struts jqery ajax 无刷新 分页

一个简单的分页 jqery ajax 才开始学 ，写的不是很好

action 

public String queryAllajax(){
	   ActionContext context = ActionContext.getContext();
	   HttpServletRequest request = ServletActionContext.getRequest();
	   int page = Integer.valueOf(request.getParameter("page"));
	   int pageSize = 5;//偏移量，每次要查询出的pageSize条记录
       int pageNow = Integer.valueOf(request.getParameter("page"));
       //当前页码
       int pageCount = 0;//总页数
       int onset = 0;//起始记录位置
       int offset = 0; //结尾记录位置
       List<AssistantInfo> list = new ArrayList<AssistantInfo>();
       try {
           int count = InfoFactory.getInstance().getItemNum();//总记录数
           pageCount = (count + pageSize - 1) / pageSize;//计算出总页数
           if (pageNow < 1) {
               pageNow = 1;
           }
           if (pageNow > pageCount) {
               pageNow = pageCount;
           }

           onset = (pageNow - 1) * pageSize;
           offset = onset + pageSize;
           
           list = InfoFactory.getInstance().queryAll(offset, onset);//查询出所有的信息
           	StringBuffer dataSource = new StringBuffer();
           	dataSource.append("{\"dataSource\":");
           	dataSource.append(JsonUtils.listToJson(list));//把list转换为json
           	
            Map map = new HashMap();
            map.put("pageCount", pageCount);
            map.put("pageNow", pageNow);
            map.put("count",count);
            map.put("pageSize",pageSize );
           String s= JsonUtils.mapToJson(map);//把map转换为json
           dataSource.append(",\"pageSource\":[");
           dataSource.append(s);// 总页数、当前页码 添加到json 
           dataSource.append("]}"); 
          
           System.out.println(dataSource);
           HttpServletResponse response = ServletActionContext.getResponse(); 
           response.setContentType("text/javascript");//数据按照js格式送回去
           response.setCharacterEncoding("UTF-8");
           PrintWriter out = response.getWriter();
          out.write(dataSource.toString());
          out.flush();
          out.close();
   }
   catch (Exception e) {
       e.printStackTrace();
   }
	   
	   return  null;
   }

js代码

//进入页面时查询的数据
$(document).ready(function(){
   var page=1;
   jqeryajax(page);
	
});

//首页
 function firstpage(){
	var page= document.listpage.pagenumber.value = 1;
	 jqeryajax(page);
 }
//上一页
	function prepage(){
  		var page = document.listpage.pagenumber.value;
  		page = parseInt(page);
		if(page>1){
			page -= 1;
			document.listpage.pagenumber.value = page;
		}
		 jqeryajax(page);
	} 

//下一页

  function nextpage(){
	   
	  $(document).ready(function(){
	  
	  var page = document.listpage.pagenumber.value;
	  page = parseInt(page);
	  page += 1;
		 document.listpage.pagenumber.value = page;
		 jqeryajax(page);
		 
	  });
	 }
//尾页
  function lastpage(){
		var page=document.getElementById('myspan').innerHTML;/取出span里值
		 jqeryajax(page);
	}
	
  // 查询数据的分页跳转  
	 function jqeryajax(page){
		  
		  $.ajax({
			  url:'ass/assinfo_queryAllajax.action?page='+page,
	    	  type:"POST",
			   dataType:'json',
			  success:function(data){
			   $(data).each(function() {
				   insertTr(data); 
			});
			   
			  }
		  });
 } 

  function insertTr(data) {
	  
      //读取tr里数量  
     var r = $("#datasource tr").size(); 
    // alert("r"+r);
		  	var num = 0;
			if(r < 1){
				num = 1;
			}else if(r > 1){ 
		 $("#datasource").find("tr:not(:first)").remove();  
			}
      var list = data.dataSource;//查询出的数据
      var list1 = data.pageSource;//总页数、当前页码
      

     $.each(list1,function(i, item){
      //   alert("pageSize"+item.pageSize+"pageNow"+item.pageNow);
         $("#myspan").html(item.pageCount);
           $("#pagenumber").val(item.pageNow);

         });
      
      $.each(list, function(i, r) {  
          //克隆已有的表格样式及属性  
          var row = $("#source").clone();  
          //将数值填充至表格中  
          row.find("#rnum").text(r.rnum)  
          row.find("#as_number").text(r.as_number);  
          row.find("#as_name").text(r.as_name);  
          row.find("#as_idcard").text(r.as_idcard);  
          //将此行添加到表格中  
          row.appendTo("#datasource");  
      });  
      // 移除第一行，因为它只有样式没有数据  
      $("#datasource").children("tr:first").remove();  
  }  

jsp页面

  <TR bgColor="#F7F7F7">
            <TD width=9% height="29" align=center class=font_black>序号</TD>
            <TD width=16% align=center class=font_black>营业员编号</TD>
            <TD width=18% align=center class=font_black>营业员姓名</TD>
            <TD width=26% align=center class=font_black>身份证号码</TD>
            <TD width=31% align=center class=font_black>操作</TD>
  </TR>
     <tbody id="datasource">
	  <TR bgColor=#ffffff id="source">
            <TD height="27" id="rnum" align=center class="font_black22"></TD>
            <TD class="cs"  id="as_number"  valign=center class="font_black22"> </TD>
            <TD align=center id="as_name" class="font_black22"></TD>
             <TD align=center id="as_idcard" class="font_black22"> </TD>
             <TD align=center class="font_black22">
               <a href="s_regsucca.jsp">修改信息
               <a href="updatesucess.jsp"   onclick="javascript:if(!confirm('警告：执行此操作将删除数据库中已存在的所有营业员信息，您确定要删除吗？'))return false;return true;">删除信息</TD>
          </TR>
     </tbody>




 <form action="assInfoList.do" name="listpage"> 
        <input type="button" value="首页" onClick="firstpage()"> 
	 <input type="button" value="上一页" onClick="prepage()"> 
	 第<input type="text"  id="pagenumber" name="pagenumber">页 	 
	  共<SPAN id="myspan"></SPAN>页 
	 <input type="button" value="下一页" onClick="nextpage()"> 
 </form>