Question

JAVA PLEASE

Create a class called Account with the following instance data

• Integer id
• Double balance

Provides the following methods

• Default constructor (defaults balance to 100)
• Constructor with parameters for the ID and the starting balance
• Accessor and mutator methods for id and balance
• Method to perform a withdrawal
• Method to perform a deposit

Create a class called Bank which has an array of Account objects. This class will manage the accounts. It must provide methods

• Do withdrawal
• Do deposits
• Display the account balances
• Method to set the current account ID

Main will start by asking the user for an ID. Then it display a menu with options to Check Balance, Withdraw, Deposit and Exit. For the first 3 options the ID must be passed to the methods in Bank so it know which account to perform the transaction on. All of the operations will be on the same account until the user selects exit. The Exit option does not exit the program, the program prompts the user for another ID. Once the ID is entered the menu is display again.

The bank class will search the array for the account with the matching ID. If no matching account number then the user told the ID is invalid and is prompted again for a valid ID

Answer 1

Hey, I have attached the codes below. The codes has comments for explanation. If you have any problem, feel free to discuss it with me.

Account.java:

public class Account{
    private int id;
    private int balance;

    public Account() {
        balance = 100;
    }

    public Account(int id, int balance) {
        this.id = id;
        this.balance = balance;
    }

    public int getId() {
        return this.id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public int getBalance() {
        return this.balance;
    }

    public void setBalance(int balance) {
        this.balance = balance;
    }

    public boolean deposit(int amount){
        //returns if deposit is successfeull or not
        if(amount < 0){
            //negative amounts can not be deposited
            return false;
        }
        //add money to balance
        balance += amount;
        return true;
    }

    public boolean withdraw(int amount){
        if(amount > balance){
            //balace is insufficient
            return false;
        }
        //otherwise
        balance -= amount;
        return true;
    }

}

Code Screenshot:

Bank.java:

import java.util.Scanner;

public class Bank{
    private Account[] accounts;//stores accounts
    private int currentAccount; // the selected account
    //default constructor
    public Bank(){
        //allocate the array for 10 accounts
        accounts = new Account[10];
        //set id from 0 to 9
        for(int i = 0; i < 10 ; i++){
            accounts[i]= new Account(i , 100);
        }
        currentAccount = 0; //defualt 0 id
    }
    // constructor with given number of accounts
    public Bank(int n){
        //allocate the array for n accounts
        accounts = new Account[n];
        //set id from 0 to n-1
        for(int i = 0; i < n ; i++){
            accounts[i]= new Account(i , 100);
        }
        currentAccount = 0;
    }

    public void doDeposit(int amount){
        System.out.println("Deposit of $" + amount + " successfull: " + accounts[currentAccount].deposit(amount));
    }
    public void doWithdraw(int amount){
        System.out.println("Withdraw of $" + amount + " successfull: " + accounts[currentAccount].withdraw(amount));
    }

    public boolean setCurrentAccount(int id){
        if(id < 0 || id >= accounts.length){
            //id is out of range
            System.out.println("Account with given id does not exist");
            return false;
        }
        else{
            currentAccount = id;
            return true;
        }
    }

    public void displayBalance(){
        System.out.println("Account " + currentAccount + " has balance: $" + accounts[currentAccount].getBalance());
    }

    //main method
    public static void main(String[] args){
        //get a scanner object
        Scanner scn = new Scanner(System.in);
        //get a default bank object
        Bank bank = new Bank();
        while(true){
            System.out.print("Enter bank account id (Enter -1 to exit): ");
            int id = scn.nextInt();
            if(id == -1)
                return;
            //ask until a valid id is input
            while(!bank.setCurrentAccount(id)){
                System.out.print("Enter bank account id: ");
                id = scn.nextInt();
                if(id == -1)
                    return;
            }
            // got a valid id now chow menu
            System.out.println("1) Check Balance");
            System.out.println("2) Withdraw");
            System.out.println("3) Deposit");
            System.out.println("4) Exit");
            int amount;
            boolean exit = false;
            while(!exit){
                System.out.print("Choose: ");
                int choice = scn.nextInt();
                switch(choice){
                    case 1:
                        bank.displayBalance();
                        break;
                    case 2:
                        System.out.print("Enter amount: ");
                        amount = scn.nextInt();
                        bank.doWithdraw(amount);
                        break;
                    case 3:
                        System.out.print("Enter amount: ");
                        amount = scn.nextInt();
                        bank.doDeposit(amount);
                        break;
                    case 4:
                        exit = true; //set exit flag to true
                        break;
                    default:
                        //invalid choice
                        System.out.println("Invalid choice");
                }
            }
        }
    }
}

Code Screenshots:

Sample Output: