db_type.java

精通Jsp-Web开发技术与典型应用 源码

package ch24.JavaBean;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Vector;

import ch24.JavaBean.DB_Conn;
import ch24.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();
		}
	}

    public  Vector list_type()
   {
	    db_conn.ConnectDB();
	    ResultSet rs=null;
	    try
	    {
		    String sql="select * from type";
		    sql = new String(sql.getBytes("ISO8859-1"), "GB2312");
	        rs=db_conn.sm.executeQuery(sql);
	        Type type=null;
	        Vector vector=new Vector();
	        //ResultSet指针最初位于第一行之前，调用next方法使下一行成为当前行
		    while(rs.next()) 
		    {   
			    type = new Type();
			    type.setTypeid(rs.getInt("typeid"));
			    type.setTypename(rs.getString("typename"));
			    type.setTypedesc(rs.getString("typedesc"));
			    //向Vector矢量中添加对象goods
			    vector.addElement(type);
		    }
		    return vector;
	    }
	    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();
	    }
   }
    public  Vector list_type(String key)
    {
 	    db_conn.ConnectDB();
 	    ResultSet rs=null;
 	    try
 	    {
 		    String sql="select * from type where typename like"+"'"+"%"+key+"%"+"'";
 	        rs=db_conn.sm.executeQuery(sql);
 	        Type type=null;
 	        Vector vector=new Vector();
 	        //ResultSet指针最初位于第一行之前，调用next方法使下一行成为当前行
 		    while(rs.next()) 
 		    {   
 			    type = new Type();
 			    type.setTypeid(rs.getInt("typeid"));
 			    type.setTypename(rs.getString("typename"));
 			    type.setTypedesc(rs.getString("typedesc"));
 			    //向Vector矢量中添加对象goods
 			    vector.addElement(type);
 		    }
 		    return vector;
 	    }
 	    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();
 	    }
    }
    public Type list_type(int typeid)
    {
    	db_conn.ConnectDB();
    	ResultSet rs=null;
    	try
    	{
    		Type type=new Type();
    		String sql="select * from type where typeid="+typeid;
    		rs=db_conn.sm.executeQuery(sql);
    		if(rs.next())
    		{
    			type.setTypeid(rs.getInt("typeid"));
    			type.setTypename(rs.getString("typename"));
    			type.setTypedesc(rs.getString("typedesc"));
    		}
    		return type;
    	}
    	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();
 	    }
    }
    public int delete_type(int typeid)
    {
    	db_conn.ConnectDB();
    	try
    	{
    		String sql="delete from type where typeid="+typeid;
    		int i=db_conn.sm.executeUpdate(sql);
    		return i;
    	}
    	catch (SQLException SqlE) 
 	    {
 		    SqlE.printStackTrace();
 		    return -1;
 	    } 
 	    catch (Exception E) 
 	    {
 		    E.printStackTrace();
 		    return -2;
 	    }
 	    finally 
 	    {
 		    // 关闭连接，释放数据库资源：
 		    db_conn.CloseDB();
 	    }
    }
    public int inserttype(Type type)
    {
    	db_conn.ConnectDB();
    	try
    	{
    		String sql="insert into type(typename,typedesc) values("+"'"+
    		type.getTypename()+"'"+","+"'"+
    		type.getTypedesc()+"')";
    		sql = new String(sql.getBytes("ISO8859-1"), "GB2312");
    		int i=db_conn.sm.executeUpdate(sql);
    		return i;
    	}
    	catch (SQLException SqlE) 
 	    {
 		    SqlE.printStackTrace();
 		    return -1;
 	    } 
 	    catch (Exception E) 
 	    {
 		    E.printStackTrace();
 		    return -2;
 	    }
 	    finally 
 	    {
 		    // 关闭连接，释放数据库资源：
 		    db_conn.CloseDB();
 	    }
    }
    public int updatetype(Type type)
    {
    	db_conn.ConnectDB();
    	try
    	{
    		String sql="update type set typeid="+type.getTypeid()+
    		",typename='"+type.getTypename()+"',typedesc='"+
    		type.getTypedesc()+"'"+" where typeid="+type.getTypeid();
    		sql = new String(sql.getBytes("ISO8859-1"), "GB2312");
    		int i=db_conn.sm.executeUpdate(sql);
    		return i;
    	}
    	catch (SQLException SqlE) 
 	    {
 		    SqlE.printStackTrace();
 		    return -1;
 	    } 
 	    catch (Exception E) 
 	    {
 		    E.printStackTrace();
 		    return -2;
 	    }
 	    finally 
 	    {
 		    // 关闭连接，释放数据库资源：
 		    db_conn.CloseDB();
 	    }
    }
}