这个问题害了我弄了几天才弄好，后来开了/articles/FJnmAvY
这篇文章才算把问题解决了。
首先将spring的bean文件头文件改一下
改成
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="/schema/beans"
xmlns:xsi="/2001/XMLSchema-instance" xmlns:context="/schema/context"
xmlns:aop="/schema/aop" xmlns:tx="/schema/tx"
xmlns:mvc="/schema/mvc"
xsi:schemaLocation="/schema/beans
/schema/beans/spring-beans-3.0.xsd
/schema/context
/schema/context/spring-context-3.0.xsd
/schema/aop
/schema/aop/spring-aop-3.0.xsd
/schema/tx
/schema/tx/spring-tx-3.0.xsd
/schema/mvc
/schema/mvc/spring-mvc-3.2.xsd">
也就是把以前spring-mvc-3.0.xsd 升级到 spring-mvc-3.2.xsd，如果已经是spring-mvc-3.2.xsd的就不用改了
然后把<mvc:annotation-driven>修改成如下格式
<mvc:annotation-driven content-negotiation-manager="contentNegotiationManager" />
<bean id="contentNegotiationManager" class="org.springframework.web.accept.ContentNegotiationManagerFactoryBean">
<property name="favorPathExtension" value="false" />
<property name="favorParameter" value="false" />
<property name="ignoreAcceptHeader" value="false" />
<property name="mediaTypes" >
<value>
atom=application/atom+xml
html=text/html
json=application/json
*=*/*
</value>
</property>
</bean>
jackson的包就引用
jackson-core-2.5.2.jar
jackson-annotations-2.5.2.jar
jackson-databind-2.5.2.jar
这三个包就可以了
