dbclient.java

《jsp编程起步》里面的所有源代码

package Db;

import java.sql.*;
import Bk.*;
import java.util.*;

public class DbClient{
	Connection Conn=null;
	Statement stmt=null;
	String sDBDriver = "com.jnetdirect.jsql.JSQLDriver";
	String sConnStr = "jdbc:JSQLConnect://localhost/mydb";
	
	public DbClient(){
		try{
			Class.forName("com.jnetdirect.jsql.JSQLDriver");
			Conn=DriverManager.getConnection(sConnStr,"sa","eren&candle");
			stmt=Conn.createStatement();
		}catch(Exception e){
			System.err.println(e);			
		}
	}
	public long getClientId(String name,String phone){
		ResultSet rs=null;
		long id=-1;
		try{	
			rs=stmt.executeQuery("SELECT * FROM client WHERE name='"+name+"' AND phone='"+phone+"'");
			while(rs.next()){
				id=rs.getLong("id");
			}
		}
		catch(Exception e){
			System.err.println(e);	
			return -1l;		
		}
		return id;
	}
	
	public long addClient(String name,String addr,String phone,float amount){
		long clientid=0;
		try{
			clientid=getClientId(name,phone);
			if(clientid==-1l)
				stmt.executeUpdate("INSERT INTO client VALUES('"+name+"','"+addr+"','"+phone+"','"+amount+"')");
			else {
				stmt.executeUpdate("UPDATE client SET amount=amount+"+amount+"WHERE id='"+clientid+"'");
			}
			clientid=getClientId(name,phone);
			
		}catch(Exception e){
			System.err.println(e);			
		}
		return clientid;
	}
	public boolean Client_Book(Vector vBuy,long clientid){
		long bookid;
		try{
			Enumeration eBook=vBuy.elements();
			while(eBook.hasMoreElements()){
				bookid=((Book)eBook.nextElement()).id;
				stmt.executeUpdate("INSERT INTO client_book VALUES('"+clientid+"','"+bookid+"',"+"1"+")");
			}
			
		}catch(Exception e){
			System.err.println(e);			
			return false;
		}
		return true;
	}
	public boolean destroy(){
		try{
			Conn.close();
		}catch(Exception e){
			return false;	
		}
		return true;
	}
}