問題描述

spingmvc 返回json數據時報錯,spingmvc啟動失敗

嚴重: StandardWrapper.Throwableorg.springframework.beans.factory.BeanCreationException: Error creating bean with name ’org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter’: Initialization of bean failed; nested exception is java.lang.NoClassDefFoundError: com/fasterxml/jackson/core/JsonProcessingException at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:553) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482) at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306)at java.lang.Thread.run(Thread.java:745)

spingmvc-servlet.xml配置如下:

<mvc:annotation-driven><mvc:message-converters> <beanclass='org.springframework.http.converter.ResourceHttpMessageConverter'> </bean> <beanclass='org.springframework.http.converter.json.MappingJackson2HttpMessageConverter'><property name='supportedMediaTypes'> <list><value>text/html;charset=UTF-8</value><value>application/json;charset=UTF-8</value> </list></property> </bean></mvc:message-converters> </mvc:annotation-driven>

pom.xml依賴

<dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-databind</artifactId> <version>2.6.5</version></dependency><dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-core</artifactId> <version>2.6.5</version></dependency><dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-annotations</artifactId> <version>2.6.5</version></dependency>

spring版本是4.xcontroller代碼如下

@Controller@RequestMapping('/json')public class UserController {//用戶注冊 @RequestMapping(value = '/register.do') @ResponseBody public Map<String,Object> register() throws IOException { Map<String,Object> map = new HashMap<String, Object>();map.put('xx', 'ok');return map; }}

瀏覽器輸入

http://localhost:8080/MybatisDemo/json/register.do

后臺就提示啟動springmvc失敗,說是找不json對應的類，可是相關的依賴我都添加了啊。。前臺提示Servlet.init() for servlet springmvc threw exception，忙活半天了。。網上的方案都不能解決.

問題解答

有沒有多個版本的jackson-core???

一般加json-all一個就行了。你試著把其他的包去掉。加上這個試下。