2

I'm doing an atm program and I'm having a hard time trying to figure out how to get it to actually deposit and withdraw. The balance starts off automatically as $0 but I can't get anything I type in to actually add on or subtract to it what am I doing wrong?

public class ATM {
static Scanner keyboard = new Scanner(System.in);
static String acctNum, pwd, result;
static double oldBalance, newBalance, deposit, withdraw;
static int choose;

public static void main(String[] args) {
    for (int run = 0; run < 3; run++) {
        System.out.println("Enter your account number");
        acctNum = keyboard.nextLine();
        System.out.println("Enter your account password");
        pwd = keyboard.nextLine();

        result = checkID(acctNum, pwd);
        if (!result.equals("ERROR")) {
            break;
        } else if (run == 2) {// you cannot try to log in anymore than 3
                                // times
            System.out.println("MAXIMUM TRIES EXCEEDED");
            return;
        }

    }
    menu();
}

public static String checkID(String acctNum, Object pwd) {
    String result = "ERROR";
    String a = "44567-5 mypassword 520.36";
    String b = "1234567-6 anotherpassword 48.20";
    String c = "4321-0 betterpassword 96.74";

    if (acctNum.equals("44567-5") && pwd.equals("mypassword")) {
        result = "520.36";
    } else if (acctNum.equals("1234567-6") && pwd.equals("anotherpassword")) {
        result = "48.20";
    } else if (acctNum.equals("4321-0") && pwd.equals("betterpassword")) {
        result = "96.74";
    }
    System.out.println(result);
    return result;
}

public static int menu() {
    System.out
            .println("Choose one of the following: \n1.Display Balance\n2.Deposit\n3.Withdraw\n4.Log Out");
    choose = keyboard.nextInt();

    if (choose == 1) {// 1. Display Balance
        displayBalance();
        menu();
        return 1;

    }
    if (choose == 2) {// 2. Deposit
        deposit();
        menu();
        return 2;

    }
    if (choose == 3) {// 3. Withdraw
        withdraw();
        menu();
        return 3;

    }
    if (choose == 4) {// 4. Log out
        System.out.println("You are logged out.");
        return 4;

    }
    if (choose <= 5) {// type in anything greater than 4 and you will get a
                        // system error
        System.out.println("System Error");
        menu();
        return 5;
    }
    if (choose >= 1) {// type in anything less than 1 and you will get a
                        // system error
        System.out.println("System Error");
        menu();
        return 6;
    }
    return choose;

}

public static double deposit() {
    System.out.println("How much would you like to deposit?");
    deposit = keyboard.nextInt();
    System.out.println((deposit + oldBalance)==newBalance);// deposit money into balance
    return 2;
}

public static double displayBalance() {
    System.out.println("Total balance is: $" + oldBalance);
    oldBalance = 0.00;
    return 1;
}

public static double withdraw() {
    System.out.println("How much would you like to withdraw?");
    withdraw = keyboard.nextInt();
    System.out.println(newBalance + withdraw);// withdraw money from balance
    return 3;
}

}

tcd9
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    You're not changing the values of balance...also, don't use recursive method calls for this, use a `do-while` loop instead (within your `menu` method) – MadProgrammer Nov 03 '14 at 00:57

3 Answers3

2

A few observations:

  1. Your class should not declare oldBalance, deposit, and withdrawal as global variables. The withdrawal method should not have access to the deposit variable and vice versa. It is a good programming practice to limit the scope of your variables as much as you can. Because a "deposit" variable is not really required outside this method, there is absolutely no reason to make it a global variable. The same cannot be said about "current balance." This variable is needed by all methods of the class: deposit, withdrawal, displayBalance, etc. Therefore, there is a good reason why to make it global (Still, if you can solve the problem with less scope, you should do that).

