我在spring restcontroller示例中遇到错误

Question

这些天我正在学习Java Spring。我正在做一个关于Spring和Rest Api的简单示例。我想在浏览器中写“ Hello World”。我使用了@restController。我可以为我的示例找到任何解决方案。

我的Java代码

package webgroup.webartifact;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class HelloWorldController {

    @RequestMapping(value="/getHelloWorld")
    @ResponseBody
    public String getHelloWorld() {
        return "Hello World ";
    }

}

我的xml文件是

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:mvc="http://www.springframework.org/schema/mvc"
    xmlns:context="http://www.springframework.org/schema/context"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="
        http://www.springframework.org/schema/beans     
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/mvc 
        http://www.springframework.org/schema/mvc/spring-mvc.xsd
        http://www.springframework.org/schema/context 
        http://www.springframework.org/schema/context/spring-context.xsd">

    <context:component-scan base-package="webgroup.webartifact"/>
    <context:annotation-config />

    <bean class= "org.springframework.web.servlet.view.InternalResourceViewResolver" >
        <property name= "prefix">
            <value>/WEB-INF/</value>
        </property>

        <property name= "suffix">
        <value>.jsp</value>
        </property>
    </bean>
  </beans>  

还有我的pom.xml文件。

<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>webgroup</groupId>
  <artifactId>webartifact</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <packaging>jar</packaging>

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

  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <jdk.version>1.6</jdk.version>
    <spring.version>3.2.13.RELEASE</spring.version>
    <jstl.version>1.2</jstl.version>
  </properties>

  <dependencies>

    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-webmvc</artifactId>
        <version>${spring.version}</version>
    </dependency>

    <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>jstl</artifactId>
        <version>${jstl.version}</version>
    </dependency>

    <dependency>
    <groupId>javax.servlet</groupId>
    <artifactId>javax.servlet-api</artifactId>
    <version>3.1.0</version>
    <scope>provided</scope>
    </dependency>

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

   <dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-web</artifactId>
    <version>5.1.1.RELEASE</version>
   </dependency>

  </dependencies>

</project>

当我运行此项目时，将显示http状态500错误。我搜索错误，但没有解决方法。

这是错误代码。

HTTP Status 500 – Internal Server Error
Type Exception Report

Message Servlet.init() for servlet [spring-mvc] threw exception

Description The server encountered an unexpected condition that prevented it from fulfilling the request.

Exception

javax.servlet.ServletException: Servlet.init() for servlet [spring-mvc] threw exception
    org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:490)
    org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)
    org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:668)
    org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)
    org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:408)
    org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
    org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:770)
    org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1415)
    org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
    java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    java.lang.Thread.run(Unknown Source)
Root Cause

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter': Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter]: Constructor threw exception; nested exception is java.lang.NoClassDefFoundError: org/springframework/http/MediaType
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateBean(AbstractAutowireCapableBeanFactory.java:1039)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:985)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:487)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:458)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:289)
    org.springframework.web.servlet.DispatcherServlet.createDefaultStrategy(DispatcherServlet.java:807)
    org.springframework.web.servlet.DispatcherServlet.getDefaultStrategies(DispatcherServlet.java:776)
    org.springframework.web.servlet.DispatcherServlet.initHandlerAdapters(DispatcherServlet.java:584)
    org.springframework.web.servlet.DispatcherServlet.initStrategies(DispatcherServlet.java:441)
    org.springframework.web.servlet.DispatcherServlet.onRefresh(DispatcherServlet.java:429)
    org.springframework.web.servlet.FrameworkServlet.onApplicationEvent(FrameworkServlet.java:789)
    org.springframework.web.servlet.FrameworkServlet$ContextRefreshListener.onApplicationEvent(FrameworkServlet.java:1100)
    org.springframework.web.servlet.FrameworkServlet$ContextRefreshListener.onApplicationEvent(FrameworkServlet.java:1097)
    org.springframework.context.event.GenericApplicationListenerAdapter.onApplicationEvent(GenericApplicationListenerAdapter.java:51)
    org.springframework.context.event.SourceFilteringListener.onApplicationEventInternal(SourceFilteringListener.java:96)
    org.springframework.context.event.SourceFilteringListener.onApplicationEvent(SourceFilteringListener.java:68)
    org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:96)
    org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:334)
    org.springframework.context.support.AbstractApplicationContext.finishRefresh(AbstractApplicationContext.java:950)
    org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:482)
    org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:651)
    org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:602)
    org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:665)
    org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:521)
    org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:462)
    org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:136)
    javax.servlet.GenericServlet.init(GenericServlet.java:158)
    org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:490)
    org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)
    org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:668)
    org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)
    org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:408)
    org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
    org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:770)
    org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1415)
    org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
    java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    java.lang.Thread.run(Unknown Source)
Root Cause

