servlet分頁

採用servlet進行分頁處理

Java代碼

步驟：   

1.  創建SepPage類，並設置有關的方法。   

2.  在進行頁面的轉移時傳遞並當前的頁面並傳遞參數。   

3.  進行分頁處理。   

a.  計算總記錄數   

b.  怎麼樣進行分頁   

c.  首頁顯示處理   

d.  傳遞有關參數   

e.  獲取有關傳遞的頁面的參數   

 

  

實例：以查詢所有的用戶信息爲例子進行說明   

  

package bean;
/**********************分頁類描述************************/
public class SepPage
{
    private int allRows; // 一共有多少行記錄
    private int curPage = 1; // 當前頁面
    private int rowPerPage = 8; // 一頁顯示多少行
    private int allPages; // 一共有多少頁
    public int getAllRows()
    {
        return allRows;
    }
    public void setAllRows(int allRows)
    {
        this.allRows = allRows;
    }
    public int getCurPage()
    {
        return curPage;
    }
    public void setCurPage(int curPage)
    {
        this.curPage = curPage;
    }
    public int getRowPerPage()
    {
        return rowPerPage;
    }
    public void setRowPerPage(int rowPerPage)
    {
        this.rowPerPage = rowPerPage;
    }
    public int getAllPages()
    {
        return allPages;
    }
    public void setAllPages(int allPages)
    {
        this.allPages = allPages;
    }
}


2.數據接收servlet
package servlet;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import bean.DBOperationBean;
import java.util.*;
import util.Convert;
import java.sql.*;
import bean.*;
/**
 * servlet類，獲取有關客戶的信息並進行相關的處理
 * @author qihuasun
 */
public class CustomerServlet extends HttpServlet
{
    //查詢所有sql語句
    public static final String SELECTBYALL="select * from SCOTT.EXRM_T_CUSTOMER order by CUM_FULLNAME ";
    public void doGet(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException
    {
         this.doPost(request, response);
     }
    public void doPost(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException
    {
        //處理有關中文亂碼問題
        request.setCharacterEncoding("GBK");
        response.setContentType("text/html;charset=GBK");
        response.setCharacterEncoding("GBK");
        String status=request.getParameter("status").trim();//獲取頁面傳遞的標誌位status
        String path="error.jsp";
         if(!status.equals("")|| status!=null)
         {

           if(status.equals("findall"))
          {
               DBOperationBean db=new DBOperationBean();
              String page=request.getParameter("curpage");
               try
                {
                   int curPage = Integer.parseInt(request.getParameter("curPage"));
//獲取頁面傳遞的參數
                    SepPage pa=new SepPage();
                    pa.setCurPage(curPage);
                    ArrayList al=db.query(this.SELECTBYALL,pa);
                    if(al!=null)
                     {
                        // path="main.jsp";
                          path="TestMain2.jsp";
                          request.setAttribute("all",al);
                     }
                    else
                    {
                        path="error.jsp";
                    }

                }
                catch(Exception ex)
                {
                    ex.printStackTrace();
                }
          }

         }
         request.getRequestDispatcher(path).forward(request,response);

    }

}

4.  數據訪問類
 package bean;
import java.sql.*;

import javax.sql.*;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.naming.*;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;
import java.util.*;
import bean.SepPage;
/**
 * bean類，獲取有關配置文件的信息的頁面的信息，並進行有關的處理
 * @author qihuasun
 */
public class DBOperationBean
{
     //驅動
   private final String DBDRIVER    = "oracle.jdbc.driver.OracleDriver";
   // 數據庫連接地址
   private final String DBURL       = "jdbc:oracle:thin:@127.0.0.1:1521:data";
    // 數據庫用戶名
   private final String DBUSER      = "SCOTT";
    // 數據庫連接密碼
   private final String DBPASSWORD  = "sqh";
    // 聲明一個數據庫連接對象
   private Connection conn              = null ;
   private PreparedStatement  pstm=null;
   private ResultSet rs=null;
   public DBOperationBean()
   {
       this.init();
   }
    private void init()  //從數據庫連接屬性XML配置文件中獲取關於連接的信息
    {
        conn=new DBConnection().getConnection();
    }
    private Connection getConnection() //取得數據庫連接並設置爲當前連接
    {
         try
         {
              Class.forName(DBDRIVER);

              conn = DriverManager.getConnection(DBURL,DBUSER,DBPASSWORD);// 連接數據庫
              System.out.println("connected");
         }
         catch(Exception ex)
         {
             ex.printStackTrace();
         }


        return this.conn;
    }

    public ArrayList query(String sql,SepPage page) throws Exception
    {//執行查詢，返回結果集
        ArrayList al=new ArrayList();
        try
        {
            Connection conn=this.getConnection();
            pstm = conn.prepareStatement(sql, ResultSet.TYPE_SCROLL_INSENSITIVE,
                    ResultSet.CONCUR_READ_ONLY);
            rs=pstm.executeQuery();
            rs.last(); // 移動到最後一行
            page.setAllRows(rs.getRow()); // 設置一共有多少行記錄
            // 算出有多少頁
            if (page.getAllRows() % page.getRowPerPage()== 0)
            {
                page.setAllPages(page.getAllRows() / page.getRowPerPage());
            }
            else
            {
                page.setAllPages(page.getAllRows() / page.getRowPerPage() + 1);
            }
            //判定是否是第一頁
            if (page.getCurPage() == 1) //當前頁
            {
                // 將指針移動到此ResultSet對象的開頭,正好位於第一行之前
                rs.beforeFirst();
            }
            else
            {
                // 將指針移動到此ResultSet對象的給定行編號
                rs.absolute((page.getCurPage() - 1) * page.getRowPerPage());
            }
            int i = 0;
            while(rs.next() && i < page.getRowPerPage())
            {
                 Customer cu=new Customer();
                 cu.setId(rs.getInt("CUM_ID"));
                 cu.setName(rs.getString("CUM_FULLNAME"));
                 cu.setAddress(rs.getString("CUM_MAINADDRESS"));
                 cu.setPhone(rs.getString("CUM_PHONE"));
                 al.add(cu);
                 i++;
            }
        }
        catch(Exception ex)
        {
             ex.printStackTrace();
        }
        finally
        {
               try
               {
                   if(conn!=null)
                   {
                       this.conn.close();
                   }
               }
               catch(Exception ex)
               {
                   ex.printStackTrace();
               }
        }
        return al;
    }
}

