transaction.h

里面有很多关于编程的实用例子

// Transaction.h
// Transaction abstract base class definition.
#ifndef TRANSACTION_H
#define TRANSACTION_H

class Screen; // forward declaration of class Screen
class BankDatabase; // forward declaration of class BankDatabase

class Transaction
{
public:
   // constructor initializes common features of all Transactions
   Transaction( int, Screen &, BankDatabase & );
    
   virtual ~Transaction() { } // virtual destructor with empty body
   
   int getAccountNumber() const; // return account number
   Screen &getScreen() const; // return reference to screen
   BankDatabase &getBankDatabase() const; // return reference to database

   // pure virtual function to perform the transaction
   virtual void execute() = 0; // overridden in derived classes
private:
   int accountNumber; // indicates account involved
   Screen &screen; // reference to the screen of the ATM
   BankDatabase &bankDatabase; // reference to the account info database
}; // end class Transaction

#endif // TRANSACTION_H


/**************************************************************************
 * (C) Copyright 1992-2009 by Deitel & Associates, Inc. and               *
 * Pearson Education, Inc. All Rights Reserved.                           *
 *                                                                        *
 * DISCLAIMER: The authors and publisher of this book have used their     *
 * best efforts in preparing the book. These efforts include the          *
 * development, research, and testing of the theories and programs        *
 * to determine their effectiveness. The authors and publisher make       *
 * no warranty of any kind, expressed or implied, with regard to these    *
 * programs or to the documentation contained in these books. The authors *
 * and publisher shall not be liable in any event for incidental or       *
 * consequential damages in connection with, or arising out of, the       *
 * furnishing, performance, or use of these programs.                     *
 **************************************************************************/