jsp+servlet+javabean实现数据分页方法完整实例

本文实例讲述了jsp+servlet+javabean实现数据分页方法。分享给大家供大家参考，具体如下：

这里秉着且行且记的心态，记录下学习过程，学得快忘得快，生怕遗忘，以备日后使用。
用到的部分代码是自己在网上查找，并自己修改，加上自己的理解。也不知道算不算原创，只做自己学习记录。

使用相关：postgresql数据库、dom4j、jsp、servlet

一、首先是工程格局，来个全局视图方便读者与自己查看与使用

思路为：

以config.xml文件记录配置信息，以方便数据库更改，方便移植与重用。
dom4jutil.java用于解析xml属性文件以获得需要数据
postgresql_util.java分装数据连接与数据库操作
pageproperties.java为表格分页属性javabean
pageproperties.java封装分页操作
page.java为分页主要操作
tablepage.jsp为效果显示界面

用到的第三方jar包：

dom4j-1.6.1.jar用于xml文件解析
postgresql-9.3-1101.jdbc4.jar用于jdbc连接postgresql数据库

分页效果如下：能通过点击上页下页实现翻页，输入指定页面跳转(超出范围跳转到第1或最后页)。具体实现请参见详细代码，我都贴上来了。小菜鸟一名，处于正在学习阶段，有大神能指点下当然更好，希望不吝赐教！

二、具体代码实现

1、config.xml数据库连接信息属性文件

<?xml version="1.0" encoding="utf-8"?>
<!doctype postgres[
 <!element postgres (driver,url,username,pwd)>
 <!element driver (#pcdata)>
 <!element url (#pcdata)>
 <!element username (#pcdata)>
 <!element pwd (#pcdata)>
]>
<postgres>
 <driver>org.postgresql.driver</driver>
 <url>jdbc:postgresql://localhost:5432/java</url>
 <username>admin</username>
 <pwd>k42jc</pwd>
</postgres>

2、dom4jutil.java

package util;
import org.dom4j.document;
import org.dom4j.documentexception;
import org.dom4j.element;
import org.dom4j.io.saxreader;
/** 
 * 用于解析xml属性文件 
 * @author johsonmuler 
 * 
 */
public class dom4jutil {
 private static element root=null;
 static{//静态代码块
  //创建解析对象
  saxreader sr=new saxreader();
  //获取当前工程路径
//  string url=system.getproperty("user.dir");
  string url=dom4jutil.class.getresource("").getpath();
//  system.out.println(url);
  try {
   //通过文件路径获取配置文件信息
   document doc=sr.read(url+"config.xml");
   //获取根节点
   root=doc.getrootelement();
  } catch (documentexception e) {
   e.printstacktrace();
  }
 }
 public static string getpostgresdata(string str){
  //以根节点为基础，获取配置文件数据
  element e=root.element(str);
  string data=e.gettext();
  return data;
 }
 public static void main(string[] args) {
//  string url=dom4jutil.class.getresource("..").getpath();
//  system.out.println(system.getproperty("user.dir"));
//  system.out.println(url);
  string driver=getpostgresdata("driver");
  string url=getpostgresdata("url");
  system.out.println(driver);
  system.out.println(url);
 }
}

