Jquery跨域调用struts2的Action返回json数据易出现的问题

必须有jsoncallback

1.

$.getJSON("/queryName.action?jsoncallback=?",function(json){

                 alert(" json ="+ json );

                 console.log( json );

            });

2.

            < action name = "queryName" method = "queryName" class = "testAction" >

                 < result name = "success" type = "json" >

                      < param name="callbackParameter">jsoncallbackparam>

                 result >  

            action >

3.

try {

                 userList = userService .queryInfoByUserId( userId );

                 if (!CollectionUtils.isEmpty( userPostList )){

                     code = userList .get(0).getCode();

                     name = userList .get(0).getName();

                }

              

                Map map = new HashMap();

                map.put( "name" , name);

                map.put( "id" , code);

                JSONArray arr=JSONArray .fromObject(map);

                String  callback = jsoncallback;

             String jsoncallback = callback+ "({'result':" +arr+ "})" ;

             JsonFormatUtil.returnJsonResponse(jsoncallback);

           } catch (Exception e) {

                JsonFormatUtil.returnErrorMsgInfoResponse(e.getMessage());

                e.printStackTrace();

           }

           

            return null ;