org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter]: Constructor threw exception; nested exception is java.lang.NoClassDefFoundError: org/springframework/http/MediaType
    org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:163)
    org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:87)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateBean(AbstractAutowireCapableBeanFactory.java:1032)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:985)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:487)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:458)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:289)
    org.springframework.web.servlet.DispatcherServlet.createDefaultStrategy(DispatcherServlet.java:807)
    org.springframework.web.servlet.DispatcherServlet.getDefaultStrategies(DispatcherServlet.java:776)
    org.springframework.web.servlet.DispatcherServlet.initHandlerAdapters(DispatcherServlet.java:584)
    org.springframework.web.servlet.DispatcherServlet.initStrategies(DispatcherServlet.java:441)
    org.springframework.web.servlet.DispatcherServlet.onRefresh(DispatcherServlet.java:429)
    org.springframework.web.servlet.FrameworkServlet.onApplicationEvent(FrameworkServlet.java:789)
    org.springframework.web.servlet.FrameworkServlet$ContextRefreshListener.onApplicationEvent(FrameworkServlet.java:1100)
    org.springframework.web.servlet.FrameworkServlet$ContextRefreshListener.onApplicationEvent(FrameworkServlet.java:1097)
    org.springframework.context.event.GenericApplicationListenerAdapter.onApplicationEvent(GenericApplicationListenerAdapter.java:51)
    org.springframework.context.event.SourceFilteringListener.onApplicationEventInternal(SourceFilteringListener.java:96)
    org.springframework.context.event.SourceFilteringListener.onApplicationEvent(SourceFilteringListener.java:68)
    org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:96)
    org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:334)
    org.springframework.context.support.AbstractApplicationContext.finishRefresh(AbstractApplicationContext.java:950)
    org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:482)
    org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:651)
    org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:602)
    org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:665)
    org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:521)
    org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:462)
    org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:136)
    javax.servlet.GenericServlet.init(GenericServlet.java:158)
    org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:490)
    org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)
    org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:668)
    org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)
    org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:408)
    org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
    org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:770)
    org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1415)
    org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
    java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    java.lang.Thread.run(Unknown Source)
Root Cause

java.lang.NoClassDefFoundError: org/springframework/http/MediaType
    org.springframework.http.converter.StringHttpMessageConverter.<init>(StringHttpMessageConverter.java:65)
    org.springframework.http.converter.StringHttpMessageConverter.<init>(StringHttpMessageConverter.java:57)
    org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.<init>(AnnotationMethodHandlerAdapter.java:201)
    sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
    sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
    java.lang.reflect.Constructor.newInstance(Unknown Source)
    org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:148)
    org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:87)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateBean(AbstractAutowireCapableBeanFactory.java:1032)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:985)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:487)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:458)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:289)
    org.springframework.web.servlet.DispatcherServlet.createDefaultStrategy(DispatcherServlet.java:807)
    org.springframework.web.servlet.DispatcherServlet.getDefaultStrategies(DispatcherServlet.java:776)
    org.springframework.web.servlet.DispatcherServlet.initHandlerAdapters(DispatcherServlet.java:584)
    org.springframework.web.servlet.DispatcherServlet.initStrategies(DispatcherServlet.java:441)
    org.springframework.web.servlet.DispatcherServlet.onRefresh(DispatcherServlet.java:429)
    org.springframework.web.servlet.FrameworkServlet.onApplicationEvent(FrameworkServlet.java:789)
    org.springframework.web.servlet.FrameworkServlet$ContextRefreshListener.onApplicationEvent(FrameworkServlet.java:1100)
    org.springframework.web.servlet.FrameworkServlet$ContextRefreshListener.onApplicationEvent(FrameworkServlet.java:1097)
    org.springframework.context.event.GenericApplicationListenerAdapter.onApplicationEvent(GenericApplicationListenerAdapter.java:51)
    org.springframework.context.event.SourceFilteringListener.onApplicationEventInternal(SourceFilteringListener.java:96)
    org.springframework.context.event.SourceFilteringListener.onApplicationEvent(SourceFilteringListener.java:68)
    org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:96)
    org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:334)
    org.springframework.context.support.AbstractApplicationContext.finishRefresh(AbstractApplicationContext.java:950)
    org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:482)
    org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:651)
    org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:602)
    org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:665)
    org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:521)
    org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:462)
    org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:136)
    javax.servlet.GenericServlet.init(GenericServlet.java:158)
    org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:490)
    org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)
    org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:668)
    org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)
    org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:408)
    org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
    org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:770)
    org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1415)
    org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
    java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    java.lang.Thread.run(Unknown Source)
Note The full stack trace of the root cause is available in the server logs.

Answer 1

是否可以从pom中删除spring-web依赖项并将spring版本升级到4.3.2，并且还请从控制器方法中删除@ResponseBody批注，因为它在那里没有用

Answer 2

它抱怨找不到类 org.springframework.http.MediaType 。

此类包装在 spring-web API中，该API与 spring-webmvc 捆绑在一起在pom.xml文件中作为依赖项添加的代码。因此，您应该不会遇到错误。

删除 spring-web 依赖性，因为它是随 spring-webmvc < / em>，这将覆盖与 spring-webmvc 添加的 spring-web 。确保pom.xml文件中没有错误，然后运行 mvn install 或 mvn软件包下载所有依赖项。