3、postgresql_util.java

package util;
import java.sql.preparedstatement;
import java.sql.statement;
import java.sql.connection;
import java.sql.drivermanager;
import java.sql.resultset;
import java.sql.sqlexception;
import java.util.list;
public class postgresql_util {
 private static dom4jutil dom=new dom4jutil();
 private static connection c=null;
 private static resultset rs=null;
 private static string driver=dom.getpostgresdata("driver");
 private static string url=dom.getpostgresdata("url");
 private static string username=dom.getpostgresdata("username");
 private static string pwd=dom.getpostgresdata("pwd");
 public postgresql_util(){
  try {
   class.forname(driver);
   c=drivermanager.getconnection(url);
  } catch (classnotfoundexception e) {
   system.out.println("未找到指定类："+e.getmessage());
  } catch (sqlexception e) {
   system.out.println("获取连接异常："+e.getmessage());
  }
 }
 /**
  * 数据查询方法(statement)
  * @param sql
  * @return
  * @throws sqlexception
  */
 public resultset executequery(string sql) throws sqlexception{
  statement s=c.createstatement();
  rs=s.executequery(sql);
  return rs;
 }
 /**
  * 重载方法(preparedstatement)
  * @param sql
  * @param list
  * @return
  * @throws sqlexception
  */
 public resultset executequery(string sql,list<object> list) throws sqlexception{
  preparedstatement ps=c.preparestatement(sql);
  for(int i=0;i<list.size();i++){
   system.out.println(list.get(i));
   system.out.println(i+1);
   ps.setobject(i+1, list.get(i));
  }
  rs=ps.executequery();
  c.close();
  return rs;
 }
 /**
  * 数据更新方法(添加，删除，更改)(statement)
  * @param sql
  * @throws sqlexception
  */
 public int executeupdate(string sql) throws sqlexception{
  statement s=c.createstatement();
  int i=s.executeupdate(sql);
  c.close();
  return i;
 }
 /**
  * 重载方法(preparedstatement)
  * @param sql
  * @param list
  * @throws sqlexception
  */
 public int executeupdate(string sql,list<object> list) throws sqlexception{
  preparedstatement ps=c.preparestatement(sql);
  for(int i=0;i<list.size();i++){
   ps.setobject(i+1, list.get(i));
  }
  int i=ps.executeupdate();
  c.close();
  return i;
 }
 /**
  * 单独的获取连接
  * @return
  * @throws classnotfoundexception
  * @throws sqlexception
  */
 public static connection getconnection() throws classnotfoundexception, sqlexception{
  class.forname(driver);
  c=drivermanager.getconnection(url);
  return c;
 }
}

4、pageproperties.java

package bean;
import java.sql.resultset;
public class pageproperties {
 private int currentpage;//当前页号
 private int totalpages;//总页数
 private int totalrecords;//总数据条数
 private resultset rs;//动态结果集
 public pageproperties() {
  super();
 }
 public pageproperties(int currentpage, int totalpages, int totalrecords, 
   resultset rs) {
  super();
  this.currentpage = currentpage;
  this.totalpages = totalpages;
  this.totalrecords = totalrecords;
  this.rs = rs;
 }
 public int getcurrentpage() {
  return currentpage;
 }
 public void setcurrentpage(int currentpage) {
  this.currentpage = currentpage;
 }
 public int gettotalpages() {
  return totalpages;
 }
 public void settotalpages(int totalpages) {
  this.totalpages = totalpages;
 }
 public int gettotalrecords() {
  return totalrecords;
 }
 public void settotalrecords(int totalrecords) {
  this.totalrecords = totalrecords;
 }
 public resultset getrs() {
  return rs;
 }
 public void setrs(resultset rs) {
  this.rs = rs;
 }
}

5、tablepage.java

package bean;
import java.sql.resultset;
public class pageproperties {
 private int currentpage;//当前页号
 private int totalpages;//总页数
 private int totalrecords;//总数据条数
 private resultset rs;//动态结果集
 public pageproperties() {
  super();
 }
 public pageproperties(int currentpage, int totalpages, int totalrecords, 
   resultset rs) {
  super();
  this.currentpage = currentpage;
  this.totalpages = totalpages;
  this.totalrecords = totalrecords;
  this.rs = rs;
 } 
 public int getcurrentpage() {
  return currentpage;
 }
 public void setcurrentpage(int currentpage) {
  this.currentpage = currentpage;
 }
 public int gettotalpages() {
  return totalpages;
 }
 public void settotalpages(int totalpages) {
  this.totalpages = totalpages;
 }
 public int gettotalrecords() {
  return totalrecords;
 }
 public void settotalrecords(int totalrecords) {
  this.totalrecords = totalrecords;
 }
 public resultset getrs() {
  return rs;
 }
 public void setrs(resultset rs) {
  this.rs = rs;
 }
}

