Computing the name of the month
This exists already:

It's not the prettiest to use but it's there.

import java.time.*;
import java.time.format.*;
import java.util.*;

public class Example {

    public static void main(String[] args) {
        Month month = Month.of(2);
        System.out.printf("%s", month.getDisplayName(TextStyle.FULL, new Locale("en")));
        // outputs:
        // February
    }
}


Don't re-write code that's in your standard libraries :)