对于json，Access-Control-Allow-Origin不允许使用原点null

Question

我正在使用这个ajax来调用json文件，但不知怎的，我不断收到此错误消息：“Access-Control-Allow-Origin不允许使用Origin null。”

这是我从学校内部网URL调用的代码。

$.ajax({
type:"get",
url:"http://172.20.192.218:8080/DC_Local/rest/datacorrelation?type=/soccer/football_team&limit=20",
dataType: json,
success: function(data){
var pts = [];
$.each(json.data, function(i,v){
    pts.push([v.topic, v.audience.length]);
});
},

error: function (){
alert("Error"); 
}
});

这是我的json结构：

"data": [
                     {
                         "id": "/en/chelsea_fc",
                         "topic": "Chelsea F.C.",
                         "audience": [
                             {
                                 "userid": "100003914111287",
                                 "information": [
                                     {
                                         "category": "Athlete",
                                         "source": "Didier Drogba"
                                     },
                                     {
                                         "category": "Athlete",
                                         "source": "Frank Lampard"
                                     },
                                     {
                                         "category": "Professional sports team",
                                         "source": "Chelsea Football Club"
                                     },
                                     {
                                         "category": "favorite_teams",
                                         "source": "Chelsea Football Club"
                                     }
                                 ]
                             },
                             {
                                 "userid": "100003914111287",
                                 "information": [
                                     {
                                         "category": "Athlete",
                                         "source": "Didier Drogba"
                                     },
                                     {
                                         "category": "Athlete",
                                         "source": "Frank Lampard"
                                     },
                                     {
                                         "category": "Professional sports team",
                                         "source": "Chelsea Football Club"
                                     },
                                     {
                                         "category": "favorite_teams",
                                         "source": "Chelsea Football Club"
                                     }
                                 ]
                             }
                         ],
                         "type": "/soccer/football_team"
                     },
                     {
                         "id": "/en/manchester_united_fc",
                         "topic": "Manchester United F.C.",
                         "audience": [
                             {
                                 "information": [
                                     {
                                         "category": "Athlete",
                                         "source": "Ryan Giggs"
                                     },
                                     {
                                         "category": "Professional sports team",
                                         "source": "Manchester United"
                                     },
                                     {
                                         "category": "favorite_teams",
                                         "source": "Manchester United"
                                     }
                                 ],
                                 "userid": "100003921730958"
                             }
                         ],
                         "type": "/soccer/football_team"
                     }
                 ]
             }