页面分页函数

 

package  com.vitamin.download;
import  javax.servlet. * ;
import  javax.servlet.http. * ;
import  java.math. * ;
import  java.sql. * ;

public   class  Pagination 
{
    
     private  String strPage  =   null ;
     private   int  curPage; // 当前页；
     private   int  m_rows; // 每页包括的几个数据项;
     private   int  totalPage; // 总页数
    
     public  Pagination()
     {
        
    }
    
     public   int  getRows()
     {
         return   this .m_rows;
    }
    
     public  Pagination( int  rows)
     {
         this .setRows(rows);
    }
    
     public  String getstrPage(HttpServletRequest request,String page)
     {
         try
         {
                strPage  =  request.getParameter(page);
        }
         catch (Exception e)
         {
                System.out.print(e.getMessage());
        }
         return  strPage;
    }
    
     public   int  getcurPage(String strPage)
     {
         try
         {
             if (strPage == null )
             {
                 this .curPage  = 1 ;
            }
             else
             {
                 this .curPage  =  Integer.parseInt(strPage);
                 if ( this .curPage < 1 )
                 {
                     this .curPage  = 1 ;
                }
            }
            
        }
         catch (Exception e)
         {
            System.out.print( " curPages " );
        }
         return   this .curPage;
    }
    
      public   void  setRows( int  rows)
      {
           m_rows = rows;
     }
        //  取得页数
      
      public   int  getTotalPages( int  rowcounts)
      {
            int  test; //  变量
           test = rowcounts % m_rows; //  取得余数
            if (test == 0 )
            {
               totalPage  =  rowcounts / m_rows; //  可以整除，总页数；
           }
            else
            {
               totalPage = rowcounts / m_rows + 1 ; //  不是的话就加一  
           }
            return  totalPage; //  返回页数
      }
        //  结果集的返回
       
      public  ResultSet getPageSet(ResultSet rs, int  curPages)
      {
            if (curPages == 1 )
            {
              
                return  rs; //  如果就只有一页
           }
            else
            {
                int  i = 1 ;
                try
                {
                    while (rs.next()) // 使rs跳到(curPages-1)*m_rows 那行；
                    {
                       i = i + 1 ;
                        if (i > ((curPages - 1 ) * m_rows))
                        {
                            break ; //  退出
                       }
                   }
                    return  rs; //  从退出开始将结果集返回
               }
                catch (Exception e)
                {
                   System.out.print(e.getMessage());
               }
           }
            return  rs;
       }


}