传统servelt项目之分页操作

package com.briup.common.util;

import java.util.List;

/**
 * 分页的三个基本属性
 * 1.每页几条记录size  可以有默认值5
 * 2.当前页号  index    可以有默认值1
 * 3.记录总数totalCount：不可能有默认值，需要查询数据库获取真正的记录总数
 * 
 * 4.一共多少页 ：totalPageCount=totalCount/size+1
 *         5  30  31 32 33 34 35  
 * 5.上一页    index-1  当前页1，上一页1
 * 6.下一页   index+1  当前页是最后一页  下一页：还是最后一页
 * 
 * 扩展
 * 分页Bean还可以放要查询的数据  protected List<T> list;
 * 分页Bean还可以放页码列表     [1]  2  3  4  5   private int[] numbers;
 * 
 * @author Administrator
 *
 * @param <T>
 */
public class PageBean<T> {
    private int size = 5;//每页显示记录  //
    private int index = 1;// 当前页号      
    private int totalCount = 0;// 记录总数      ok
    
    private int totalPageCount = 1;// 总页数   ok
    
    
    
    private int[] numbers;//展示页数集合  //ok
    protected List<T> list;//要显示到页面的数据集  

    /**
     * 得到开始记录
     * @return
     */
    public int getStartRow() {

        return (index - 1) * size;
    }

    /**
     * 得到结束记录
     * @return
     */
    public int getEndRow() {
        
        return index * size;
    }

    /**
     * @return Returns the size.
     */
    public int getSize() {        
        return size;
    }

    /**
     * @param size
     * The size to set.
     */
    public void setSize(int size) {
        if (size > 0) {
            this.size = size;
        }
    }
    /**
     * @return Returns the currentPageNo.
     */
    public int getIndex() {
        if (totalPageCount == 0) {
            
            return 0;
        }
        
        return index;
    }

    /**
     * @param currentPageNo
     * The currentPageNo to set.
     */
    public void setIndex(int index) {
        if (index > 0) {
            this.index = index;
        }
    }

    /**
     * @return Returns the totalCount.
     */
    public int getTotalCount() {
        return totalCount;
    }

    /**
     * @param totalCount
     *  The totalCount to set.
     */
    public void setTotalCount(int totalCount) {
        if (totalCount >= 0) {
            this.totalCount = totalCount;
            setTotalPageCountByRs();//根据总记录数计算总页??
        }
    }

    
    public int getTotalPageCount() {
        return this.totalPageCount;
    }

    /**
     * 根据总记录数计算总页??
     * 5   
     * 20    4
     * 23    5
     */
    private void setTotalPageCountByRs() {
        if (this.size > 0 && this.totalCount > 0 && this.totalCount % this.size == 0) {
            this.totalPageCount = this.totalCount / this.size;
        } else if (this.size > 0 && this.totalCount > 0 && this.totalCount % this.size > 0) {
            this.totalPageCount = (this.totalCount / this.size) + 1;
        } else {
            this.totalPageCount = 0;
        }
        setNumbers(totalPageCount);//获取展示页数集合
    }

    public int[] getNumbers() {
        return numbers;
    }
    
    /**
     * 设置显示页数集合
     * 
     * 默认显示10个页码
     * 41  42  43  44    [45 ]   46  47  48  49  50
     * 
     * 
     *  [1] 2  3 4  5 6 7 8  9  10
     *  
     *  41  42  43  44    45    46  47  [48]  49  50
     * @param totalPageCount
     */
    public void setNumbers(int totalPageCount) {
        if(totalPageCount>0){
            //!.当前数组的长度
            int[] numbers = new int[totalPageCount>10?10:totalPageCount];//页面要显示的页数集合
            int k =0;
            //
            //1.数组长度<10   1 2 3 4 ....   7
            //2.数组长度>=10
            //     当前页<=6  1 2 3 4    10
            //     当前页>=总页数-5           ......12 13 14 15  
            //     其他                                5  6  7 8   9 当前页(10)  10  11 12  13
            for(int i = 0;i < totalPageCount;i++){
                //保证当前页为集合的中??
                if((i>=index- (numbers.length/2+1) || i >= totalPageCount-numbers.length) && k<numbers.length){
                    numbers[k] = i+1;
                    k++;
                }else if(k>=numbers.length){
                    break;
                }                
            }
            
