一个分页的类及调用的例子_MySQL

　　
//PageCt.java 分页的类
/*
*** @version ***********
*** Created on 2001年6月25日, 下午14:41
**************************************
*/
package vod;
import java.sql.*;
import java.util.*;



public class PageCt
{
private long l_start; //开始纪录
private long l_end; //结束纪录
private long l_curpage; //当前页数
private long l_totalnum;//总记录数
private int int_num=5; //每页10条
private long l_totalpage; //总的页数



public void Init(long currentpage,long totalnum)
{
l_curpage = currentpage;
l_totalnum = totalnum;



if (currentpage>=0)
{
if (currentpage>=(long)Math.ceil((double)l_totalnum/(double)int_num))
l_curpage = (long)Math.floor((double)l_totalnum/(double)int_num);
else
l_curpage = currentpage;
}
else
{
l_curpage = 0;
}
l_start = l_curpage * int_num;
l_end = l_start + int_num;
if (l_end > l_totalnum)
l_end = l_totalnum;
l_totalpage = (long)Math.ceil((double)l_totalnum/(double)int_num);
}
public long getCurpage()
{
return l_curpage;
}
public long getPrepage()
{
if (l_curpage-1>=0)
{
return l_curpage-1;
}
else
{
return 0;
}
}
public long getNextpage()
{
if (l_curpage+1<=l_totalpage)
{
return l_curpage+1;
}
else
{
return l_totalpage;
}
}
public long getTotalnum()
{
return l_totalnum;
}
public long getTotalpage()
{
return l_totalpage;
}
public long getStart()
{
return l_start;
}
public long getEnd()
{
return l_end;
}



};
===============================================
//调用例子
<%
/*
*** @author 马毅 ***********
*** @version ***********
*** Created on 2001年6月12日, 下午17:13
**************************************
*/
<%@ page import="java.sql.*"%>
<%@ page import="java.lang.*"%>
<%@ page contentType="text/html;charset=gb2312" %>

Test for Test

---

<%
ResultSet rs0 = sqlbean.executeQuery("select count(*) from UserList );
rs0.next();
long data_num=rs0.getLong(1);
long Current_Page = 0;
String currentpage=(String)request.getParameter("currentpage");
if (currentpage != null && !currentpage.equals(""))
{
Current_Page = Integer.parseInt(request.getParameter("currentpage"));
}
String Query_Page=(String)request.getParameter("Query_Page");
if (Query_Page!=null && !Query_Page.equals(""))
{
Current_Page = Integer.parseInt(request.getParameter("Query_Page"))-1;
}
PageCt.Init(Current_Page,data_num);
long l_start = PageCt.getStart();
long l_end = PageCt.getEnd();
//查询记录
ResultSet rs = sqlbean.executeQuery("select * from UserList " );
long i=0;
while((i{
i++;
}
//输出查询结果
long j=0;
while(rs.next() && (i{
j=i+1;
String col2 = rs.getString(2);
String col3 = rs.getString(3);
String col4 = rs.getString(4);
String col5 = rs.getString(5);
String col6 = rs.getString(6);
String col7 = rs.getString(7);
String col8 = rs.getString(8);
//打印所显示的数据
out.println("");
out.println("");
out.println("");
out.println("");
if (col8!=null && !col8.equals(""))
{
out.println("");
}
out.println("

" + j + "、"+(col2==null?"":col2)+"
答案："+(col3==null?"":col3)+"
选项1："+(col4==null?"":col4)+"	选项2："+(col5==null?"":col5)+"
选项3："+(col6==null?"":col6)+"	选项4："+(col7==null?"":col7)+"
备注："+col8+"

");
i++;
}
%>







添加