// Deposit.java
 // Represents a deposit ATM transaction

public class Deposit extends Transaction
 {
     private double amount; // amount to deposit
     private Keypad keypad; // reference to keypad
     private DepositSlot depositSlot; // reference to deposit slot
     private final static int CANCELED = 0; // constant for cancel option

     // Deposit constructor
     public Deposit( int userAccountNumber, Screen atmScreen,
     BankDatabase atmBankDatabase, Keypad atmKeypad,
     DepositSlot atmDepositSlot )
     {
         // initialize superclass variables
         super( userAccountNumber, atmScreen, atmBankDatabase );

         // initialize references to keypad and deposit slot
         keypad = atmKeypad;
         depositSlot = atmDepositSlot;
     } // end Deposit constructor

 // perform transaction
    @Override
    public void execute()
    {
        BankDatabase bankDatabase = getBankDatabase(); // get reference
        Screen screen = getScreen(); // get reference

        amount = promptForDepositAmount(); // get deposit amount from user

 // check whether user entered a deposit amount or canceled
    if ( amount != CANCELED )
    {
        // request deposit envelope containing specified amount
        screen.displayMessage(
        "\nPlease insert a deposit envelope containing " );
        screen.displayDollarAmount( amount );
        screen.displayMessageLine( "." );

        // receive deposit envelope
        boolean envelopeReceived = depositSlot.isEnvelopeReceived();

        // check whether deposit envelope was received
        if ( envelopeReceived )
        {
            screen.displayMessageLine( "\nYour envelope has been " +
            "received.\nNOTE: The money just deposited will not " +
            "be available until we verify the amount of any " +
            "enclosed cash and your checks clear." );

            // credit account to reflect the deposit
            bankDatabase.credit( getAccountNumber(), amount );
        } // end if
        else //     deposit envelope not received
        {
            screen.displayMessageLine( "\nYou did not insert an " +
            "envelope, so the ATM has canceled your transaction." );
        } // end else
    } // end if
    else // user canceled instead of entering amount
    {
        screen.displayMessageLine( "\nCanceling transaction..." );
    } // end else
} // end method execute

 // prompt user to enter a deposit amount in cents
 private double promptForDepositAmount()
 {
     Screen screen = getScreen(); // get reference to screen

     // display the prompt
     screen.displayMessage( "\nPlease enter a deposit amount in " +
     "CENTS (or 0 to cancel): " );
     int input = keypad.getInput(); // receive input of deposit amount

     // check whether the user canceled or entered a valid amount
     if ( input == CANCELED )
           return CANCELED;
           else
           {
               return ( double ) input / 100; // return dollar amount
            } // end else
 } // end method promptForDepositAmount
} // end class Deposit