java - Spring Boot相关问题

Question

以下代码出现 Spring 启动问题。看到下面的错误，tomcat 运行正常

package com.template;

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

@SpringBootApplication
public class SpringBootFreemarkerApplication {

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

package controller;

import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;

@Controller
public class TestController {
    @RequestMapping("/welcome")
    public String hello(Model model, @RequestParam(value="name",  
    required=false, defaultValue="World") String name) {
        model.addAttribute("name", name);
        return "welcome";
    }
}



"C:\Program Files\Java\jdk1.8.0_121\bin\java" "-javaagent:C:\Program Files\JetBrains\IntelliJ IDEA Community Edition 2017.1.5\lib\idea_rt.jar=54267:C:\Program Files\JetBrains\IntelliJ IDEA Community Edition 2017.1.5\bin" -Dfile.encoding=UTF-8 -classpath "C:\Program Files\Java\jdk1.8.0_121\jre\lib\charsets.jar;C:\Program Files\Java\jdk1.8.0_121\jre\lib\deploy.jar;C:\Program Files\Java\jdk1.8.0_121\jre\lib\ext\access-bridge-64.jar;C:\Program Files\Java\jdk1.8.0_121\jre\lib\ext\cldrdata.jar;C:\Program Files\Java\jdk1.8.0_121\jre\lib\ext\dnsns.jar;C:\Program Files\Java\jdk1.8.0_121\jre\lib\ext\jaccess.jar;C:\Program Files\Java\jdk1.8.0_121\jre\lib\ext\jfxrt.jar;C:\Program Files\Java\jdk1.8.0_121\jre\lib\ext\localedata.jar;C:\Program Files\Java\jdk1.8.0_121\jre\lib\ext\nashorn.jar;C:\Program Files\Java\jdk1.8.0_121\jre\lib\ext\sunec.jar;C:\Program Files\Java\jdk1.8.0_121\jre\lib\ext\sunjce_provider.jar;C:\Program Files\Java\jdk1.8.0_121\jre\lib\ext\sunmscapi.jar;C:\Program Files\Java\jdk1.8.0_121\jre\lib\ext\sunpkcs11.jar;C:\Program Files\Java\jdk1.8.0_121\jre\lib\ext\zipfs.jar;C:\Program Files\Java\jdk1.8.0_121\jre\lib\javaws.jar;C:\Program Files\Java\jdk1.8.0_121\jre\lib\jce.jar;C:\Program Files\Java\jdk1.8.0_121\jre\lib\jfr.jar;C:\Program Files\Java\jdk1.8.0_121\jre\lib\jfxswt.jar;C:\Program Files\Java\jdk1.8.0_121\jre\lib\jsse.jar;C:\Program Files\Java\jdk1.8.0_121\jre\lib\management-agent.jar;C:\Program Files\Java\jdk1.8.0_121\jre\lib\plugin.jar;C:\Program Files\Java\jdk1.8.0_121\jre\lib\resources.jar;C:\Program Files\Java\jdk1.8.0_121\jre\lib\rt.jar;C:\SpringBoot\Spring-boot-freemarker\target\classes;C:\Users\shekhar\.m2\repository\org\springframework\boot\spring-boot-starter-freemarker\1.5.6.RELEASE\spring-boot-starter-freemarker-1.5.6.RELEASE.jar;C:\Users\shekhar\.m2\repository\org\springframework\boot\spring-boot-starter\1.5.6.RELEASE\spring-boot-starter-1.5.6.RELEASE.jar;C:\Users\shekhar\.m2\repository\org\springframework\boot\spring-boot\1.5.6.RELEASE\spring-boot-1.5.6.RELEASE.jar;C:\Users\shekhar\.m2\repository\org\springframework\boot\spring-boot-autoconfigure\1.5.6.RELEASE\spring-boot-autoconfigure-1.5.6.RELEASE.jar;C:\Users\shekhar\.m2\repository\org\springframework\boot\spring-boot-starter-logging\1.5.6.RELEASE\spring-boot-starter-logging-1.5.6.RELEASE.jar;C:\Users\shekhar\.m2\repository\ch\qos\logback\logback-classic\1.1.11\logback-classic-1.1.11.jar;C:\Users\shekhar\.m2\repository\ch\qos\logback\logback-core\1.1.11\logback-core-1.1.11.jar;C:\Users\shekhar\.m2\repository\org\slf4j\jcl-over-slf4j\1.7.25\jcl-over-slf4j-1.7.25.jar;C:\Users\shekhar\.m2\repository\org\slf4j\jul-to-slf4j\1.7.25\jul-to-slf4j-1.7.25.jar;C:\Users\shekhar\.m2\repository\org\slf4j\log4j-over-slf4j\1.7.25\log4j-over-slf4j-1.7.25.jar;C:\Users\shekhar\.m2\repository\org\yaml\snakeyaml\1.17\snakeyaml-1.17.jar;C:\Users\shekhar\.m2\repository\org\freemarker\freemarker\2.3.26-incubating\freemarker-2.3.26-incubating.jar;C:\Users\shekhar\.m2\repository\org\springframework\spring-context-support\4.3.10.RELEASE\spring-context-support-4.3.10.RELEASE.jar;C:\Users\shekhar\.m2\repository\org\springframework\spring-beans\4.3.10.RELEASE\spring-beans-4.3.10.RELEASE.jar;C:\Users\shekhar\.m2\repository\org\springframework\spring-context\4.3.10.RELEASE\spring-context-4.3.10.RELEASE.jar;C:\Users\shekhar\.m2\repository\org\springframework\boot\spring-boot-starter-web\1.5.6.RELEASE\spring-boot-starter-web-1.5.6.RELEASE.jar;C:\Users\shekhar\.m2\repository\org\springframework\boot\spring-boot-starter-tomcat\1.5.6.RELEASE\spring-boot-starter-tomcat-1.5.6.RELEASE.jar;C:\Users\shekhar\.m2\repository\org\apache\tomcat\embed\tomcat-embed-core\8.5.16\tomcat-embed-core-8.5.16.jar;C:\Users\shekhar\.m2\repository\org\apache\tomcat\embed\tomcat-embed-el\8.5.16\tomcat-embed-el-8.5.16.jar;C:\Users\shekhar\.m2\repository\org\apache\tomcat\embed\tomcat-embed-websocket\8.5.16\tomcat-embed-websocket-8.5.16.jar;C:\Users\shekhar\.m2\repository\org\hibernate\hibernate-validator\5.3.5.Final\hibernate-validator-5.3.5.Final.jar;C:\Users\shekhar\.m2\repository\javax\validation\validation-api\1.1.0.Final\validation-api-1.1.0.Final.jar;C:\Users\shekhar\.m2\repository\org\jboss\logging\jboss-logging\3.3.1.Final\jboss-logging-3.3.1.Final.jar;C:\Users\shekhar\.m2\repository\com\fasterxml\classmate\1.3.3\classmate-1.3.3.jar;C:\Users\shekhar\.m2\repository\com\fasterxml\jackson\core\jackson-databind\2.8.9\jackson-databind-2.8.9.jar;C:\Users\shekhar\.m2\repository\com\fasterxml\jackson\core\jackson-annotations\2.8.0\jackson-annotations-2.8.0.jar;C:\Users\shekhar\.m2\repository\com\fasterxml\jackson\core\jackson-core\2.8.9\jackson-core-2.8.9.jar;C:\Users\shekhar\.m2\repository\org\springframework\spring-web\4.3.10.RELEASE\spring-web-4.3.10.RELEASE.jar;C:\Users\shekhar\.m2\repository\org\springframework\spring-aop\4.3.10.RELEASE\spring-aop-4.3.10.RELEASE.jar;C:\Users\shekhar\.m2\repository\org\springframework\spring-webmvc\4.3.10.RELEASE\spring-webmvc-4.3.10.RELEASE.jar;C:\Users\shekhar\.m2\repository\org\springframework\spring-expression\4.3.10.RELEASE\spring-expression-4.3.10.RELEASE.jar;C:\Users\shekhar\.m2\repository\org\slf4j\slf4j-api\1.7.25\slf4j-api-1.7.25.jar;C:\Users\shekhar\.m2\repository\org\springframework\spring-core\4.3.10.RELEASE\spring-core-4.3.10.RELEASE.jar" com.template.SpringBootFreemarkerApplication