            this.numbers = numbers;
        }
        
    }
    
    public void setNumbers(int[] numbers) {
        this.numbers = numbers;
    }

    public List<T> getList() {
        return list;
    }

    public void setList(List<T> list) {
        this.list = list;
    }


/*
    public static int getTotalPageCount(int iTotalRecordCount, int iPageSize) {
        if (iPageSize == 0) {
            return 0;
        } else {
            return (iTotalRecordCount % iPageSize) == 0 ? (iTotalRecordCount / iPageSize) : (iTotalRecordCount / iPageSize) + 1;
        }
    }*/
}

package com.briup.bean;

import java.io.Serializable;

public class Customer implements Serializable{
    private static final long serialVersionUID = -1415977267636644567L;
    private Long id;
    private String name;
    private String password;
    private String zip;
    private String address;
    private String telephone;
    private String email;
    public Customer() {
    }
    public Customer(Long id, String name, String password, String zip,
            String address, String telephone, String email) {
        super();
        this.id = id;
        this.name = name;
        this.password = password;
        this.zip = zip;
        this.address = address;
        this.telephone = telephone;
        this.email = email;
    }
    public Customer(String name, String password, String zip,
            String address, String telephone, String email) {
        super();
        
        this.name = name;
        this.password = password;
        this.zip = zip;
        this.address = address;
        this.telephone = telephone;
        this.email = email;
    }
    public Long getId() {
        return id;
    }
    public void setId(Long id) {
        this.id = id;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getPassword() {
        return password;
    }
    public void setPassword(String password) {
        this.password = password;
    }
    public String getZip() {
        return zip;
    }
    public void setZip(String zip) {
        this.zip = zip;
    }
    public String getAddress() {
        return address;
    }
    public void setAddress(String address) {
        this.address = address;
    }
    public String getTelephone() {
        return telephone;
    }
    public void setTelephone(String telephone) {
        this.telephone = telephone;
    }
    public String getEmail() {
        return email;
    }
    public void setEmail(String email) {
        this.email = email;
    }
}

package com.briup.dao;

import java.util.List;

import com.briup.bean.Customer;
import com.briup.bean.Student;

public interface StudentDao {
    /**
     * ??????????
     * @return
     */
    public List<Customer> findAll();
    /**
     * ????????Χ?????
     * @param start
     * @param end
     * @return
     */
    public List<Customer> findStu(int start, int size);
    /**
     * ?????¼????
     * @return
     */
    public int findCount();
    /**
     * ???????????????¼????
     * @param name
     * @param minScore
     * @return
     */
    public int findCount(String name);
    /**
     * ????????????????????????
     * @param start
     * @param end
     * @param name
     * @param minScore
     * @return
     */
    public List<Customer> findStu(int start, int size, String name);
            
    
}

package com.briup.dao.impl;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.List;

import com.briup.bean.Customer;
import com.briup.bean.Student;
import com.briup.common.util.DBUtil;
import com.briup.dao.StudentDao;

public class StudentDaoImpl   implements StudentDao {
    public List<Customer> findAll() {
        Connection conn =DBUtil.getConnection();
        Statement stmt =null;
        ResultSet rs =null;
        List<Customer> stuList = new ArrayList<Customer>();
        try {
            stmt =conn.createStatement();
            rs = stmt.executeQuery("select * from student");
            while(rs.next()){
                Customer cus1 = new Customer();
                cus1.setId(rs.getLong("customer_id"));
                cus1.setAddress(rs.getString("address"));
                cus1.setEmail(rs.getString("email"));
                cus1.setName(rs.getString("name"));
                cus1.setPassword(rs.getString("password"));
                cus1.setTelephone(rs.getString("telephone"));
                cus1.setZip(rs.getString("zip"));
                stuList.add(cus1);
            }
            
