[移动开发]JSP+Servlet实现分页功能

一、PageBean内容如下

package com.kingming.entity;

import java.util.List;

public class PageBean {
	//当前页
	private int currPage;
	
	//上一页
	private int prePage;
	
	//下一页
	private int nextPage;
	
	//分页条数
	private int limitSize;
	
	//总页
	private int countSize;
	
	//limit 开始位置
	private int startIndex;

	//数据集
	private List data;

	public int getCurrPage() {
		return currPage;
	}

	public void setCurrPage(int currPage) {
		this.currPage = currPage;
	}

	public int getPrePage() {
		return this.currPage>1?this.currPage-1:this.currPage;
	}

	public void setPrePage(int prePage) {
		this.prePage = prePage;
	}

	public int getNextPage() {
		return this.currPage<this.countSize?this.currPage+1:this.currPage;
	}

	public void setNextPage(int nextPage) {
		this.nextPage = nextPage;
	}

	public int getLimitSize() {
		return limitSize;
	}

	public void setLimitSize(int limitSize) {
		this.limitSize = limitSize;
	}

	public int getCountSize() {
		return countSize;
	}

	public void setCountSize(int countSize) {
		this.countSize = countSize%this.limitSize==0?countSize/this.limitSize:countSize/this.limitSize+1;
	}

	public int getStartIndex() {
		return (this.currPage-1)*this.limitSize;
	}
	
	public List getData() {
		return data;
	}

	public void setData(List data) {
		this.data = data;
	}

	public PageBean(String currPage, String limitSize) {
		if(currPage==null){
			this.currPage = 1;
		}else{
			this.currPage = Integer.parseInt(currPage);
		}
		if(limitSize==null){
			this.limitSize = 2;
		}else{
			this.limitSize = Integer.parseInt(limitSize);
		}
	}
}

二、创建Dao层

package com.kingming.dao;

import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;

import javax.naming.NamingException;

import com.kingming.entity.MsgEntity;
import com.kingming.entity.PageBean;

public class MsgDao extends DBUtils{
	/**
	 * 查询所有的短信
	 * @param sendto
	 * @return
	 */
	public List<MsgEntity> getMyMsgList(){
		String sql = "select * from msg";
		ResultSet rs = null;
		List<MsgEntity> list = new ArrayList<MsgEntity>();
		try {
			rs = super.queryResult(sql);
			while(rs.next()){
				list.add(new MsgEntity(rs.getInt(1),rs.getString(2),rs.getString(3),rs.getString(4),rs.getInt(5),rs.getString(6),rs.getString(7)));
			}
			return list;
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (NamingException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		return null;
	}
	
	/**
	 * 查询所有的短信
	 * @param sendto
	 * @return
	 */
	public PageBean getMyMsgListWithPage(PageBean pageBean){
		String sql = "select * from msg limit ?,?";
		ResultSet rs = null;
		List<MsgEntity> list = new ArrayList<MsgEntity>();
		try {
			rs = super.queryResult(sql,pageBean.getStartIndex(),pageBean.getLimitSize());
			while(rs.next()){
				list.add(new MsgEntity(rs.getInt(1),rs.getString(2),rs.getString(3),rs.getString(4),rs.getInt(5),rs.getString(6),rs.getString(7)));
			}
			
			pageBean.setCountSize(this.getMyMsgList().size());
			pageBean.setData(list);
			
			return pageBean;
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (NamingException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		return null;
	}
}

三、创建Biz

package com.kingming.biz;

import java.util.List;

import com.kingming.dao.MsgDao;
import com.kingming.entity.MsgEntity;
import com.kingming.entity.PageBean;

public class MsgBiz {
	MsgDao dao = new MsgDao();
	/**
	 * 查询所有的短信
	 * @param sendto
	 * @return
	 */
	public List<MsgEntity> getMyMsgList(){
		return dao.getMyMsgList();
	}
	
	public PageBean getMyMsgListWithPage(PageBean pageBean){
		return dao.getMyMsgListWithPage(pageBean);
	}
}

四、Control层

package com.kingming.action;

import java.io.IOException;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.kingming.biz.MsgBiz;
import com.kingming.entity.PageBean;

public class MsgAction extends HttpServlet {

	MsgBiz biz = new MsgBiz();
	
	public void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {

		this.doPost(request, response);
	}

	
	public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		
		String page = request.getParameter("p");
		String size = request.getParameter("s");
		PageBean pageBean = new PageBean(page,size);
		pageBean = biz.getMyMsgListWithPage(pageBean);
		
		
		request.setAttribute("PB",pageBean);
		request.getRequestDispatcher("/index.jsp").forward(request, response);
	}
}

五、JSP页面

<%@ page language="java" import="java.util.*" pageEncoding="utf-8" contentType="text/html; charset=utf-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>

<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>

<!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>
    <ul>
    	<c:forEach items="${PB.data }" var="temp"> 
    		<li>${temp.msgid }----${temp.title }</li>
    	</c:forEach>
    </ul>
    <div>
    	<a href="/PageDemo/msg">首页</a>
    	<a href="/PageDemo/msg?p=${PB.prePage}&s=${PB.limitSize}">上一页</a>
    	<a href="/PageDemo/msg?p=${PB.nextPage}&s=${PB.limitSize}">下一页</a>
    	<a href="/PageDemo/msg?p=${PB.countSize}&s=${PB.limitSize}">尾页</a>
    </div>
  </body>
</html>

个人笔记记录一下