private int id;
    private double balance;
    private static double interestRate = DEFAULT_INTEREST_RATE;
    private static int bankAccount = 1;
    ArrayList idUsers = new ArrayList();
    BankAccount(){
        this.id = bankAccount++;
    }
    static void setInterestRate(double interestRate)
    {
        BankAccount.interestRate = interestRate;
    }
    void deposit(double amount)
    {
        this.balance += amount;
    }
    double getInterest (int years)
    {
        return BankAccount.interestRate * years * this.balance;
    }
    void setIdUsers()
    {
        this.idUsers.add("Id"+ id);
    }




}