6、page.java这是主要处理类，servlet

package servlet;
import java.io.ioexception;
import java.io.printwriter;
import java.sql.resultset;
import java.sql.sqlexception;
import javax.servlet.servletexception;
import javax.servlet.http.httpservlet;
import javax.servlet.http.httpservletrequest;
import javax.servlet.http.httpservletresponse;
import util.postgresql_util;
import bean.pageproperties;
import bean.tablepage;
public class page extends httpservlet {
 public void service(httpservletrequest request, httpservletresponse response)
   throws servletexception, ioexception {
  request.setcharacterencoding("utf-8");
  response.setcontenttype("text/html;charset=utf-8");
  printwriter out = response.getwriter();
  /**
   * 通过tablepage设置分页属性
   *
   */
  tablepage tb=new tablepage();
  //获取当前表格显示的页码
  int currentpage=tb.currentpage(tb.getstrpage(request, "page"));
  system.out.println(currentpage);
  //设置每页显示数据条数
  tb.setpagerecord(10);//设置每页显示10条数据
  /**
   * 通过xxsql_util设置jdbc连接及数据处理
   */
  postgresql_util postgres=new postgresql_util();
  try {
   resultset rs_count=postgres.executequery("select count(*) as c from student");
   rs_count.next();
   //获得总的数据条数
   int totalrecords=rs_count.getint("c");
   //根据数据表的总数据条数获取页面显示表格的总页数
   int totalpages=tb.gettotalpages(totalrecords);
   if(currentpage>totalpages){
    currentpage=totalpages;//保证最后一页不超出范围
   }
   //根据数据库表信息和当前页面信息获得动态结果集
   resultset rs=tb.getpageresultset(postgres.executequery("select * from student"), currentpage);
   /** 
    * 将数据加入javabean
    */
   pageproperties pp=new pageproperties(currentpage, totalpages, totalrecords, rs);
   /** 
    * 将javabean转发至前端 
    */ 
   request.setattribute("result", pp);
   request.getrequestdispatcher("tablepage.jsp").forward(request, response);
  } catch (sqlexception e) {
   system.out.println("class page:"+e.getmessage());
//   e.printstacktrace();
  }
 }
}

7、tablepage.jsp前台显示效果

<%@ page language="java" import="java.util.*" pageencoding="utf-8"%>
<%@page import="java.sql.resultset"%>
<%@page import="bean.pageproperties"%>
<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<%
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>
 <title>简单数据分页</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>
 <table>
  <tr>
   <td>姓名</td>
   <td>性别</td>
   <td>年龄</td>
   <td>分数</td>
  </tr>
  <%
   pageproperties pp=(pageproperties)request.getattribute("result"); 
   resultset rs=pp.getrs();
  %>
  <%
   int i=1;
   while(rs.next()){
   %>
  <tr>
   <td><%=rs.getobject(1) %></td>
   <td><%=rs.getobject(2) %></td>
   <td><%=rs.getobject(3) %></td>
   <td><%=rs.getobject(4) %></td>
  </tr>
  <%
   i++;
   if(i>10)
    break;
  }
   %>
   <br/>
   <span><%=pp.gettotalpages() %>页</span>
  <span>共<%=pp.gettotalrecords() %>条数据</span>
  <span>本页<%=i-1 %>条</span>
  <span>第<%=pp.getcurrentpage() %>页</span>
  <p align="center">
   <%
    if ( pp.getcurrentpage() > 1 )
    {
   %><a href="<%=path %>/page?page=<%=pp.getcurrentpage() - 1%>"><<上一页</a>
   <%
    }
   %>
   <%
    if ( pp.getcurrentpage() < pp.gettotalpages() )
    {
   %><a href="<%=path %>/page?page=<%=pp.getcurrentpage() + 1%>">下一页>></a>
   <%
    }
   %>
   <input type="text" name="input_text" id="input_text" size="1" /> 
   <input type="button" name="skip" id="skip" value="跳转" onclick="skip();"/>
   <script>
    function skip(){
     var v=document.getelementbyid("input_text").value;
     location.href="page?page="+v;
    }
   </script>
  </p>
 </table>
 </body>
</html>

初步看，感觉后台代码实在是繁琐，但这是考虑到程序健壮性与可移植性，方便代码重用。以后要用，根据自己的需要在属性文件（config.xml）中配置相关jdbc驱动，在jsp页面通过request获得后台servlet（page.jsp）的转发结果("result"),结合页面属性(pageproperties.java类)即可实现效果。

当然，这也是因为个人学习，倾向于多用点东西。

希望本文所述对大家jsp程序设计有所帮助。