用jsonp解决ajax跨域请求

1、页面代码：

$.ajax({   type : "POST",   url : '请求路径?jsoncallback=?&参数',   dataType:'jsonp',   async : false,   success : function(data) {       },   error : function(data) {         }});

2、后台代码:

@ResponseBody@RequestMapping(value = "/getMapEngineInfo")public String getMapEngineInfo(HttpSession session,HttpServletRequest request, ModelMap map,                                 HttpServletResponse res,      @RequestParam(value = "mapType", required = false) String modularCode) throws Exception {      Map<String, Object> result = new HashMap<String, Object>();      String jsoncallback = request.getParameter("jsoncallback");   try {      jsoncallback = jsoncallback + "(" + JsonHelper.getJsonString(result) + ")";   } catch (Exception e) {      e.printStackTrace();   }   return jsoncallback;}