        } catch (SQLException e) {
            e.printStackTrace();
        }finally{
            DBUtil.closeAll(rs, stmt, conn);
        }
        return stuList;
    }

    public List<Customer> findStu(int start, int size) {
        Connection conn =DBUtil.getConnection();
        PreparedStatement pstmt =null;
        ResultSet rs =null;
        List <Customer> stuList = new ArrayList<Customer>();
        try {
            String sql = "select * from  tbl_customer limit ?,?";
            pstmt =conn.prepareStatement(sql);
             pstmt.setInt(1, start);
             pstmt.setInt(2, size);
            rs = pstmt.executeQuery();
            
        
            while(rs.next()){
                /*private Long id;
                private String name;
                private String password;
                private String zip;
                private String address;
                private String telephone;
                private String email;*/
                Customer cus1 = new Customer();
                cus1.setId(rs.getLong("customer_id"));
                cus1.setAddress(rs.getString("address"));
                cus1.setEmail(rs.getString("email"));
                cus1.setName(rs.getString("name"));
                cus1.setPassword(rs.getString("password"));
                cus1.setTelephone(rs.getString("telephone"));
                cus1.setZip(rs.getString("zip"));
                
                stuList.add(cus1);
            }
            
        } catch (SQLException e) {
            e.printStackTrace();
        }finally{
            DBUtil.closeAll(rs, pstmt, conn);
        }
        return stuList;
    }

    public int findCount() {
        Connection conn =DBUtil.getConnection();
        Statement stmt =null;
        ResultSet rs =null;
        List <Student> stuList = new ArrayList<Student>();
        int count = 0;
        try {
            stmt =conn.createStatement();
            rs = stmt.executeQuery("select count(*) from tbl_customer");
            rs.next();
            count = rs.getInt(1);            
        } catch (SQLException e) {
            e.printStackTrace();
        }finally{
            DBUtil.closeAll(rs, stmt, conn);
        }
        
        return count;
    }

    public int findCount(String name) {
        Connection conn =DBUtil.getConnection();
        Statement stmt =null;
        
        ResultSet rs =null;
        List <Student> stuList = new ArrayList<Student>();
        int count = 0;
        try {
            StringBuilder sql = new StringBuilder("select count(*) from tbl_customer where 1=1 ");
            if(name != null && !"".equals(name)){
                sql.append(" and name like ‘%"+name+"%‘");
            }
            
            stmt =conn.createStatement();
            rs = stmt.executeQuery(sql.toString());
            rs.next();
            count = rs.getInt(1);    
            System.out.println("StudentDaoImpl.findCount()"+count);
        } catch (SQLException e) {
            e.printStackTrace();
        }finally{
            DBUtil.closeAll(rs, stmt, conn);
        }
    
        return count;
    }


    public List<Customer> findStu(int start, int size, String name
            ) {
        Connection conn =DBUtil.getConnection();
        Statement stmt =null;
        ResultSet rs =null;
        PreparedStatement pstmt=null;
        List<Customer> stuList = new ArrayList<Customer>();
        try {
            stmt =conn.createStatement();
            StringBuilder sql = new StringBuilder("select  * from tbl_customer cus where 1=1 ");
            if(name != null && !"".equals(name)){
                sql.append(" and name like ‘%"+name+"%‘");
            }
            
            sql.append(" order by score desc");
            
            String sql2 = "select * from  tbl_customer limit ?,?";
            
              pstmt = conn.prepareStatement(sql2);
              pstmt.setInt(1, start);
              pstmt.setInt(2, size);
            rs = pstmt.executeQuery();
            while(rs.next()){
                Customer cus1 = new Customer();
                cus1.setId(rs.getLong("customer_id"));
                cus1.setAddress(rs.getString("address"));
                cus1.setEmail(rs.getString("email"));
                cus1.setName(rs.getString("name"));
                cus1.setPassword(rs.getString("password"));
                cus1.setTelephone(rs.getString("telephone"));
                cus1.setZip(rs.getString("zip"));
                stuList.add(cus1);
            }
            
        } catch (SQLException e) {
            e.printStackTrace();
        }finally{
            DBUtil.closeAll(rs, stmt, conn);
        }
        return stuList;
    }
}

package com.briup.service;

import java.util.List;

import com.briup.bean.Customer;
import com.briup.bean.Student;
import com.briup.common.util.PageBean;

public interface StudentService {

    /**
     * ??????????
     * @return
     */
    public List<Customer> findAll();
    /**
     * ?????????????????????????
     * @param pageBean
     */
    public void findStu(PageBean<Customer> pageBean);
    /**
     * ?????????????????????
     * @param pageBean
     */
    public void findStu(PageBean<Customer> pageBean, String name);
    

