java连接oracle_11g分页显示记录

    记录学习的脚步

       使用jdbc方式连接oracle数据库,然后分页显示scott用户的emp表中的记录

  其中 让人比较费劲的就是oracle的分页查询 需要用到子查询和rownum

        rownum是按记录的插入顺序生成的行编号,默认情况下为1,所以只有进行小于操作的时候,rownum才有意义

而对于rownum的详细详解 参看这位老兄写的 http://www.cnblogs.com/zjrstar/archive/2006/08/31/491090.html

 

 

index.jsp的代码

<%@page import="com.undergrowth.EmpBean"%>
<%@page import="java.sql.ResultSet"%>
<%@page import="java.sql.PreparedStatement"%>
<%@page import="com.undergrowth.ConnDB"%>
<%@page import="java.sql.Connection"%>
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%
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>
  <center>
   <%
   int pageNow=1;
   String s_pageNow=request.getParameter("pageNow");
   if(s_pageNow!=null) pageNow=Integer.parseInt(s_pageNow); 
   
   int pageSize=3; //每一页显示多少条记录
   int rowCount=ConnDB.getRowCount(); //总共有多少行
   int pageCount=0; //总共有多少页
   //获取总共有多少页
  if(rowCount%pageSize==0) {
  	pageCount=rowCount/pageSize;
  }else {
  	pageCount=rowCount/pageSize+1;
  }
   
  	ArrayList<EmpBean> alBeans=ConnDB.getAllRecord(pageNow,pageSize);
   if(alBeans.size()>0){
   out.print("<table align='center' border=1>"+
   "<caption>雇员信息表</caption>"+"<tr><th>编号</th><th>姓名</th><th>工作</th><th>领导</th><th>雇佣日期</th><th>薪水</th><th>补贴</th><th>部门编号</th></tr>");
   	//显示记录
   	for(EmpBean bean:alBeans)
   	{
   		out.print("<tr>");
   		out.print("<td>"+bean.getEmpno()+"</td>");
   		out.print("<td>"+bean.getEname()+"</td>");
   		out.print("<td>"+bean.getJob()+"</td>");
   		out.print("<td>"+bean.getMgr()+"</td>");
   		out.print("<td>"+bean.getHiredate()+"</td>");
   		out.print("<td>"+bean.getSal()+"</td>");
   		out.print("<td>"+bean.getComm()+"</td>");
   		out.print("<td>"+bean.getDeptno()+"</td>");
   		out.print("</tr>");
   	}
   	
   	out.print("<tr align='center'>");
   	out.print("<td colspan=8>");
   	//显示上一页
   	if(pageNow!=1) out.print("[<a href=index.jsp?pageNow="+(pageNow-1)+">上一页</a>]");
   	for(int i=1;i<=pageCount;i++)
   	{
   		
   		out.print("[<a href=index.jsp?pageNow="+i+">"+i+"</a>]");
   		
   	}
   	//显示下一页
   	if(pageNow!=pageCount) out.print("[<a href=index.jsp?pageNow="+(pageNow+1)+">下一页</a>]");
   	out.print("</td>");
   	out.print("</tr>");
   	 out.print("</table>");
   }
    %>
    
    </center>
  </body>
</html>


 

用于连接数据库的ConnDB.java

package com.undergrowth;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;

public class ConnDB {
	
	private static String driverName="oracle.jdbc.driver.OracleDriver";
	private static String url="jdbc:oracle:thin:@localhost:1521:under";
	private static String user="scott";
	private static String password="scott";
	private static Connection connection=null;
	private static PreparedStatement ps=null;
	private static ResultSet rs=null;
	
	public static Connection getConnection()
	{
		try {
			//注册驱动
			Class.forName(driverName);
			//建立连接
			connection=DriverManager.getConnection(url, user, password);
		} catch (Exception e) {
			e.printStackTrace();
		}
		
		return connection;
	}
	
	public static int getRowCount()
	{
		int rowCount=0;
		connection=getConnection();
		   //获取到员工表中有多少条记录
		   String sql="select count(*) from emp";
		try {
			ps = connection.prepareStatement(sql);
			rs=ps.executeQuery();
			   if(rs.next()){
			   		rowCount=Integer.parseInt(rs.getString(1));
			   }
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}finally{
			closeRes(rs, ps, connection);
		}
		
		return rowCount;   
	}
	
	public static ArrayList<EmpBean> getAllRecord(int pageNow,int pageSize)
	{
		ArrayList<EmpBean> alBeans=new ArrayList<EmpBean>();
		try {
			connection=getConnection();
			//String sql="select * from emp where rownum<="+pageNow*pageSize + "and rownum>="+(pageNow-1)*pageSize+1;
			String sql="select a2.* from (select a1.*,rownum rn from (select * from emp) a1 where rownum<="+pageNow*pageSize+") a2 where a2.rn>="+((pageNow-1)*pageSize+1);
			//System.out.println(sql);
			ps=connection.prepareStatement(sql);
			rs=ps.executeQuery();
			while(rs.next())
			{
				EmpBean empBean=new EmpBean();
				empBean.setEmpno(rs.getString(1));
				empBean.setEname(rs.getString(2));
				empBean.setJob(rs.getString(3));
				empBean.setMgr(rs.getString(4));
				empBean.setHiredate(rs.getDate(5));
				empBean.setSal(rs.getFloat(6));
				empBean.setComm(rs.getFloat(7));
				empBean.setDeptno(rs.getString(8));
				alBeans.add(empBean);
			}
		} catch (Exception e) {
			// TODO: handle exception
		}
		return alBeans;
	}
	
	public static void closeRes(ResultSet rs,PreparedStatement ps,Connection connection)
	{
		if(rs!=null)
			try {
				rs.close();
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		if(ps!=null)
			try {
				ps.close();
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		if(connection!=null)
			try {
				connection.close();
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
	}
	
}


 

辅助Bean EmpBean.java

package com.undergrowth;

import java.util.Date;

public class EmpBean {
	private String empno;
	public String getEmpno() {
		return empno;
	}
	public void setEmpno(String empno) {
		this.empno = empno;
	}
	public String getEname() {
		return ename;
	}
	public void setEname(String ename) {
		this.ename = ename;
	}
	public String getJob() {
		return job;
	}
	public void setJob(String job) {
		this.job = job;
	}
	public String getMgr() {
		return mgr;
	}
	public void setMgr(String mgr) {
		this.mgr = mgr;
	}
	public Date getHiredate() {
		return hiredate;
	}
	public void setHiredate(Date hiredate) {
		this.hiredate = hiredate;
	}
	public Float getSal() {
		return sal;
	}
	public void setSal(Float sal) {
		this.sal = sal;
	}
	public Float getComm() {
		return comm;
	}
	public void setComm(Float comm) {
		this.comm = comm;
	}
	public String getDeptno() {
		return deptno;
	}
	public void setDeptno(String deptno) {
		this.deptno = deptno;
	}
	private String ename;
	private String job;
	private String mgr;
	private Date hiredate;
	private Float sal;
	private Float comm;
	private String deptno;
}


 

测试效果

输入: http://localhost:8080/PagingOracle/

效果:

 

posted on 2013-09-22 16:40  liangxinzhi  阅读(285)  评论(0编辑  收藏  举报