bean with name 'mappingJacksonHttpMessageConverter' defined in class解决办法

先把错误信息帖出来：

Context initialization failedorg.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping': Invocation of init method failed; nested exception is org.springframework.beans.factory.CannotLoadBeanClassException: Cannot find class [org.springframework.http.converter.json.MappingJacksonHttpMessageConverter] for bean with name 'mappingJacksonHttpMessageConverter' defined in class path resource [spring-mvc.xml]; nested exception is java.lang.ClassNotFoundException: org.springframework.http.converter.json.MappingJacksonHttpMessageConverterRelated cause: org.springframework.beans.factory.CannotLoadBeanClassException: Cannot find class [org.springframework.http.converter.json.MappingJacksonHttpMessageConverter] for bean with name 'mappingJacksonHttpMessageConverter' defined in class path resource [spring-mvc.xml]; nested exception is java.lang.ClassNotFoundException: org.springframework.http.converter.json.MappingJacksonHttpMessageConverterat org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1628)at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:555)at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:483)at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306)at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302)at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197)at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:761)at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:867)at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:543)at org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:668)at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:634)at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:682)at org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:553)at org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:494)at org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:171)at javax.servlet.GenericServlet.init(GenericServlet.java:158)at org.apache.catalina.core.StandardWrapper.initServlet(StandardWrapper.java:1284)at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1197)at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:1087)at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:5267)at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5557)at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:901)at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:877)at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:652)at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:1263)at org.apache.catalina.startup.HostConfig$DeployDirectory.run(HostConfig.java:1948)at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)at java.util.concurrent.FutureTask.run(FutureTask.java:262)at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)at java.lang.Thread.run(Thread.java:745)Caused by: org.springframework.beans.factory.CannotLoadBeanClassException: Cannot find class [org.springframework.http.converter.json.MappingJacksonHttpMessageConverter] for bean with name 'mappingJacksonHttpMessageConverter' defined in class path resource [spring-mvc.xml]; nested exception is java.lang.ClassNotFoundException: org.springframework.http.converter.json.MappingJacksonHttpMessageConverterat org.springframework.beans.factory.support.AbstractBeanFactory.resolveBeanClass(AbstractBeanFactory.java:1385)at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.determineTargetType(AbstractAutowireCapableBeanFactory.java:641)at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.predictBeanType(AbstractAutowireCapableBeanFactory.java:609)at org.springframework.beans.factory.support.AbstractBeanFactory.isFactoryBean(AbstractBeanFactory.java:1484)at org.springframework.beans.factory.support.DefaultListableBeanFactory.doGetBeanNamesForType(DefaultListableBeanFactory.java:425)at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBeanNamesForType(DefaultListableBeanFactory.java:403)at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBeanNamesForType(DefaultListableBeanFactory.java:389)at org.springframework.context.support.AbstractApplicationContext.getBeanNamesForType(AbstractApplicationContext.java:1174)at org.springframework.web.servlet.handler.AbstractHandlerMethodMapping.initHandlerMethods(AbstractHandlerMethodMapping.java:199)at org.springframework.web.servlet.handler.AbstractHandlerMethodMapping.afterPropertiesSet(AbstractHandlerMethodMapping.java:184)at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping.afterPropertiesSet(RequestMappingHandlerMapping.java:127)at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1687)at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1624)... 32 moreCaused by: java.lang.ClassNotFoundException: org.springframework.http.converter.json.MappingJacksonHttpMessageConverterat org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1722)at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1573)at org.springframework.util.ClassUtils.forName(ClassUtils.java:250)at org.springframework.beans.factory.support.AbstractBeanDefinition.resolveBeanClass(AbstractBeanDefinition.java:401)at org.springframework.beans.factory.support.AbstractBeanFactory.doResolveBeanClass(AbstractBeanFactory.java:1432)at org.springframework.beans.factory.support.AbstractBeanFactory.resolveBeanClass(AbstractBeanFactory.java:1377)... 44 moreRelated cause:org.springframework.beans.factory.CannotLoadBeanClassException: Cannot find class [org.springframework.http.converter.json.MappingJacksonHttpMessageConverter] for bean with name 'mappingJacksonHttpMessageConverter' defined in class path resource [spring-mvc.xml]; nested exception is java.lang.ClassNotFoundException: org.springframework.http.converter.json.MappingJacksonHttpMessageConverterat org.springframework.beans.factory.support.AbstractBeanFactory.resolveBeanClass(AbstractBeanFactory.java:1385)at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.determineTargetType(AbstractAutowireCapableBeanFactory.java:641)at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.predictBeanType(AbstractAutowireCapableBeanFactory.java:609)at org.springframework.beans.factory.support.AbstractBeanFactory.isFactoryBean(AbstractBeanFactory.java:1484)at org.springframework.beans.factory.support.DefaultListableBeanFactory.doGetBeanNamesForType(DefaultListableBeanFactory.java:425)at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBeanNamesForType(DefaultListableBeanFactory.java:395)at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBeansOfType(DefaultListableBeanFactory.java:515)at org.springframework.context.support.AbstractApplicationContext.getBeansOfType(AbstractApplicationContext.java:1194)at org.springframework.beans.factory.BeanFactoryUtils.beansOfTypeIncludingAncestors(BeanFactoryUtils.java:310)at org.springframework.web.servlet.handler.AbstractHandlerMapping.detectMappedInterceptors(AbstractHandlerMapping.java:272)at org.springframework.web.servlet.handler.AbstractHandlerMapping.initApplicationContext(AbstractHandlerMapping.java:247)at org.springframework.context.support.ApplicationObjectSupport.initApplicationContext(ApplicationObjectSupport.java:120)at org.springframework.web.context.support.WebApplicationObjectSupport.initApplicationContext(WebApplicationObjectSupport.java:76)at org.springframework.context.support.ApplicationObjectSupport.setApplicationContext(ApplicationObjectSupport.java:74)at org.springframework.context.support.ApplicationContextAwareProcessor.invokeAwareInterfaces(ApplicationContextAwareProcessor.java:121)at org.springframework.context.support.ApplicationContextAwareProcessor.postProcessBeforeInitialization(ApplicationContextAwareProcessor.java:97)at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyBeanPostProcessorsBeforeInitialization(AbstractAutowireCapableBeanFactory.java:409)at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1620)at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:555)at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:483)at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306)at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302)at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197)at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:761)at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:867)at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:543)at org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:668)at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:634)at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:682)at org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:553)at org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:494)at org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:171)at javax.servlet.GenericServlet.init(GenericServlet.java:158)at org.apache.catalina.core.StandardWrapper.initServlet(StandardWrapper.java:1284)at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1197)at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:1087)at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:5267)at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5557)at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:901)at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:877)at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:652)at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:1263)at org.apache.catalina.startup.HostConfig$DeployDirectory.run(HostConfig.java:1948)at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)at java.util.concurrent.FutureTask.run(FutureTask.java:262)at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)at java.lang.Thread.run(Thread.java:745)Caused by: java.lang.ClassNotFoundException: org.springframework.http.converter.json.MappingJacksonHttpMessageConverterat org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1722)at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1573)at org.springframework.util.ClassUtils.forName(ClassUtils.java:250)at org.springframework.beans.factory.support.AbstractBeanDefinition.resolveBeanClass(AbstractBeanDefinition.java:401)at org.springframework.beans.factory.support.AbstractBeanFactory.doResolveBeanClass(AbstractBeanFactory.java:1432)at org.springframework.beans.factory.support.AbstractBeanFactory.resolveBeanClass(AbstractBeanFactory.java:1377)... 49 more九月 28, 2017 4:03:20 下午 org.apache.catalina.core.ApplicationContext log严重: StandardWrapper.Throwable

出现这个错误也让我找了好久，起初以为jar包版本不对，后来发现缺少jar包，出现这个错误的时候首先要检查jar包，这三个少不了，我用的maven，我就直接贴出来pom文件配置了：

<!--ajax jackson-core jar -->    <dependency>         <groupId>com.fasterxml.jackson.core</groupId>         <artifactId>jackson-core</artifactId>         <version>2.7.3</version>    </dependency><!--ajax jackson-mapping jar -->    <dependency>        <groupId>org.codehaus.jackson</groupId>        <artifactId>jackson-mapper-asl</artifactId>        <version>1.9.13</version>    </dependency><!-- Caused by: java.lang.NoClassDefFoundError: com/fasterxml/jackson/databind/JavaType --><!--ajax jackson-databind jar -->    <dependency>       <groupId>com.fasterxml.jackson.core</groupId>       <artifactId>jackson-databind</artifactId>       <version>2.7.3</version>    </dependency>

这里根据自己的需要去调整版本就行了，再其次就很明显了，报的错是找不到这个方法：

Cannot find class [org.springframework.http.converter.json.MappingJacksonHttpMessageConverter] for bean with name 'mappingJacksonHttpMessageConverter' defined

最后发现springMVC在配置返回值转换的时候有一下两种方案：

配置文件的配置信息跟jackson的版本有关。

版本一： org.springframework.http.converter.json.MappingJacksonHttpMessageConverter

版本二：org.springframework.http.converter.json.MappingJackson2HttpMessageConverter

版本一找不到换成版本二就可以了，这个引入的jar包版本有关，都试试吧。