  .   ____          _            __ _ _
 /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
 \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::        (v1.5.6.RELEASE)

2017-07-30 15:20:08.005  INFO 7612 --- [           main] c.t.SpringBootFreemarkerApplication      : Starting SpringBootFreemarkerApplication on DESKTOP-9LIAED5 with PID 7612 (C:\SpringBoot\Spring-boot-freemarker\target\classes started by shekhar in C:\SpringBoot\Spring-boot-freemarker)
2017-07-30 15:20:08.008  INFO 7612 --- [           main] c.t.SpringBootFreemarkerApplication      : No active profile set, falling back to default profiles: default
2017-07-30 15:20:08.074  INFO 7612 --- [           main] ationConfigEmbeddedWebApplicationContext : Refreshing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@3bd94634: startup date [Sun Jul 30 15:20:08 IST 2017]; root of context hierarchy
2017-07-30 15:20:10.322  INFO 7612 --- [           main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat initialized with port(s): 8080 (http)
2017-07-30 15:20:10.333  INFO 7612 --- [           main] o.apache.catalina.core.StandardService   : Starting service [Tomcat]
2017-07-30 15:20:10.334  INFO 7612 --- [           main] org.apache.catalina.core.StandardEngine  : Starting Servlet Engine: Apache Tomcat/8.5.16
2017-07-30 15:20:10.472  INFO 7612 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext
2017-07-30 15:20:10.472  INFO 7612 --- [ost-startStop-1] o.s.web.context.ContextLoader            : Root WebApplicationContext: initialization completed in 2398 ms
2017-07-30 15:20:10.788  INFO 7612 --- [ost-startStop-1] o.s.b.w.servlet.ServletRegistrationBean  : Mapping servlet: 'dispatcherServlet' to [/]
2017-07-30 15:20:10.792  INFO 7612 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'characterEncodingFilter' to: [/*]
2017-07-30 15:20:10.792  INFO 7612 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'hiddenHttpMethodFilter' to: [/*]
2017-07-30 15:20:10.793  INFO 7612 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'httpPutFormContentFilter' to: [/*]
2017-07-30 15:20:10.793  INFO 7612 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean   : Mapping filter: 'requestContextFilter' to: [/*]
2017-07-30 15:20:11.221  INFO 7612 --- [           main] s.w.s.m.m.a.RequestMappingHandlerAdapter : Looking for @ControllerAdvice: org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@3bd94634: startup date [Sun Jul 30 15:20:08 IST 2017]; root of context hierarchy
2017-07-30 15:20:11.299  INFO 7612 --- [           main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped "{[/welcome]}" onto public java.lang.String com.template.controller.TestController.hello(org.springframework.ui.Model,java.lang.String)
2017-07-30 15:20:11.302  INFO 7612 --- [           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)
2017-07-30 15:20:11.302  INFO 7612 --- [           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)
2017-07-30 15:20:11.337  INFO 7612 --- [           main] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/webjars/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2017-07-30 15:20:11.337  INFO 7612 --- [           main] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2017-07-30 15:20:11.374  INFO 7612 --- [           main] o.s.w.s.handler.SimpleUrlHandlerMapping  : Mapped URL path [/**/favicon.ico] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2017-07-30 15:20:11.626  INFO 7612 --- [           main] o.s.w.s.v.f.FreeMarkerConfigurer         : ClassTemplateLoader for Spring macros added to FreeMarker configuration
2017-07-30 15:20:11.727  INFO 7612 --- [           main] o.s.j.e.a.AnnotationMBeanExporter        : Registering beans for JMX exposure on startup
2017-07-30 15:20:11.790  INFO 7612 --- [           main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat started on port(s): 8080 (http)
2017-07-30 15:20:11.795  INFO 7612 --- [           main] c.t.SpringBootFreemarkerApplication      : Started SpringBootFreemarkerApplication in 4.222 seconds (JVM running for 5.046)

Answer 1

Spring Boot 提供的默认组件扫描不会扫描您的 Controller 。默认情况下，Spring boot 从包含“主”类的包(用 @SpringBootApplication 注释的包)启动，并且还会扫描它的所有子包。

您的主类位于package com.template;中，但 Controller 位于packagecontroller;中。将 Controller 移动到名为 package com.template.controller;

的包中