assertNull(emptyIterator.next(), "Final next call");
    }

    @Test
    @DisplayName("EmptyIterator should be lightweight and efficient")
    void testPerformanceCharacteristics() {
        // When - create many instances quickly
        long startTime = System.currentTimeMillis();

        for (int i = 0; i < 10000; i++) {
            EmptyIterator iterator = new EmptyIterator();