  2. I do not see why deposit() and withdrawal() need to return anything.

The simplest implementation of deposit() and withdrawal() is to simply add the user input to the currentBalance and save it in currentBalance.

public void deposit()
{
   Scanner input = new Scanner(System.in);
   System.out.printn("Enter deposit amount: );
   double amount = input.nextDouble();
   System.out.println("Your deposit amount: " + amount);
   currentBalance += amount;
   System.out.println("Your new balance is: + currentBalance);
}

public void withdrawal()
{
   Scanner input = new Scanner(System.in);
   System.out.printn("Enter withdrawal amount: );
   double amount = input.nextDouble();
   System.out.println("Your withdrawal amount: " + amount);
   currentBalance -= amount;
   System.out.println("Your new balance is: + currentBalance);
}

You are never saving the current balance. The == operator is a comparison operator, not an assignment operator. When you do something like this:

System.out.println((deposit + oldBalance)==newBalance);

Or like this:

System.out.println(newBalance + withdraw);

All you are doing is to pass the values to the println() method and not updating the variable that is supposed to hold the balance. In fact, the first one should print false (unless both deposit and oldBalance are zero). If you look at my code example, currentBalance += amount; is shorthand for currentBalance = currentBalance + amount; which means "add this amount to currentBalance and store it in currentBalance. Because I am reusing currentBalance, I eliminated the need for an oldBalance variable.

hfontanez
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0

Full Running Code

import java.awt.Container;
import java.awt.FlowLayout;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowEvent;
import java.awt.event.WindowAdapter;
import java.io.IOException;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JTextArea;
import java.util.ArrayList;
import java.util.Scanner;

/**
   A simulation of an automatic teller machine
*/

public class ATM  {
static Scanner keyboard = new Scanner(System.in);
static String acctNum, pwd, result;
static double oldBalance, newBalance, deposit, withdraw,currentBalance;
static int choose;

public static void main(String[] args) {
    for (int run = 0; run < 3; run++) {
        System.out.println("Enter your account number");
        acctNum = keyboard.nextLine();
        System.out.println("Enter your account password");
        pwd = keyboard.nextLine();

        result = checkID(acctNum, pwd);
        if (!result.equals("ERROR")) {
            break;
        } else if (run == 2) {// you cannot try to log in anymore than 3
                                // times
            System.out.println("MAXIMUM TRIES EXCEEDED");
            return;
        }

    }
    menu();
}

public static String checkID(String acctNum, Object pwd) {
    String result = "ERROR";
    String a = "44567-5 mypassword 520.36";
    String b = "1234567-6 anotherpassword 48.20";
    String c = "4321-0 betterpassword 96.74";

    if (acctNum.equals("2345") && pwd.equals("2345")) {
        result = "520.36";
    } else if (acctNum.equals("1234567-6") && pwd.equals("anotherpassword")) {
        result = "48.20";
    } else if (acctNum.equals("4321-0") && pwd.equals("betterpassword")) {
        result = "96.74";
    }
    System.out.println(result);
    return result;
}

public static int menu() {
    System.out.println("Choose one of the following: \n1.Display Balance\n2.Deposit\n3.Withdraw\n4.Log Out");
    choose = keyboard.nextInt();

    if (choose == 1) {// 1. Display Balance
        displayBalance();
        menu();
        return 1;

    }
    if (choose == 2) {// 2. Deposit
        deposit();
        menu();
        return 2;

    }
    if (choose == 3) {// 3. Withdraw
        withdraw();
        menu();
        return 3;

    }
    if (choose == 4) {// 4. Log out
        System.out.println("You are logged out.");
        return 4;

    }
    if (choose <= 5) {// type in anything greater than 4 and you will get a
                        // system error
        System.out.println("System Error");
        menu();
        return 5;
    }
    if (choose >= 1) {// type in anything less than 1 and you will get a
                        // system error
        System.out.println("System Error");
        menu();
        return 6;
    }
    return choose;

}

public static void deposit()
{
   Scanner input = new Scanner(System.in);
   System.out.println("Enter deposit amount:");
   double amount = input.nextDouble();
   System.out.println("Your deposit amount: " + amount);
   currentBalance += amount;
   System.out.println("Your new balance is: " + currentBalance);
}

public static double displayBalance() {
    System.out.println("Total balance is: $" + currentBalance);
    oldBalance = 0.00;
    return 1;
}

public static void withdraw()
{
   Scanner input = new Scanner(System.in);
   System.out.println("Enter withdrawal amount: ");
   double amount = input.nextDouble();
   System.out.println("Your withdrawal amount: " + amount);
   currentBalance -= amount;
   System.out.println("Your new balance is: " + currentBalance);
}
}
priyanka.sarkar
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0
    package shraam.bank.atm;

