Iyana code review

[aiyanMA]

Your project is overall well made. I like how you guys grouped the similar class in different packages, giving a more organized look. Looking over the code and playing the game, I have some feedback:

1. I noticed you guys have implemented some comments but most classes did not have Javadoc. I recommend adding more comments to the public classes for better comprehension.
2. While looking over the PlayerPopup class, I noticed you guys used TextField() which allows users to enter any input for their username. In Label label = new Label, you guys should include a brief instruction in the label to clarify the format of acceptable usernames like asking for letters only, which I have added.
3. You guys should add input validations to prevent users from entering invalid characters like “/”, “:” etc, or numeric-only usernames. Using exceptions handling with a try-catch block would be a good way to implement this.