List<String> testValue = null;
        OptionalEntity<List<String>> result = OptionalUtil.ofNullable(testValue);

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

    @Test
    public void test_ofNullable_withMap() {
        Map<String, Object> testValue = new HashMap<>();
        testValue.put("key1", "value1");
        testValue.put("key2", 42);