    import java.util.HashMap;
    import java.util.Map;
    import java.util.Scanner;
    import java.util.logging.Level;


    public class CalculateMoneyAtm {
        static Integer initialtwothousandrupees = 0;
        static Integer initialhundressrupees = 0;
        static Integer initialfiftyrupees = 0;
        static Integer initialtenrupees = 0;

        static Integer twothousandrupees = 0;
        static Integer hundressrupees = 0;
        static Integer fiftyrupees = 0;
        static Integer tenrupees = 0;
        static Integer totalAmount = 0;

        public static void main(String[] args) {

            ATMStatus atmStatus = new ATMStatus();
            getMoney(atmStatus);

        }//end of psvm

        public static void reRun(ATMStatus atmStatus) {
            MyLog.logit().info("Would u like to credit more money ? y/n");
            System.out.println("Would u like to credit more money ? y/n ");
            Scanner input = new Scanner(System.in);
            String choice = input.nextLine();
            if (choice.equals("y") || choice.equals("Y")) {
                getMoney(atmStatus);
            }
            if (choice.equals("n") || choice.equals("N")) {
                System.exit(1);
            } else {
                MyLog.logit().log(Level.SEVERE, "Invalid Input :"+choice);
                System.out.println("Invalid Input");
            }
            reRun(atmStatus);
        }

        public static void getMoney(ATMStatus atmStatus) {
            twothousandrupees = 0;
             hundressrupees = 0;
             fiftyrupees = 0;
             tenrupees = 0;
             totalAmount = 0;
            Integer amountInt=0;
            System.out.println("Currency Avaialbe in ATM");
            for (String key : atmStatus.getAvaialableMoney().keySet()) {
                System.out.println(atmStatus.getAvaialableMoney().get(key) + ":"
                        + key + " Notes");
            }

            for (String key : atmStatus.getAvaialableMoney().keySet()) {
                if (key.equals("2000"))
                    initialtwothousandrupees = atmStatus.getAvaialableMoney().get(key);
                if (key.equals("100"))
                    initialhundressrupees = atmStatus.getAvaialableMoney().get(key);
                if (key.equals("50"))
                    initialfiftyrupees = atmStatus.getAvaialableMoney().get(key);
                if (key.equals("10"))
                    initialtenrupees = atmStatus.getAvaialableMoney().get(key);
            }

            Scanner input = new Scanner(System.in);
            System.out.print("Enter Money > ");
            String amount = input.nextLine();
            try {
                try{
                 amountInt = Integer.parseInt(amount);
                 if(amountInt%10!=0)
                 {
                     System.out.println("Please enter amount in multiple of 10 ");
                     reRun(atmStatus);
                 }
                }catch(NumberFormatException ne){
                    MyLog.logit().log(Level.SEVERE, ne.getMessage());
                }
                System.out.print("Required Amount : ");
                System.out.println(amount);

                totalAmount = ((initialtwothousandrupees * 2000) + (initialhundressrupees * 100)
                        + (initialfiftyrupees * 50) + (initialtenrupees * 10));
                System.out
                        .println("Total Available amount in ATM : " + totalAmount);
                if (totalAmount < amountInt) {
                    System.out
                            .println("Total Avaialble amount is less in atm, Sorry for Inconvience");
                     reRun(atmStatus);
                }


                while (amountInt >= 2000 && initialtwothousandrupees > 0) {
                    initialtwothousandrupees = initialtwothousandrupees - 1;
                    twothousandrupees++;
                    amountInt = amountInt - 2000;
                }

                while (amountInt >= 100 && initialhundressrupees > 0) {
                    initialhundressrupees = initialhundressrupees - 1;
                    hundressrupees++;
                    amountInt = amountInt - 100;
                }

