roomdata.java

java与mdb,一个简单的java访问数据库系统

import java.sql.*;

public class RoomData 
{
	private Statement stmt=null;
	ResultSet rs=null;
	private Connection con=null;
	String sql;
	String strUrl="jdbc:odbc:CRRS";
  
	public RoomData()
	{
	}
	//打开数据连接
	public void OpenConn() throws Exception
	{
		try 
		{
			Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
			con=DriverManager.getConnection(strUrl);
		}
		catch(Exception e)
		{
			System.out.println("OpenCon : "+e.getMessage());
		}
	}
	
	//从数据库中选择会议室信息，并返回RoomList对象
	public RoomList selectRoomList(String sql)
	{
		Room rm;
		RoomList rml=new RoomList();
		stmt=null;
		rs=null;
		try
		{
			stmt=con.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,ResultSet.CONCUR_READ_ONLY);
			rs=stmt.executeQuery(sql);
			while(rs.next())
			{
				String room=rs.getString("rm_Sn");
				int capacity=rs.getInt("rm_SeatingCapacity");
				
				//将数据库中相应的字段集合起来赋给Room对象
				rm=new Room(room,capacity);
				//在RoomList对象列表中添加一个Room对象
				rml.getRm().add(rm);
			}
		}
		catch(SQLException e)
		{
			System.err.println("executeSelect : "+e.getMessage());
		}
		return rml;
	}

	public void closeStmt()
	{
		try
		{
			stmt.close();
		}
		catch (SQLException e)
		{
			System.out.println("closeStmt:"+e.getMessage());
		}

	}
	//关闭数据连接
	public void closeConn()
	{
		try 
		{
			con.close();
		}
		catch(SQLException ex)
		{
			System.err.println("aq.closeCon : "+ex.getMessage());
		}
	}
	public static String toGBK(String str)
	{
		try
		{
			if(str==null)   
			str="";
			else
			str=new String(str.getBytes("ISO-8859-1"),"GBK");  
		}
		catch(Exception e)
		{
			System.out.println(e);
		}
		return str;
	}
}