pagination.java

简易java框架开源论坛系统源码easyjf_bbs0.1.rar

//***************************************************************
//数据分页的类
//***************************************************************

package conn;

import java.sql.*;
import java.util.*;
import face.*;


public class Pagination 
{
	private ResultSet rs;
	//每页显示的记录数
	private int pageSize;
	//总记录数
	private int count = 0;
	//总页数
	private int pageCount;
	//结果集的MetaData
	private ResultSetMetaData rsmd = null;
	//总列数
	private int fieldCount = 0;

	public Pagination()
	{
	}
	public Pagination(FlashDbDao fdb) throws Exception
	{
		this.rs = fdb.getRs();
	}
	public void setPageSize(int pageSize)
	{
		this.pageSize = pageSize;
	}
	//-------------------------------------------------------------------------
	//传递一个ResultSet对象
	//-------------------------------------------------------------------------
	public void setRs(ResultSet rs)
	{
		this.rs = rs;
	}
	//-------------------------------------------------------------------------
	//获取一个ResultSetMetaData
	//-------------------------------------------------------------------------
	public ResultSetMetaData getRsmd()throws Exception
	{
		if (rsmd == null)
		{
			this.rsmd = rs.getMetaData();
		}
		return rsmd;
	}
	//-------------------------------------------------------------------------
	//返回ResultSet的总列数
	//-------------------------------------------------------------------------
	public int getFiledCount()throws Exception
	{
		return getRsmd().getColumnCount();
	}
	//-------------------------------------------------------------------------
	//返回总记录数
	//-------------------------------------------------------------------------
	public int getCount()throws Exception
	{
		this.count = 0;
		rs.beforeFirst();
		while(rs.next())
		{
			this.count++;
		}
		return this.count;
	}
	//-------------------------------------------------------------------------
	//返回当前页的记录数
	//-------------------------------------------------------------------------
	public int getNonce(int pageNo) throws Exception
	{
		rs.beforeFirst();
		int counter = 0;
		while(rs.next() && counter < (pageNo - 1) * pageSize - 1 )counter++;
		counter = 0;
		while (rs.next() && counter < pageSize)counter++;
		return counter;
	}
	//-------------------------------------------------------------------------
	//返回产生的页数
	//-------------------------------------------------------------------------
	public int getPageCount()throws Exception
	{
		return getCount()%pageSize ==0 ? getCount()/pageSize : getCount()/pageSize + 1;
	}
	//-------------------------------------------------------------------------
	//得到指定页的记录集
	//-------------------------------------------------------------------------
	public List getPageResult(int pageNo,ResultBean rb)throws Exception
	{
		rs.beforeFirst();
		int counter = 0;
		while(rs.next() && counter < (pageNo - 1) * pageSize - 1 )counter++;
		List rl = new ArrayList();
		ResultSetMetaData rsmd = rs.getMetaData();
		counter = 0;
		rs.previous();
		while(rs.next() && counter < pageSize)
		{
			String temp = "";
			for(int i = 0; i< rb.getAmount(); i++)
			{
				temp += String.valueOf(rs.getObject(i + 1)) + "#";
			}
			ResultBean newRb = rb.getResultBean();
			newRb.setProperty(temp);
			rl.add(newRb);
			counter++;
		}
		return rl;
	}
}