[USER STORY] Generate a random, length 4, secret code for Mastermind

[jody]

User Story

As a player, I want the game to randomly generate a length 4 secret code so that each round is a fresh challenge.

Acceptance Criteria

• Code must be exactly 4 symbols, chosen from a specified symbol set (e.g., 0-9).
• Symbols may be repeated.
• The code is hidden from the player but accessible for testing.

Details

• Consider creating a method that returns a String (e.g., "1947", "#@$#").
• Use a built-in random number generator to help create novel codes.
• Write JUnit tests that confirm:
  • the code is exactly 4 symbols long.
  • all characters are symbols from the specified symbol set.
  • the same code is not generated more than twice in a sample size of 100.

[TylerAndreasen]

Working on this currently, but cannot move to In-Progress.

I have tests and code generation functioning. Given the current technique, calculations done through Wolfram Alpha imply that the odds of a code repeating on the scale of 100 codes is vanishingly unlikely (10000 choose 100 is ~6.5 * 10^241 unique combinations of spans of 100 codes).
Question: Should the Game track the last 100 codes given to the user to guarantee that they are never given the same code twice within 100 codes?

[jody]

Working on this currently, but cannot move to In-Progress.

Changed status to "In Progress"

[jody]

I have tests and code generation functioning.

How is the symbol set specified? Is it a parameter? If so, what is/are the data type(s) accepted?

[TylerAndreasen]

How is the symbol set specified? Is it a parameter? If so, what is/are the data type(s) accepted?

Currently I have the same char[] (0-9) hard-coded in the Game and Test classes.
Now that you have asked, I am reminded of a pattern I have seen you use with a default play() method without parameters and another with parameters. The latter of which being called by the former and by test methods. If you prefer the implementation to go in this direction, let me know.

Further, if you prefer I can open a PR to show the current code changes there.