db_type.java

精通Jsp-Web开发技术与典型应用 源码

package ch18.JavaBean;
import java.sql.ResultSet;
import java.sql.SQLException;

import ch18.JavaBean.DB_Conn;
import ch18.JavaBean.Type;
public class DB_type
{
	DB_Conn db_conn=new DB_Conn();
	//根据商品的类别编号查询出此商品所属的类别名称
	public String getTypename(int typeid)
	{
		db_conn.ConnectDB();
		ResultSet rs=null;
		try
		{
			String sql="select * from type where typeid="+typeid;
			sql = new String(sql.getBytes("ISO8859-1"), "GB2312");
			rs=db_conn.sm.executeQuery(sql);
			Type type=null;
			String typename=null;
			while(rs.next())
			{
				type=new Type();
				type.setTypeid(rs.getInt("typeid"));
				type.setTypename(rs.getString("typename"));
				if(type.getTypeid()==typeid)
				{
					typename=type.getTypename();
				}
			}
			return typename;
		}
		catch (SQLException SqlE) 
		{
			SqlE.printStackTrace();
			return null;
		} 
		catch (Exception E) 
		{
			E.printStackTrace();
			return null;
		}
		finally 
		{
			// 关闭连接，释放数据库资源：
			db_conn.CloseDB();
		}
	}
}