                while (amountInt >= 50 && initialfiftyrupees > 0) {
                    initialfiftyrupees = initialfiftyrupees - 1;
                    fiftyrupees++;
                    amountInt = amountInt - 50;
                }
                while (amountInt >= 10 && initialtenrupees > 0) {
                    initialtenrupees = initialtenrupees - 1;
                    tenrupees++;
                    amountInt = amountInt - 10;
                }
                if (amountInt > 0) {
                    System.out.println("No avalable balance in this unit");
                    reRun(atmStatus);
                } else {
                    System.out.println("Plz take your money in currency");
                    Map<String, Integer> avaialableMoney = new HashMap<String, Integer>();
                    System.out.println("     No of 2000:"+ twothousandrupees);
                    System.out.println("     No of 100:"+ hundressrupees);
                    System.out.println("     No of 50:"+ fiftyrupees);
                    System.out.println("     No of 10:"+ tenrupees);
                    avaialableMoney.put("2000", (initialtwothousandrupees));
                    avaialableMoney.put("100", (initialhundressrupees));
                    avaialableMoney.put("50", (initialfiftyrupees));
                    avaialableMoney.put("10", (initialtenrupees));
                    atmStatus.setAvaialableMoney(avaialableMoney);
                }
                //return amountInt;
            } catch (Exception e) {
                MyLog.logit().log(Level.SEVERE, e.getMessage());
            }
            System.out.println("Take your Amount = "+(2000*twothousandrupees+100*hundressrupees+50*fiftyrupees+10*tenrupees));
            reRun(atmStatus);

        }//end of getMoney
    }

    package shraam.bank.atm;

    import java.util.HashMap;
    import java.util.Map;
    import java.util.logging.Level;

    public class ATMStatus {
        public  Map<String,Integer> avaialableMoney=new HashMap<String,Integer>();
        public ATMStatus(){
                MyLog.logit().log(Level.INFO, " ATMStatus Initialized");

        avaialableMoney.put("2000", 10);
        avaialableMoney.put("100", 10);
        avaialableMoney.put("50", 10);
        avaialableMoney.put("10", 10);
        }
        public  Map<String, Integer> getAvaialableMoney() {
            return this.avaialableMoney;
        }
        public void setAvaialableMoney(Map<String, Integer> avaialableMoney) {
            this.avaialableMoney = avaialableMoney;
        }

    }

    package shraam.bank.atm;

    import java.io.IOException;
    import java.util.logging.FileHandler;
    import java.util.logging.Logger;
    import java.util.logging.SimpleFormatter;

    public class MyLog {

        public static Logger logit()
        {
            Logger logger = Logger.getLogger("MyLog");  
            FileHandler fh;  

            try {  

                // This block configure the logger with handler and formatter  
                fh = new FileHandler("C:/ArunTest/temp/MyLogFile.log");  
                logger.addHandler(fh);
                SimpleFormatter formatter = new SimpleFormatter();  
                fh.setFormatter(formatter);  

                // the following statement is used to log any messages  
                logger.info("My first log");  

            } catch (SecurityException e) {  
                e.printStackTrace();  
            } catch (IOException e) {  
                e.printStackTrace();  
            }
            return logger;  
        }

    }
//
output:
Nov 27, 2016 10:43:48 PM shraam.bank.atm.MyLog logit
INFO: My first log
Nov 27, 2016 10:43:48 PM shraam.bank.atm.ATMStatus <init>
SEVERE:  ATMStatus 
Currency Avaialbe in ATM
10:100 Notes
10:2000 Notes
10:50 Notes
10:10 Notes
Enter Money > 540
Required Amount : 540
Total Available amount in ATM : 21600
Plz take your money in currency
     No of 2000:0
     No of 100:5
     No of 50:0
     No of 10:4
Take your Amount = 540
Nov 27, 2016 10:43:52 PM shraam.bank.atm.MyLog logit
INFO: My first log
Nov 27, 2016 10:43:52 PM shraam.bank.atm.CalculateMoneyAtm reRun
INFO: Would u like to credit more money ? y/n
Would u like to credit more money ? y/n 
y
Currency Avaialbe in ATM
5:100 Notes
10:2000 Notes
10:50 Notes
6:10 Notes
Enter Money > 2060
Required Amount : 2060
Total Available amount in ATM : 21060
Plz take your money in currency
     No of 2000:1
     No of 100:0
     No of 50:1
     No of 10:1
Take your Amount = 2060
Nov 27, 2016 10:44:04 PM shraam.bank.atm.MyLog logit
INFO: My first log
Nov 27, 2016 10:44:04 PM shraam.bank.atm.CalculateMoneyAtm reRun
INFO: Would u like to credit more money ? y/n
Would u like to credit more money ? y/n
Arun
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