}

package com.briup.service.impl;

import java.util.List;

import com.briup.bean.Customer;
import com.briup.bean.Student;
import com.briup.common.util.PageBean;
import com.briup.dao.StudentDao;
import com.briup.dao.impl.StudentDaoImpl;
import com.briup.service.StudentService;

public class StudentServiceImpl implements StudentService {

    private StudentDao stuDao = new StudentDaoImpl();    

    public List<Customer> findAll() {        
        return this.stuDao.findAll();
    }

    public void findStu(PageBean<Customer> pageBean) {
        //????????????¼????
        //int totalCount = this.stuDao.findAll().size();//????
        int totalCount = this.stuDao.findCount();
        System.out.println("count="+totalCount);
        //??ü?¼???????PageBean?е?????????(totalCount,totalPageCount,numbers)?????list????
        pageBean.setTotalCount(totalCount);
        
        
        //????DAO???????????????????????pageBean??list????
        /*
         *ÿ?size = 5????¼ 
         *  ????    ?????¼??>=    ?????¼??<=    <
         *  1      0            4             5
         *  2      5           9             10
         *  3      10           14            15
         *  
         *  index    (index-1)*size                          index*size
         *  
         */
        //int start = (pageBean.getIndex()-1)*pageBean.getSize();
        //int end=  pageBean.getIndex()*pageBean.getSize();
        int start = pageBean.getStartRow();
        int end = pageBean.getEndRow();
        int size = pageBean.getSize();
        List<Customer> list = this.stuDao.findStu(start,size);
        pageBean.setList(list);
        
    }

    public void findStu(PageBean<Customer> pageBean, String name) {
        //??????????????????????¼????
        int totalCount = this.stuDao.findCount(name);
        System.out.println("count="+totalCount);
        
        //??ü?¼???????PageBean?е?????????(totalCount,totalPageCount,numbers)?????list????
        pageBean.setTotalCount(totalCount);
        
        
        //????DAO???????????????????????pageBean??list????                
        int start = pageBean.getStartRow();
        int end = pageBean.getEndRow();
        int size = pageBean.getSize();
        List<Customer> list = this.stuDao.findStu(start,size,name);
        pageBean.setList(list);
        
    }

}

package com.briup.web.servlet;

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.briup.bean.Customer;
import com.briup.common.util.PageBean;
import com.briup.service.StudentService;
import com.briup.service.impl.StudentServiceImpl;

public class ShowAllServlet extends HttpServlet {

    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        request.setCharacterEncoding("utf-8");
        
        String sindex = request.getParameter("index"); // null ""
        int index = 1;
        System.out.println(index);
        try {
            index = Integer.parseInt(sindex);//"5"
        } catch (NumberFormatException e) {
            e.printStackTrace();
        }
        
        String ssize = request.getParameter("size"); // null ""
        int size = 5;
        try {
            size = Integer.parseInt(ssize);//"5"
        } catch (NumberFormatException e) {
            e.printStackTrace();
        }
        
        String name = request.getParameter("name");
        
        
        // 2
        PageBean<Customer> pageBean = new PageBean<Customer>();
        pageBean.setIndex(index);
        pageBean.setSize(size);
        StudentService stuService = new StudentServiceImpl();
        //List<Student> stuList = stuBiz.findAll();
        //stuService.findStu(pageBean);//?????????stuList??????????????????е???????PageBean??
        stuService.findStu(pageBean,name);
        request.setAttribute("pageBean", pageBean);// !!!!!!!
        request.setAttribute("name", name);
        
        // 3com.bjsxt

        request.getRequestDispatcher("/jsp/showAll.jsp").forward(request,
                response);
    }

    public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        this.doGet(request, response);
    }

}

<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%@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>
    <base href="<%=basePath%>">
    
