关于spring mvc error no class def found

Question

我收到错误 NOClassDefFound for org/codehaus/jackson/map/objectmapper ，我的 spring xml 文件如下所示

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xsi:schemaLocation="
     http://www.springframework.org/schema/beans
     http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
     http://www.springframework.org/schema/context
     http://www.springframework.org/schema/context/spring-context-3.0.xsd
     http://www.springframework.org/schema/mvc
     http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd
     ">
<mvc:annotation-driven />
<context:component-scan base-package="org.package.servletname" />

<bean
    class="org.springframework.web.servlet.view.ContentNegotiatingViewResolver">
    <property name="mediaTypes">
        <map>
            <entry key="atom" value="application/atom+xml" />
            <entry key="html" value="text/html" />
            <entry key="json" value="application/json" />
        </map>
    </property>
    <property name="viewResolvers">
        <list>
            <bean class="org.springframework.web.servlet.view.BeanNameViewResolver" />
            <bean
                class="org.springframework.web.servlet.view.InternalResourceViewResolver">
                <property name="prefix" value="/WEB-INF/jsp/" />
                <property name="suffix" value=".jsp" />
            </bean>
        </list>
    </property>
    <property name="defaultViews">
        <list>
            <bean
                class="org.springframework.web.servlet.view.json.MappingJacksonJsonView" />
        </list>
    </property>
</bean>

<mvc:resources mapping="/css/**" location="/css/" />
<mvc:resources mapping="/img/**" location="/img/" />
<mvc:resources mapping="/js/**" location="/js/" />

</beans>

我正在尝试用我的 spring 映射 json，所以请指教。

Answer 1

错误清楚地表明您的类路径中没有 Jackson JAR。您是否在类路径中添加了 Jackson JSON JAR 文件？

• jackson-annotations-2.1.1.jar (download)
• jackson-core-2.1.1.jar (download)
• jackson-databind-2.1.1.jar (download)