You are writing a small section of an ATM machine where you accept a string that is a password and accept it or reject it. If the user tries more than three times with a bad password the card is blocked and no password will be accepted until the resetPasswordAttempts method is called. The password must be fixed at "1234". Security is a priority!

The object to implement this is referred to as AtmPin and consists of the following public methods:

public AtmPin(String actualCode) - Creates an AtmPin object with the provided code as the actual PIN

public boolean verifyPinCode(String code) - Accepts a string which represents the password attempt. If the string matches the actual code provided in the constructor then the method returns true. Returns false when the code is bad OR when isBlocked() is true due to too many consecutive bad password attempts.

public boolean isBadPassword() - True when a bad pin is passed to acceptPinCode. Updated every time a password is passed to verifyPinCode. Note that you can have a good password but it is not accepted by the system (verifyPinCode returns false) since the password is blocked.

public boolean isBlocked() - If more than three consecutive attempts are made then the password is not accepted (verifyPinCode returns false) until resetPasswordAttempts is called.

public void resetPasswordAttempts() - Resets the number of attempts to zero.

Your Program.java should contain code to test your AtmPin object. Be sure to test the cases where you are blocked and send it a good password. It should still reject the password but isBadPassword will return false.

Getting Started

We are going to do this exercise by writing the object that solves the problem first (in a source file called AtmPin.java) and then testing it using code we write into Program.java. Using the techniques shown on the web page titled "How to Start Every Project in this Class" create a source file called AtmPin.java as well as a file called Program.java.

Don't forget to provide proper Javadoc documentation.

Your Program.java should contain code to test your AtmPin object. The test code for this project can be quite complex. Be sure to test the case where you get good passwords, bad passwords, and when you're locked out.

Once you've written your code run the code by single clicking on Program.java in the package explorer and selecting Run->Run from the menu or using the keyboard shortcut. Examine the output. Does it do what you want? If not, how can you modify the code to do what you want?