Master mind code gen

[emancilla77]

Closes: #44

[Copilot]

Pull Request Overview

This PR adds a CodeGenerator class to generate random 4-digit codes for the MasterMind game and introduces comprehensive unit tests to verify the code generation behavior.

• Adds CodeGenerator class with generateCode() method that creates random 4-digit codes using digits 0-9
• Adds MasterMindGameTest with three test cases validating code length, symbol validity, and randomness distribution

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 3 comments.

File	Description
MasterMindGame.java	Adds CodeGenerator class with static method to generate random 4-digit codes and imports java.util.*
MasterMindGameTest.java	New test file with three tests validating code generation properties

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[Copilot]

Corrected spelling of 'symbol' to 'symbols' in the error message.

Suggested change

	assertEquals(4, code.length(), "Code should be 4 symbol long");
	assertEquals(4, code.length(), "Code should be 4 symbols long");

[Copilot]

String concatenation in a loop is inefficient. Use StringBuilder instead to avoid creating multiple intermediate String objects.

Suggested change

	String code = "";
	for (int i=0; i < 4; i++) {
	int index = random.nextInt(numbers.length());
	code = code + numbers.charAt(index);
	}
	return code;
	StringBuilder code = new StringBuilder();
	for (int i=0; i < 4; i++) {
	int index = random.nextInt(numbers.length());
	code.append(numbers.charAt(index));
	}
	return code.toString();

[Copilot]

Creating a new Random instance on every method call is inefficient. Consider making it a static field or use ThreadLocalRandom.current() for better performance.

[jody]

Verify that coding conventions are followed.

Here's a report excerpt from Checkstyle (via ant checkstyle):

File ConsoleGameHub/MasterMindGame.java
Error Description :: Line
Using the '.*' form of import should be avoided - java.util.*.:: 2
Missing a Javadoc comment. :: 27 
Utility classes should not have a public or default constructor. :: 27
Missing a Javadoc comment. :: 28
'=' is not preceded with whitespace. :: 33
'=' is not followed by whitespace. :: 33
'4' is a magic number. :: 33

File ConsoleGameHub/MasterMindGameTest.java
Error Description :: Line
File does not end with a newline. :: 0
Using the '.*' form of import should be avoided - org.junit.jupiter.api.Assertions.*. :: 2
Using the '.*' form of import should be avoided - java.util.*. :: 4
Using the '.*' form of import should be avoided - java.util.regex.*. :: 5
Line has trailing spaces. :: 10