docs: @Nonnull
    public PasswordHash createUserDefaultPasswordHash (@Nullable final IPasswordSalt aSalt,
                                                       @Nonnull final String sPlainTextPassword)
    {
      ValueEnforcer.notNull (sPlainTextPassword, "PlainTextPassword");
  
      final IPasswordHashCreator aPHC = getDefaultPasswordHashCreator ();
      final String sPasswordHash = aPHC.createPasswordHash (aSalt, sPlainTextPassword);
      return new PasswordHash (aPHC.getAlgorithmName (), aSalt, sPasswordHash);
    }