Spring MVC 4.0以后版本返回json格式数据问题

SpringMVC4.0以后版本返回json格式数据问题，有什么偏颇的地方希望大家多多斧正。在这个问题上困扰了我两天，这两天翻来覆去睡不着。一直在想这个问题。废话不多说下面进入正题。1.创建创建web项目，加入SpringMVC的jar,我这里演示用spring-framework-4.2.3.RELEASE。jar包如下图所示：2.配置web.xml如下： <？xml version="1.0" encoding="UTF-8"？>
<web-app version="2.5"
  xmlns="http://java.sun.com/xml/ns/javaee"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
  http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">

  <servlet>
   <servlet-name>SpringMVC</servlet-name>
   <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
   <init-param>
   <param-name>contextConfigLocation</param-name>
   <param-value>classpath:applicationContext.xml</param-value>
   </init-param>
  </servlet>

  <servlet-mapping>
   <servlet-name>SpringMVC</servlet-name>
   <url-pattern>/</url-pattern>
  </servlet-mapping>

</web-app>

3.配置applicationContext.xml<？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: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.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.1.xsd
http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.1.xsd">
<context:component-scan base-package="cn.xugang.."></context:component-scan>
<mvc:annotation-driven content-negotiation-manager="contentNegotiationManagerFactoryBean"/>
<mvc:default-servlet-handler/>
<bean class="org.springframework.web.accept.ContentNegotiationManagerFactoryBean" id="contentNegotiationManagerFactoryBean">
   <property name="favorPathExtension" value="false"/>
   <property name="favorParameter" value="false"/>
   <property name="ignoreAcceptHeader" value="false"/>
   <property name="mediaTypes">
   <map>
   <entry key="xml" value="application/xml"/>
   <entry key="json" value="application/json"/>
   <entry key="xls" value="application/vnd.ms-excel"/>
   </map>
   </property>
</bean>
<bean class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter" id="mappingJacksonHttpMessageConverter">
   <property name="supportedMediaTypes">
   <list>
   <value>text/html;charset=UTF-8</value>
   </list>
   </property>
</bean>
<bean id="annotationMethodHandlerAdapter" class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter">
   <property name="messageConverters">
   <list>
   <ref bean="mappingJacksonHttpMessageConverter"/>
   </list>
   </property>
</bean>


<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
   <property name="prefix" value="/WEB-INF/jsp/"></property>
   <property name="suffix" value=".jsp"></property>
</bean>
</beans>4.配置创建controller，使用@Responsebody注解，指定返回内容。package cn.xugang.cotroller;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;

import cn.xugang.entity.User;

@Controller
@RequestMapping（"/user"）
public class UserCotroller {
  @RequestMapping（value="/hello.html",method=RequestMethod.GET ）
  public @ResponseBody User hello（）{
   User user=new User（）;
   user.setAge（19）;
   user.setName（"test"）;
   return user;
  }
  @RequestMapping（value="/test.html"）
  public String test（）{
   System.out.println（"hello world"）;
   return "hello";
  }
}
5.发送异步请求。这个由于本人用了Etx.js，就直接用ext.js发送异步请求了。Ext.onReady（function（）{
  Ext.define（"User",{
   extend:"Ext.data.Model",
   fields:["name","age"],
  }）;
  var store=Ext.create（"Ext.data.Store",{
   model:"User",
   proxy:{
   type:"ajax",
   url:"/SpringMVC4/user/hello.html",
   reader:{
   type:"json",

   }
   }

  }）;

  store.load（{
   callback:function（records,operation,success）{
   if（success）{
   var msg=[];
   store.each（function（user）{
   msg.push（user.get（"name"）+" "+user.get（"age"））;

   }）;
   Ext.MessageBox.alert（"提示",msg.join（"<br>"））;
   }
   }


  }）;
  var msg=[];
  store.each（function（user）{
   msg.push（person.get（"name"）+" "+user.get（"age"））;

  }）;
  Ext.MessageBox.alert（"提示",msg.join（"<br>"））;

}）;6.结果演示7.总结：最后简单说一下，SpringMVC4.0以上版本用上述这种方式成功返回json，如果是4.0以下，由于json的解析方式不同，这里也是一个坑，在网上收了很多资料，看了说得是云里雾里，完全无法使用，最后经过自己认真总结得出本文所述内容，4.0以下可使用如下jar包。并于applicationContext.xml中配置如下代码<？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: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.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.1.xsd
http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.1.xsd">
<context:component-scan base-package="cn.xugang.."></context:component-scan>
<mvc:annotation-driven/>
<mvc:default-servlet-handler/>
<bean class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter" id="mappingJacksonHttpMessageConverter">
   <property name="supportedMediaTypes">
   <list>
   <value>application/json;charset=UTF-8</value>
   </list>
   </property>
</bean>
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
   <property name="prefix" value="/WEB-INF/jsp/"></property>
   <property name="suffix" value=".jsp"></property>
</bean>
</beans>最后，希望帖子对大家有用，由于第一次写，很多地方写的不是很好，请大家多多包涵.如大家对上述有疑惑，可以留言。如转载请注明出处。谢谢大家！Spring MVC+Spring3+Hibernate4开发环境搭建 http://www.linuxidc.com/Linux/2013-07/87119.htmSpring MVC整合Freemarker基于注解方式 http://www.linuxidc.com/Linux/2013-02/79660.htm基于注解的Spring MVC简单介绍 http://www.linuxidc.com/Linux/2012-02/54896.htmSpring MVC 框架搭建及详解 http://www.linuxidc.com/Linux/2012-01/52740.htmSpring MVC使用Cron表达式的定时器 http://www.linuxidc.com/Linux/2014-12/110733.htm简单的Spring MVC经典案例 http://www.linuxidc.com/Linux/2016-04/129718.htm本文永久更新链接地址：http://www.linuxidc.com/Linux/2016-08/134654.htm