在JavaWEB项目中,使用SSM框架,在项目启动时出现如下错误:
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.MappingJacksonHttpMessageConverter
查看之后,出错的地方为配置文件中配置了一个bean,id为mappingJacksonHttpMessageConverter,class为
“org.springframework.http.converter.json.MappingJacksonHttpMessageConverter”,
1 <!--避免IE执行AJAX时,返回JSON出现下载文件 --> 2 <bean id="mappingJacksonHttpMessageConverter" 3 class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter"> 4 <property name="supportedMediaTypes"> 5 <list> 6 <value>text/html;charset=UTF-8</value> 7 </list> 8 </property> 9 </bean> 10 <mvc:annotation-driven> 11 <mvc:message-converters register-defaults="true"> 12 <bean 13 class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter" 14 p:supportedMediaTypes="*/*" /> 15 </mvc:message-converters> 16 </mvc:annotation-driven> 17
启动时读取配置文件,初始化bean时,找不到这个类,改错好几次,纠结很久之后,发现其实就是和所用的的Spring框架的版本有关,这个要注意spring版本,3.x和4.x配置不同
spring3.x是org.springframework.http.converter.json.MappingJacksonHttpMessageConverter
spring4.x是org.springframework.http.converter.json.MappingJackson2HttpMessageConverter
最后修改为:
1 <bean id="mappingJacksonHttpMessageConverter" 2 class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter"> 3 <property name="supportedMediaTypes"> 4 <list> 5 <value>text/html;charset=UTF-8</value> 6 </list> 7 </property> 8 </bean> 9 <mvc:annotation-driven> 10 <mvc:message-converters register-defaults="true"> 11 <bean 12 class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter" 13 p:supportedMediaTypes="*/*" /> 14 </mvc:message-converters> 15 </mvc:annotation-driven> 16
其实只要改一下类名就可以,具体可以查看spring-web的jar确认,哪个存在用哪个!