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POHow to use one array on 2 different classes
 

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  1. POHow to use one array on 2 different classes
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    <p>I have 2 classes right now, the first class has the arraylist in it. But on the second class when I try to access the arraylist it keeps giving me the red line underneath saying that the variable doesn't exist. </p> <p>Here is class one...</p> <pre><code>public class BankMain { public static void main(String[] args) { // TODO Auto-generated method stub BankMain main = new BankMain(); menu(); } public static void cardNumbers(){ ArrayList&lt;Integer&gt; cardNum = new ArrayList&lt;Integer&gt;(); Scanner cards = new Scanner(System.in); Scanner input = new Scanner(System.in); Scanner keyboard = new Scanner(System.in); System.out.println("Please select a 5 digit card number"); cardNum.add(input.nextInt()); System.out.println("Thank you! You're card number is " +cardNum); System.out.println("Type 'c' to go back to main menu."); String value = keyboard.next(); if(value.equalsIgnoreCase("c")){ menu(); } else if (!keyboard.equals('c')){ System.out.println("Invalid Entry!"); } } public static void menu(){ System.out.println("What Would you like to do today?"); System.out.println(); System.out.println("Create Account = 1"); System.out.println("Login = 2"); System.out.println("Exit = 3"); query(); } public static void query(){ Scanner keyboard = new Scanner(System.in); double input = keyboard.nextInt(); if (input == 2){ BankMainPart2 main2 = new BankMainPart2(); System.out.println("Please enter your 5 digit card number."); main2.loginCard(); } else if (input == 1){ cardNumbers(); } else if (input == 3){ System.out.println("Thank you, have a nice day!"); System.exit(0); } } } </code></pre> <p>Here is the second class...</p> <pre><code>public class BankMainPart2 { public static void loginCard(){ if (cardNum.contains(name)) { } } } </code></pre> <p>I know I haven't entered anything in the if statement yet on the second class but I'm just trying to get my array list to work on both classes.</p>
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    1. USMadProgrammer
    1. USMatt McCarthy
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    1. COWhat exactly are you trying to do? cardNum is going to be private to the first class. Separate classes shouldn't share internal data like that.
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      1. POHow to use one array on 2 different classes
      1. USChristopher Armstrong
    2. COyou need to go over OOP again.
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      1. POHow to use one array on 2 different classes
      1. USelyashiv
    3. COI'm just trying to put more methods on the other class to split them up, I want to put like my bank account login methods in a separate class, but when using the second class I want it to be able to read the arraylist in the first class to check if the pin number exist in the arraylist. I'm building an ATM program.
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      1. POHow to use one array on 2 different classes
      1. USMatt McCarthy
 

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