v2+json || application/json]}" onto public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.EndpointMvcAdapter.invoke()
2018-06-15 15:06:12.635  INFO 14536 --- [           main] o.s.b.a.e.mvc.EndpointHandlerMapping     : Mapped "{[/application/autoconfig || /application/autoconfig.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v2+json || application/json]}" onto public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.EndpointMvcAdapter.invoke()
2018-06-15 15:06:12.636  INFO 14536 --- [           main] o.s.b.a.e.mvc.EndpointHandlerMapping     : Mapped "{[/application/trace || /application/trace.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v2+json || application/json]}" onto public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.EndpointMvcAdapter.invoke()
2018-06-15 15:06:12.637  INFO 14536 --- [           main] o.s.b.a.e.mvc.EndpointHandlerMapping     : Mapped "{[/application/health || /application/health.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v2+json || application/json]}" onto public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.HealthMvcEndpoint.invoke(javax.servlet.http.HttpServletRequest,java.security.Principal)
2018-06-15 15:06:12.637  INFO 14536 --- [           main] o.s.b.a.e.mvc.EndpointHandlerMapping     : Mapped "{[/application/info || /application/info.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v2+json || application/json]}" onto public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.EndpointMvcAdapter.invoke()
2018-06-15 15:06:12.638  INFO 14536 --- [           main] o.s.b.a.e.mvc.EndpointHandlerMapping     : Mapped "{[/application/mappings || /application/mappings.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v2+json || application/json]}" onto public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.EndpointMvcAdapter.invoke()
2018-06-15 15:06:12.638  INFO 14536 --- [           main] o.s.b.a.e.mvc.EndpointHandlerMapping     : Mapped "{[/application/dump || /application/dump.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v2+json || application/json]}" onto public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.EndpointMvcAdapter.invoke()
2018-06-15 15:06:12.639  INFO 14536 --- [           main] o.s.b.a.e.mvc.EndpointHandlerMapping     : Mapped "{[/application/configprops || /application/configprops.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v2+json || application/json]}" onto public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.EndpointMvcAdapter.invoke()
2018-06-15 15:06:12.639  INFO 14536 --- [           main] o.s.b.a.e.mvc.EndpointHandlerMapping     : Mapped "{[/application/heapdump || /application/heapdump.json],methods=[GET],produces=[application/octet-stream]}" onto public void org.springframework.boot.actuate.endpoint.mvc.HeapdumpMvcEndpoint.invoke(boolean,javax.servlet.http.HttpServletRequest,javax.servlet.http.HttpServletResponse) throws java.io.IOException,javax.servlet.ServletException
2018-06-15 15:06:12.722  INFO 14536 --- [           main] o.s.j.e.a.AnnotationMBeanExporter        : Registering beans for JMX exposure on startup
2018-06-15 15:06:12.731  INFO 14536 --- [           main] o.s.c.support.DefaultLifecycleProcessor  : Starting beans in phase 0
2018-06-15 15:06:12.818  INFO 14536 --- [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat started on port(s): 8082 (http)
2018-06-15 15:06:12.822  INFO 14536 --- [           main] c.c.s.mysSpringBoot.StartApplication     : Started StartApplication in 2.563 seconds (JVM running for 2.82)

3. @ResponseBody注解

访问2.4.2 中的test方法会404，此时需要在方法上加@ResponseBody注解