code: public static Generator<Vector2D> createNormal()
    {
      return new Vector2DGenerator(PrimitiveGenerators.doubles(
        GeneratorConstants.BOUND_NORMAL_DOUBLE_LOWER,
        GeneratorConstants.BOUND_NORMAL_DOUBLE_UPPER
      ));
    }
docs: Create a generator initialized with a default component generator that
  produces values in the range {@code [-1.0, 1.0]}.
  
  @return A generator