    <title>查询并显示所有学生信息</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">
    -->
    <script type="text/javascript">
        function changeIndex(index){
             location.href="stu?index="+index;
        }
        
        function changeSize(size){
            //alert(size);
            location.href= "stu?size="+size;
        }
        
        function change2(index,size){
             //location.href="servlet/ShowAllServlet?index="+index+"&size="+size;
             document.forms[0].action="stu?index="+index+"&size="+size;
             document.forms[0].submit();
        }
        
        function change(index,size){
            document.forms[0].index.value = index;
            //document.forms[0].size.value = size;
            document.getElementById("size").value = size;
             document.forms[0].submit();
        }
        
        
    </script>
  </head>
  
  <body> 
      <hr>
       <form action="stu" method="post" id="form1">
           <table align="center">
               <tr>
                   <td>姓名</td>    
                   <td>                   
                       <input type="text" name="name" value="${name }">
                       <input type="hidden"  name="index" value="">
                       <input type="hidden" id="size" name="size">
                   </td>
                   
                   <td><input type="submit" value="提交"></td>
               </tr>
           </table>
       </form>       
       <hr>       
  
    <!-- 显示所有学生   /stumanager/    -->
    <table align="center" border="1" width="60%">
        <tr>
            <th>学生 编号</th>
            <th>学生姓名</th>
            <th>学生年龄</th>
            <th>学生成绩</th>
            <th>vs.index</th>
            <th>更新操作</th>
            <th>删除操作</th>
        </tr>
        <c:forEach items="${pageBean.list}" var="stu" varStatus="vs">
            <tr>
    
                <td>${stu.id }</td>
                <td>${stu.name }</td>
                <td>${stu.password}</td>
                <td>${stu.zip }</td>
                <td>${stu.address }</td>
                <td>${stu.telephone }</td>
                <td>${stu.email }</td>
                <td>${vs.index }</td>
                <td><a href="/stumanager/servlet/StudentServlet?operate=preupdate&sid=${stu.id}">更新</a></td>
                <td><a href="/stumanager/servlet/StudentServlet?operate=delete&sid=${stu.id}">删除</a></td>
            </tr>
        </c:forEach>
        <tr>
            <td colspan="11" align="center">
                 <a href="javascript:change(1,${pageBean.size })">首页</a> 
                <c:if test="${pageBean.index !=1 }">
                    <a href="javascript:change(${pageBean.index-1 },${pageBean.size })">上一页  </a>
                </c:if>
                <c:if test="${pageBean.index ==1 }">
                    上一页 
                </c:if>
                <c:forEach items="${pageBean.numbers }" var="num">
                    <c:if test="${num ==pageBean.index }"> 
                        [<a href="javascript:change(${num },${pageBean.size })">${num }</a>]
                    </c:if>
                    <c:if test="${num != pageBean.index }">
                        <a href="javascript:change(${num },${pageBean.size })">${num }</a>
                    </c:if>
                </c:forEach>
                <c:if test="${pageBean.index != pageBean.totalPageCount }">
                    <a href="javascript:change(${pageBean.index+1 },${pageBean.size })">下一页</a>
                </c:if>
                <c:if test="${pageBean.index == pageBean.totalPageCount }">
                    下一页 
                </c:if>             
                 <a href="javascript:change(${pageBean.totalPageCount },${pageBean.size })">末页</a> 
                每页
                    <select onchange="change(${pageBean.index},this.value)">
                        <c:forEach begin="5" end="25" step="5" var="i">
                            <c:if test="${i==pageBean.size }">
                                <option value="${i }" selected="selected">${i }</option>
                            </c:if>
                            <c:if test="${i!=pageBean.size }">
                                <option value="${i }">${i }</option>
                            </c:if>
                        </c:forEach>
                    </select>
                条记录
                 直接跳到第 
                <select onchange="change(this.value,${pageBean.size})">
                    <c:forEach  begin="1"  end="${ pageBean.totalPageCount }" var="num">
                        <c:if test="${num == pageBean.index }">  
                            <option value="${num }" selected="selected">${num }</option>
                        </c:if>
                        <c:if test="${num != pageBean.index }">
                            <option value="${num }">${num }</option>
                        </c:if>
                    </c:forEach>
                </select> 
                  页 
                                   
                  共${pageBean.totalCount }条记录
            </td>            
        </tr>
    </table>
   
  </body>
</html>