PageHelper 中文乱码
在springmvc 的 mvc:annotation-driven 中配置编码
<mvc:annotation-driven /> 会自动注册DefaultAnnotationHandlerMapping与AnnotationMethodHandlerAdapter 两个bean,是spring MVC为@Controllers分发请求所必须的，即解决了@Controller注解使用的前提配置。
<mvc:annotation-driven /> is actually rather pointless. It declares explicit support for annotation-driven MVC controllers (i.e.@RequestMapping, @Controller, etc), even though support for those is the default behaviour.
response.setCharacterEncoding("text/html;charset=UTF-8")； 加在json对象前
