extjs 读到的json只显示header 可能是什么原因？

<script type="text/javascript">
   
    Ext.onReady(function(){
              var cm = new Ext.grid.ColumnModel([
                    new Ext.grid.RowNumberer(),
                 {header:'id',dataIndex:'id'},
                 {header:'name',dataIndex:'name'},
                 {header:'position',dataIndex:'position'}
                 ]);                           
             
              var store = new Ext.data.Store({
                   proxy:new Ext.data.HttpProxy({url:'/WEB-INF/pages/list.jsp'}),
                   reader:new Ext.data.JsonReader({
                   totalProperty:'totalCount',
                       root:'result'
                       },[
                   {name:'id'},
                   {name:'name'},
                   {name:'position'}
                   ])
              });
              store.load();
              var grid = new Ext.grid.GridPanel({
                  renderTo:"main",
                  cm:cm,
                  store:store,                                            
                  autoHeight:true
              });

    });
</script>
<div id="main"></div>
只能显示 标头
那个'/WEB-INF/pages/list.jsp' 里面是这句 但是为什么 显示不出来
out.print("{totalCount:10,result:[{id:1,name:'aaa',position:'nbbb'},{id:2,name:'aaa',position:'nbbb'}]}");
问题补充：
不对，我把div设置了 也不行啊
问题补充：
因为我用的是appfuse 框架，然后我新建了一个不用这个的试了下  就Ok  一放到appfuse 框架下的  就会有问题，我想是不是装饰器的问题呢？