DAO 層
package DAO;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.ArrayList;
import java.util.List;
import Util.DBManager;
import Entity.Userinfo;
public class getuser {
private ResultSet rst=null;
private PreparedStatement pst=null;
private Connection conn=null;
DBManager dbmanager=new DBManager();
List<Userinfo> userlist=new ArrayList<Userinfo>();
int pageSize=5;//每頁的記錄數
int rowCount=0;//記錄總行數
int pageCount=0;//頁數
public List<Userinfo> getalluser(int pageNow)//傳入一個(參數)當前頁數，返回對應的pageSize(這裏是5,可以設置)條結果
{
conn=dbmanager.getConn();
Userinfo user=null;
try {
String sql="select top "+pageSize+" * from myinfo where id not in(select top "+pageSize*(pageNow-1)+" id from myinfo)";//返回當前頁對應的記錄數
pst=conn.prepareStatement(sql);//將SQL語句加入預編譯
rst= pst.executeQuery();//執行返回結果集
while(rst.next())//循環
{
user=new Userinfo();//將結果封裝到實體類
user.setId(rst.getInt(1));//獲取從數據庫查到的對應的字段
user.setUsername(rst.getString(2));//獲取從數據庫查到的對應的字段
user.setUserpass(rst.getString(3));//獲取從數據庫查到的對應的字段
userlist.add(user);//循環將封裝後的實體添加到lists
}
} catch (Exception e) {
e.printStackTrace();
}
finally
{
dbmanager.closeAll(conn, pst, rst);//關閉連接
}
return userlist;//返回當前頁對應的所有數據(經過封裝後的ResultSet記錄)
}
public int pageCount()//通過總記錄數計算出總頁數並返回出去
{
conn= dbmanager.getConn();
try {
String sql="select count(*) from myinfo";//返回數據庫的總記錄數(總行數)
pst=conn.prepareStatement(sql);
rst=pst.executeQuery();
if(rst.next())//單條記錄用if，多條記錄循環用while
{
rowCount= rst.getInt(1);//計算總的記錄條數
}
if(rowCount/pageSize==0)//總行數/每頁的行數=頁數
{
pageCount=rowCount/pageSize;//頁數
}
else
{
pageCount=rowCount/pageSize+1;//頁數+1(有多餘的則頁數加1)
}
} catch (Exception e) {
e.printStackTrace();
}
finally
{
dbmanager.closeAll(conn, pst, rst);//關閉連接
}
return pageCount;
}
}
Entity 層
package Entity;
public class Userinfo {
private int id;
public Userinfo() {
}
public Userinfo(int id, String username, String userpass) {
this.id = id;
this.username = username;
this.userpass = userpass;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getUserpass() {
return userpass;
}
public void setUserpass(String userpass) {
this.userpass = userpass;
}
private String username;
private String userpass;
}
Util層
package Util;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
public class DBManager {
private static final String driver = "com.microsoft.sqlserver.jdbc.SQLServerDriver";
private static final String url = "jdbc:sqlserver://localhost:1433;DatabaseName=userinfo";
private static final String user = "sa";
private static final String pwd = "123456";
Connection conn = null;
public Connection getConn() {
try {
Class.forName(driver);
conn = DriverManager.getConnection(url, user, pwd);
System.out.println("驅動連接成功");
} catch (Exception e) {
e.printStackTrace();
}
return conn;
}
public void closeAll(Connection conn, Statement sm, ResultSet rs) {
try {
if (rs != null) {
rs.close();
rs = null;
}
if (sm != null) {
sm.close();
sm = null;
}
if (conn != null) {
conn.close();
conn = null;
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
index.jsp 頁面
<%@page import="Entity.Userinfo"%>
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%@ page import="DAO.getuser"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">
<title>My JSP 'index.jsp' starting page</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
</head>
<body>
<h3>jsp記錄分頁效果</h3>
<%
int pageNow=1;//初始化第一頁記錄
getuser dao=new getuser();
String getpageNow=request.getParameter("pageNow");
if(getpageNow!=null)//獲取點擊傳入的頁數(當前頁)
{
pageNow=Integer.parseInt(getpageNow);
}
List userlist= dao.getalluser(pageNow ); //獲取當前頁面對應的記錄
%>
<table>
<tr>
<td>用戶編號:</td>
<td>用戶名:</td>
<td>密碼:</td>
</tr>
<%
for(int i=0;i<userlist.size();i++)//循環打印
{
Userinfo user=(Userinfo)userlist.get(i);//循環打印
%>
<tr>
<td><%=user.getId()%></td>
<td><%=user.getUsername()%></td>
<td><%=user.getUserpass()%></td>
</tr>
<%
}
%>
</table>
<%
int pageCount=dao.pageCount();//通過SQL語句獲取所有的記錄頁面
if(pageNow!=1)
{
out.print("<a href=index.jsp?pageNow="+(pageNow-1)+">上一頁</a>");
}
out.print("<a href=index.jsp?pageNow="+1+">首頁</a>");
for(int i=1;i<pageCount;i++)
{
out.print("<a href=index.jsp?pageNow="+i+">["+i+"]</a>");
}
out.print("<a href=index.jsp?pageNow="+pageCount+">尾頁</a>");
if(pageNow!=pageCount)
{
out.print("<a href=index.jsp?pageNow="+(pageNow+1)+">下一頁</a>");
}
%>
</body>
</html>