4、頁面顯示
  <%@ page language="java" contentType="text/html;charset=GBK"%>
<%@ page import="java.util.*,bean.SepPage"%>
<%@page import="bean.Customer;"%>

<%
    ArrayList all = (ArrayList) request.getAttribute("all");
    SepPage seppage = (SepPage) request.getAttribute("pagebean");
//獲取設置的SepPage參數
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3c.org/TR/1999/REC-html401-19991224/loose.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
    <head>
        <title>客戶管理</title>
        <link href="css/style.css" rel="stylesheet" />
    </head>
    <body>
        <div class="top" >
            『 作者管理 』
        </div>
        <div class="center">
            <form action="AuthorServlet?status=selectbylike&curPage=1" method="post" style="margin: 0;">
                <table class="fine" cellpadding="0" cellspacing="0">
                    <tr>
                        <td colspan="3" style="height: 40px;">

                        </td>
                    </tr>
                    <tr>
                       <td>
                              序號
                        </td>
                        <td>
                            客戶名稱
                        </td>
                        <td>
                            聯繫電話
                        </td>
                            <td>
                            地址
                        </td>
                        &nbsp;&nbsp;&nbsp;&nbsp;<td>
                            操作
                        </td>
                    </tr>
                    <%
                        int i=0;
                        if (all != null && all.size() != 0)
                         {
                            for (int j=0;j<all.size();j++)
                            {
                                i++;
                                Customer cus=(Customer)all.get(j);
                                int authorId1=cus.getId();
                                String str="找不到記錄！！！";
                                if(i==0)
                                {


                                   out.println("<scrtipt>alert('找不到記錄')<script>");
                                }
                                else
                                {%>

                        <tr>
                        <td>

                            <%=i%>
                        </td>
                        <td>

                            <%=cus.getName()%>
                        </td>
                        <td>
                            <%=cus.getPhone()%>
                        </td>
                            <td>
                            <%=cus.getAddress()%>
                        </td>
                        <td>
             <td><a href="CustomerServlet?status=selectbyid&id=<%=cus.getId()%>">更新</a>&nbsp;&nbsp;&nbsp;&nbsp;</td>&nbsp;&nbsp;

            <td><a href="CustomerServlet?status=delete&id=<%=cus.getId()%>" οnclick="if(confirm('是否刪除業務信息?')){return   true;}else{return   false;}">刪除</a>&nbsp;&nbsp;&nbsp;&nbsp;</td>
            <td><a href="addCus.jsp">添加</a></td>
                    </tr>

                               <%}%>

                    <%
                        }//end for循環
                    }//end if all != null
                    %>
                    <%
                        if (seppage != null) {
                    %>
                    <tr>
                        <td colspan="3"
                            style="height: 32px; text-align: right; font-weight: bold; padding-right: 10px;">
                            <font color="#FF5BAD">一共有&nbsp;<font color="red"><%=seppage.getAllPages()%></font>&nbsp;頁&nbsp;&nbsp;當前在第&nbsp;<font
                                color="red"><%=seppage.getCurPage()%></font>&nbsp;頁&nbsp;&nbsp;&nbsp;&nbsp;</font>
                            <%
                                if (seppage.getCurPage() != 1) //不是第一頁，則首頁，上一頁可用
                                {
                            %>
                            <a href="CustomerServlet?status=selectbyall&curPage=1">首 頁</a>&nbsp;&nbsp;
                            <a
                                href="CustomerServlet?status=selectbyall&curPage=<%=seppage.getCurPage()-1 %>">上一頁</a>
                            <%
                                }
                            %>
                            &nbsp;&nbsp;
                            <%
                                if (seppage.getCurPage() != seppage.getAllPages())//不是最後一頁，則有下一頁和末頁
                                 {
                            %>
                            <a
                                href="CustomerServlet?status=selectbyall&curPage=<%=seppage.getCurPage()+1 %>">下一頁</a>&nbsp;&nbsp;
                            <a
                                href="CustomerServlet?status=selectbyall&curPage=<%=seppage.getAllPages() %>">末
                                頁</a>
                            <%
                                }
                            %>

                        </td>
                    </tr>
                    <%
                        }
                    %>
                    </table>
                    </form>
<form action="CustomerServlet?status=selectbylike&curPage=1" method="post" style="margin: 0;">
                <table class="fine" cellpadding="0" cellspacing="0">
                    <tr>
                        <td colspan="3" style="height: 40px;">
                            <select style="height: 20px" name="sel">
                                <option selected value="由客戶姓名">
                                    由客戶姓名
                                </option>
                                <option value="由地址">
                                    由地址
                                </option>
                            </select>
                            &nbsp;&nbsp;
                            <input  type="text" name="in" style="width: 200px" /><input  type="submit" value="查 找" />
                        </td>
                    </tr>
                    </table>
                    </form>
    </div>
    </body>