我正在从cassandra数据库中读取数据并在jqGrid中显示。但它在所有页面上显示相同的记录。我使用的是http://javahunter.wordpress.com/2010/12/07/jqgrid-example/
中的代码这是我的JSP文件 -
enter code here
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
"http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>JQGrid Special</title>
<!-- JAVASCRIPT FILES -->
<script src="thirdparty/jqgrid/jquery-1.3.1.js" type="text/javascript"></script>
<script src="thirdparty/jqgrid/jquery-ui-1.7.2.custom.min.js" type="text/javascript">
</script>
<script src="thirdparty/jqgrid/jquery.layout.js" type="text/javascript"></script>
<script src="thirdparty/jqgrid/i18n/grid.locale-en.js" type="text/javascript"></script>
<script src="thirdparty/jqgrid/jquery.jqGrid.min.js" type="text/javascript"></script>
<script src="thirdparty/jqgrid/jquery.tablednd.js" type="text/javascript"></script>
<script src="thirdparty/jqgrid/jquery.contextmenu.js" type="text/javascript"></script>
<script src="thirdparty/jQueryPlugins/jQueryJsonPlugin/jquery.json-2.2.js"
type="text/javascript"></script>
<script src="js/guestUser.js" type="text/javascript"></script>
<script src="js/modifyForm.js" type="text/javascript"></script>
<script src="js/addForm.js" type="text/javascript"></script>
<script src="js/commonFunctions.js" type="text/javascript"></script>
<script src="js/deleteRow.js" type="text/javascript"></script>
<script src="thirdparty/genPassword.js" type="text/javascript"></script>
<script src="thirdparty/jQueryPlugins/jQueryValidationplugin/jquery.validate.js"
type="text/javascript"></script>
<script src="thirdparty/jQueryPlugins/jQueryValidationplugin/jquery.validationEngine.js"
type="text/javascript"></script>
<script src="thirdparty/jQueryPlugins/jQuerycustomalertsPlugin/jquery.alerts.js"
type="text/javascript"></script>
<script
src="thirdparty/jQueryPlugins/jQuerytextLimiterPlugin/jquery.inputlimiter.1.1.1.js"
type= "text/javascript"></script>
<!-- CSS FILES -->
<link rel="stylesheet" type="text/css" media="screen"
href="thirdparty/jQueryPlugins/jQuerycustomalertsPlugin/jquery.alerts.css" />
<link rel="stylesheet" type="text/css" media="screen"
href="thirdparty/jQueryPlugins/jQuerytextLimiterPlugin/jquery.inputlimiter.1.0.css" />
<link rel="stylesheet" type="text/css" media="screen"
href="thirdparty/jqgrid/css/themes/redmond/jquery-ui-1.7.1.custom.css" />
<link rel="stylesheet" type="text/css" media="screen" href="css/gugrid.css" />
<link rel="stylesheet" type="text/css" media="screen"
href="thirdparty/jqgrid/css/ui.jqgrid.css" />
<link rel="stylesheet" type="text/css" media="screen"
href="thirdparty/jQueryPlugins/jQueryValidationplugin/validationEngine.jquery.css" />
<script>
function fillGridOnEvent(){
$("#jQGrid").html("<table id=\"list\"></table><div id=\"page\"></div>");
jQuery("#list").jqGrid({
url:'<%=request.getContextPath()%>/JQGridServlet?q=1&action=fetchData',
datatype: "xml",
height: 250,
colNames:['Sr. No.','Student Name','Student Std.','Student RollNo.',"Action"],
colModel:[
{name:'srNo',index:'srNo', width:90,sortable:true},
{name:'stdName',index:'stdName', width:130,sortable:false},
{name:'stdStd',index:'stdStd', width:100,sortable:false},
{name:'stdRollNo',index:'stdRollNo', width:180,sortable:false},
{name:'view',index:'view', width:100,sortable:false}
],
multiselect: false,
paging: true,
rowNum:20,
rowList:[10,20,30],
pager: "#page",
loadonce:false,
recordtext:"View {0} - {1} of {10}",
caption: "Student Details"
}).navGrid('#page',{edit:false,add:false,del:false});
}
jQuery().ready(function (){
//fillGrid();
alert("ready");
});
</script>
</head>
<body onload="fillGridOnEvent();">
<div id="jQGrid" align="center">
</div>
</body>
</html>
这是我的servlet文件 -
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class JQGridServlet extends HttpServlet {
protected void processRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
PrintWriter out = response.getWriter();
try {
if (request.getParameter("action").equals("fetchData")) {
response.setContentType("text/xml;charset=UTF-8");
String status = request.getParameter("status");
String rows = request.getParameter("rows");
String page = request.getParameter("page");
int totalPages = 0;
int totalCount = 150;
if (totalCount > 0) {
if (totalCount % Integer.parseInt(rows) == 0) {
totalPages = totalCount / Integer.parseInt(rows);
} else {
totalPages = (totalCount / Integer.parseInt(rows)) + 1;
}
} else {
totalPages = 0;
}
System.out.println(totalPages);
out.print("<?xml version='1.0' encoding='utf-8'?>\n");
out.print("<rows>");
out.print("<page>" + request.getParameter("page") + "</page>");
out.print("<total>" + totalPages + "</total>");
out.print("<records>" + 150 + "</records>");
int srNo = 1;
for (int i=0;i<150;i++) {
out.print("<row id='" + i + "'>");
out.print("<cell>" + srNo + "</cell>");
out.print("<cell>Taher</cell>");
out.print("<cell>8th</cell>");
out.print("<cell>25</cell>");
out.print("<cell><![CDATA[<a href='ViewStd.jsp'>View</a>]]></cell>");
out.print("</row>");
srNo++;
}
out.print("</rows>");
}
} finally {
out.close();
}
}
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
@Override
public String getServletInfo() {
return "Short description";
}
}
答案 0 :(得分：0)
在Servlet中创建响应时，您应该只在页面中包含应显示的行，而不是所有行。
所以不要返回所有行：
for (int i = 0; i < totalRecords; i++) {
printRecord(i);
}
您应该只返回必需的行：
int firstRecord = (pageNumber - 1) * rowsPerPage;
int lastRecord = Math.min(firstRecord + rowsPerPage, totalRecords);
for (int i = firstRecord; i < lastRecord; i++) {
printRecord(i);
}
注意：有“pageNumber-1”，因为页码从1开始，而不是从0开始。“Math.min”就在那里，因为 last 页面的行数可能少于所需数量;例如，如果你想要每页10行，并且总共有32行记录，前三页将包含10行，但第四页只有2行。
顺便说一下，您链接的页面上还有另一个错误。确定“totalPages”的正确公式应该不：
totalPages = (totalRecords / rowsPerPage) + 1;
但是：
totalPages = (totalRecords + rowsPerPage - 1) / rowsPerPage;
为什么呢？如果总共有30条记录，并且每页需要10行，那么它只有3页，而不是文章中的4页。只有31个或更多记录，您需要4页。