code: public static void register(Alphabet alphabet) {
          if (alphabetsByName.put(alphabet.getAlphabetName(), alphabet) != null)
              throw new IllegalStateException("Alphabet with this name is already registered.");
  
          if (alphabetsById.put(alphabet.getId(), alphabet) != null)
              throw new IllegalStateException("Alphabet with this id is already registered.");
      }
docs: Register new alphabet
  
  @param alphabet alphabet