package com.javaBean;

import java.sql.*;
import javax.servlet.*;
import javax.servlet.http.*;
import java.math.*;

public class  Pagination{
   private String strPage = null;      //page參數(shù)
   private int curPages;       //page參數(shù)內(nèi)部的值(當(dāng)前頁(yè))
   private int m_rows;       //每頁(yè)顯示的紀(jì)錄數(shù)
   private int pages;      //總頁(yè)數(shù)
   
   public String strPage(HttpServletRequest request, String page){
   try{
       strPage = request.getParameter(page);
      }
      catch(Exception e){
           System.out.println("delcolumn"+e.getMessage());   
      }
      return strPage;
   }
   
   //頁(yè)面數(shù)
   public int curPages(String strPage){
   try{
           if(strPage == null){   //默認(rèn)沒(méi)有就設(shè)置是第一頁(yè)
               curPages = 1;
           }
           else{
               curPages = Integer.parseInt(strPage);     //取得strPage的整數(shù)值
               if(curPages < 1)        //如果小于1,同樣返回是第一頁(yè)
                   curPages = 1;
           }
       }
       catch(Exception e){
           System.out.print("curPages");
       }
       return curPages;
   }
   
   //設(shè)置每頁(yè)要顯示的記錄數(shù)
   public void setRows(int rows){
       m_rows=rows;
   }

   //取得頁(yè)數(shù)
   public int getPages(int rowcounts){
       int test;   //變量
       test=rowcounts%m_rows;  //取得余數(shù)
       if(test==0)
           pages = rowcounts/m_rows;  //每頁(yè)顯示的整數(shù)
           else
           pages=rowcounts/m_rows+1;   //不是的話就加一
	   return pages;
   }
   
   //結(jié)果集的返回
   public ResultSet getPageSet(ResultSet rs,int curPages){
       if(curPages==1){
           return rs;   //如果是就一頁(yè)的話，就返回這個(gè)rs
       }
       else{
           int i=1;
           try{
               while(rs.next()){
                   i=i+1;
                   if(i>((curPages-1)*m_rows))
                       break;  //退出
               }
               return rs;   //從退出開(kāi)始將結(jié)果集返回
           }
           catch(Exception e){
               System.out.print(e.getMessage());
           }
       }
       return rs;
   }
}