Pagination with condition using servlet or jsp

Hi, Thanks in advance. I have a requirement like this,

In front-end page I have one text box and one submit button, After clicking the submit button that form field value I retrieved using "String name=request.getParameter("name of that text box")", Then I want perform the pagination based on the string value(I mean pagination with condition). My problem is first time five records will come(I mean 5 records per page) after clicking the 2 page that page will be reload that time "name variable will become null" finally result will come null only (Totally matched records i have 25 based on the condition) and I found one problem in that when I am trying to click 2 page onwords that time name variable will become null. How to make it that name variable constant.

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December 10, 2012 at 3:08 PM

Here is jsp code that retrieves the record from database and show pagination.

paging.jsp:

<%@ page import="java.sql.*" %>
<%!
public int nullIntconvert(String str){
int num=0;
if(str==null){
str="0";
}
else if((str.trim()).equals("null")){
str="0";
}
else if(str.equals("")) {
str="0";
}
try{
num=Integer.parseInt(str);
}
catch(Exception e){ }
return num;
}
%>
<%
Class.forName("com.mysql.jdbc.Driver").newInstance();
Connectionconn = DriverManager.getConnection("jdbc:mysql://localhost:3306/db2admin","root", "root");
 int showRows=5;
int totalRecords=5;
int totalRows=nullIntconvert(request.getParameter("totalRows"));
int totalPages=nullIntconvert(request.getParameter("totalPages"));
int iPageNo=nullIntconvert(request.getParameter("iPageNo"));
int cPageNo=nullIntconvert(request.getParameter("cPageNo"));
int startResult=0;
int endResult=0;
if(iPageNo==0){
iPageNo=0;
}
else{
iPageNo=Math.abs((iPageNo-1)*showRows);
}
String query1="SELECT SQL_CALC_FOUND_ROWS * FROM db2admin.reg limit "+iPageNo+","+showRows+"";
PreparedStatement ps1=conn.prepareStatement(query1);
ResultSet rs1=ps1.executeQuery();

String query2="SELECT FOUND_ROWS() as cnt";
PreparedStatement ps2=conn.prepareStatement(query2);
ResultSet rs2=ps2.executeQuery();
if(rs2.next()){
totalRows=rs2.getInt("cnt");
}
%>
<html><h3>Pagination of JSP page</h3>
<body><form>
<input type="hidden" name="iPageNo" value="<%=iPageNo%>">
<input type="hidden" name="cPageNo" value="<%=cPageNo%>">
<input type="hidden" name="showRows" value="<%=showRows%>">
<table width="100%" cellpadding="0" cellspacing="0" border="1" >
<tr>
<th>USERNAME</th><th>FIRSTNAME</th><th>EMAIL</th><th>COUNTRY</th>
</tr>
<%while(rs1.next()){
%>
<tr><td><%=rs1.getString("USERNAME")%></td>
<td><%=rs1.getString("FIRSTNAME")%></td>
<td><%=rs1.getString("EMAIL")%></td>
<td><%=rs1.getString("COUNTRY")%></td>
</tr>
<%}%>
<%try{
if(totalRows<(iPageNo+showRows)){
endResult=totalRows;
}
else{
endResult=(iPageNo+showRows);
}
startResult=(iPageNo+1);
totalPages=((int)(Math.ceil((double)totalRows/showRows)));
}
catch(Exception e){
e.printStackTrace();
}
%>
<tr><td colspan="3">
<div>
<%
int i=0;
int cPage=0;
if(totalRows!=0){
cPage=((int)(Math.ceil((double)endResult/(totalRecords*showRows))));
int prePageNo=(cPage*totalRecords)-((totalRecords-1)+totalRecords);
if((cPage*totalRecords)-(totalRecords)>0){
%>
<a href="paging.jsp?iPageNo=<%=prePageNo%>&cPageNo=<%=prePageNo%>">Previous</a>
<%
}
for(i=((cPage*totalRecords)-(totalRecords-1));i<=(cPage*totalRecords);i++){
if(i==((iPageNo/showRows)+1)){%>
<a href="paging.jsp?iPageNo=<%=i%>" style="cursor:pointer;color: red"><b><%=i%></b></a>
<%
}
else if(i<=totalPages){
%>
<a href="paging.jsp?iPageNo=<%=i%>"><%=i%></a>
<%
}
}
if(totalPages>totalRecords && i<totalPages){
%>
<a href="paging.jsp?iPageNo=<%=i%>&cPageNo=<%=i%>">Next</a>
<%
}
}
%>
<b>Rows <%=startResult%> - <%=endResult%> Total Rows <%=totalRows%> </b>
</div></td></tr></table></form></body></html>