Bank.java

import java.util.ArrayList;

public class Bank {
  private static final int DEFAULT_BALANCE = Integer.MIN_VALUE;
  private String name;
  private ArrayList<Client> clients;

  public Bank(String name) {
    this.name = name;
    clients = new ArrayList<Client>();
  }

  public String getName() {
    return name;
  }

  // Add a client to the list of clients
  public void addClient(String cardNumber, String pin, int checkingBalance, int savingsBalance) {
    Client client = new Client(cardNumber, pin, checkingBalance, savingsBalance);
    clients.add(client);
  }

  // Check if the cardNumber exists
  public boolean cardExists(String cardNumber) {
    Client client = getClient(cardNumber);

    if (client != null) {
      return true;
    }

    return false;
  }

  // Check if the pin for a specific card is correct
  public boolean pinCorrect(String pin, String cardNumber) {
    Client client = getClient(cardNumber);

    if (client != null && client.getPin().equals(pin)) {
      return true;
    }

    return false;
  }

  // Get the client for a specific card number
  private Client getClient(String cardNumber) {
    for (Client client : clients) {
      if (client.getCardNumber().equals(cardNumber)) {
        return client;
      }
    }

    return null;
  }

  // Get the balance for a checking account given a card number
  public int getCheckingBalance(String cardNumber) {
    Client client = getClient(cardNumber);

    if (client != null) {
      return client.getCheckingBalance();
    }

    return DEFAULT_BALANCE;
  }

  // Get the balance for a savings account given a card number
  public int getSavingsBalance(String cardNumber) {
    Client client = getClient(cardNumber);

    if (client != null) {
      return client.getSavingsBalance();
    }

    return DEFAULT_BALANCE;
  }

  // Update checking balance given card number
  public void updateChecking(int quantity, String cardNumber) {
    Client client = getClient(cardNumber);

    if (client != null) {
      client.updateChecking(quantity);
    }
  }

  // Update savings balance given card number
  public void updateSavings(int quantity, String cardNumber) {
    Client client = getClient(cardNumber);

    if (client != null) {
      client.updateSavings(quantity);
    }
  }
}