方法一，使用（produces = "application/json; charset=utf-8"）：
@RequestMapping(value="/getUsersByPage",produces = "application/json; charset=utf-8")
// @RequestMapping("/getUsersByPage")
@ResponseBody
public String getUsersByPage(String page,String rows,String text,HttpServletRequest request,HttpServletResponse response){
方法二，在spring-mvc.xml中添加：
<!-- 处理请求返回json字符串的中文乱码问题 -->
<mvc:annotation-driven>
<mvc:message-converters>
<bean class="org.springframework.http.converter.StringHttpMessageConverter">
<property name="supportedMediaTypes">
<list>
<value>application/json;charset=UTF-8</value>
</list>
</property>
</bean>
</mvc:message-converters>
</mvc:annotation-driven>
springmvc @responsebody json字符编码
原文：http://www.cnblogs.com/go4mi/p/5841538.html