assertNotNull(result);
        assertFalse(result.isPresent());
    }

    @Test
    public void test_ofNullable_withCustomObject() {
        CustomTestObject testValue = new CustomTestObject("test", 123);
        OptionalEntity<CustomTestObject> result = OptionalUtil.ofNullable(testValue);

        assertNotNull(result);
        assertTrue(result.isPresent());
        assertEquals(testValue, result.get());

    public void test_sizeOf_customObjects() {
        // Test fallback case for custom objects (should return 16L)
        assertEquals(16L, MemoryUtil.sizeOf(new Object()));
        assertEquals(16L, MemoryUtil.sizeOf(new CustomTestObject()));
        assertEquals(16L, MemoryUtil.sizeOf(Boolean.TRUE));
        assertEquals(16L, MemoryUtil.sizeOf(Boolean.FALSE));
    }

    @Test
    public void test_sizeOf_complexNestedStructures() {