// A class with data for a savings account.
// This first example illustrates how to define a class with non-public
// instance variables and some public methods.
//
// API of this class:
//
// public class Account
// {
//    public Account (String n, double b) 
//    public String getname()
//    public double getbalance()
//    public void withdraw (double amount)
//    public void deposit (double amount)
//    public double monthactivity ()
// }

public class Account
{ // instance variables
  String name;
  double balance;
  static double interestrate = .04;

  // constructor method is used to initialize instance variables
  public Account (String n, double b)
  { name = n;
    balance = b;
  }

  // accessor methods
  public String getname()
  { return name; }

  public double getbalance()
  { return balance; }

  // other methods
  public void withdraw (double amount)
  { 
    if ((balance - amount) > 0)
    { balance -= amount;
    }
    else { } // later will return exception "insufficient funds"
  }

  public void deposit (double amount)
  {  balance += amount; }

  // returns monthly interest and updates balance
  public double monthactivity()
  { double interest = (balance * interestrate)/12;
    balance += interest;
    return interest;
  }
}