我们都知道使用Springmvc的ajax很强大只要三步就可以实现：

1.引入jackson的maven到pom文件：

com.fasterxml.jackson.core jackson-databind 2.9.5

com.fasterxml.jackson.core jackson-core 2.9.5
com.fasterxml.jackson.core jackson-annotations 2.9.5

2.配置

3.RequestMapping和ResponseBody的连用

但是项目启动的时候报错：

org.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 java.lang.NoSuchMethodError: org.springframework.aop.support.AopUtils.selectInvocableMethod(Ljava/lang/reflect/Method;Ljava/lang/Class;)Ljava/lang/reflect/Method;
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1578)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:545)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:305)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:301)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:196)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:772)
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:834)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:537)
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)

大家不用慌张：

有的时候就是这样，我们就是用不了 

划重点=====================================================================================================================

此时此刻：在SpringMVC的配置中把去掉加上这几行代码

<!--json转化器，它可以将结果转化-->  
<bean id="mappingJacksonHttpMessageConverter"  
      class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter">  
    <property name="supportedMediaTypes">  
        <list>  
            <value>text/html;charset=UTF-8</value>  
        </list>  
    </property>  
</bean>  
<!-- 启动SpringMVC的注解功能，完成请求和注解POJO的映射 -->  
<bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter">  
    <property name="messageConverters">  
        <list>  
            <ref bean="mappingJacksonHttpMessageConverter" /> <!-- JSON转换器 -->  
        </list>  
    </property>  
</bean>

这时候再次启动项目就ok娄！！！