java - 为什么表格数据不能加载？ html和jsp都是放在服务器上面的-PHP中文网问答

<!DOCTYPE html>
<html>
<head lang="en">

<meta charset="UTF-8">
<title></title>
<link rel="stylesheet" href="resources/css/ext-all.css" type="text/css"/>
<!--<script  src="ext-all.js"  type="text/javascript"></script>-->
<script src="ext-all-debug.js" type="text/javascript"></script>
<script src="ext-lang-zh_CN.js" type="text/javascript"></script>

<script type="text/javascript">

       Ext.onReady(function(){
           var  columns=[
               {header:'编号',dataIndex:'id'},
               {header:'名称',dataIndex:'name'},
               {header:'描述',dataIndex:'descn'}

           ];
           var store=new Ext.data.Store({
                proxy:{
                    type:'ajax',
                    url:'11.jsp',
                    reader:{
                        type:'json',
                        totalProperty:'totalProperty',
                        root:'root',
                        idProperty:'id'
                    }
                },
               fields:[
                   {name:'id'},
                   {name:'name'},
                   {name:'descn'}
               ]
           });
     /*      var  data=[
               ['1','name1','descn1'],
               ['1','name1','descn1'],
               ['1','name1','descn1'],
               ['1','name1','descn1'],
               ['1','name1','descn1']
           ];
            var store=new  Ext.data.ArrayStore({
                data:data,
                fields:[
                    {name:'id'},
                    {name:'name'},
                    {name:'descn'}
                ]
            });*/

           var  grid=new  Ext.grid.GridPanel({
               renderTo:'grid',
               autoHeight:true,
               store:store,
               columns:columns,
               bbar:new Ext.PagingToolbar({
                   pageSize:10,
                   store:store,
                   displayInfo:true,
                   displayMsg:'显示第{0}条到{1}条，共{2}条',
                   emptyMsg:'没有记录'
               })

           });
           store.load({params:{start:0,limit:10}});
           });

</script>

</head>
<body>
<p id="grid"></p>
</body>
</html>

//jsp

String  start=request.getParameter('start');
String  limit=request.getParameter('limit');
  try{
     int index=Integer.parseInt(start);
     int pageSize=Integer.parseInt(limit);
     String  json="{totalProperty:100,root:[";
        for (int i=index;i<pageSize+index;i++){
            json+="{id:"+i+",name:'name"+i+"',descn:'descn"+i+"'}";
            if(i!=pageSize+index-1){
              json+=",";
            }
       }
       json+="]}";
       response.getWriter().write(json);

     } catch(Exception  ex){
  }