public void test_ofValues() {
        String[] values = { "value1", "value2" };
        StreamUtil.stream(values[0], values[1]).of(s -> {
            Object[] array = s.toArray();
            for (int i = 0; i < 2; i++) {
                assertEquals(values[i], array[i]);
            }
        });
    }

    public void test_ofNull() {
        assertEquals(0, (int) StreamUtil.stream().get(s -> s.toArray().length));