StopwordsItem item1 = new StopwordsItem(1, "test");
        StopwordsItem item2 = new StopwordsItem(1, "test");

        item1.setNewInput("updated");
        item2.setNewInput("different");

        // Should still be equal based on original input
        assertTrue(item1.equals(item2));
    }

    public void test_toString() {
        // Test toString method

        assertFalse(item1.equals("word"));

        // Symmetry
        assertTrue(item1.equals(item2));
        assertTrue(item2.equals(item1));
    }

    public void test_equals_withNullInput() {
        // Test equals with null input
        ProtwordsItem item1 = new ProtwordsItem(1, null);
        ProtwordsItem item2 = new ProtwordsItem(2, null);
        ProtwordsItem item3 = new ProtwordsItem(1, "word");

        Collections.addAll(roleList, item1.getRoles());
        for (final String role : item2.getRoles()) {
            if (!roleList.contains(role)) {
                roleList.add(role);
            }
        }
        mergedItem.roles = roleList.toArray(new String[roleList.size()]);

        mergedItem.kinds = concatKinds(item1.kinds, item2.kinds);
        mergedItem.timestamp = item2.timestamp;

            SuggestItem mergedItem = item1;
            for (final SuggestItem item2 : items) {
                if (item1.equals(item2)) {
                    continue;
                }

                final String item2Id = item2.getId();
                if (item1Id.equals(item2Id)) {
                    mergedItem = SuggestItem.merge(mergedItem, item2);
                    mergedIdSet.add(item1Id);
                }
            }

        String[] text2 = { "item2" }; // Different text -> different ID
        String[][] readings2 = { { "read2" } };
        SuggestItem item2 = new SuggestItem(text2, readings2, null, 0L, 0L, 1.0f, null, null, null, SuggestItem.Kind.QUERY);

        SuggestItem.merge(item1, item2); // Should throw IllegalArgumentException
    }

        TestDictionaryItem item2 = new TestDictionaryItem();

        item1.id = 100L;
        item2.id = 200L;

        assertEquals(100L, item1.getId());
        assertEquals(200L, item2.getId());

        // Verify they don't affect each other
        item1.id = 300L;
        assertEquals(300L, item1.getId());
        assertEquals(200L, item2.getId());
    }

    public void test_constructor() {

        CharMappingItem item2 = new CharMappingItem(2L, inputs2, "output");
        CharMappingItem item3 = new CharMappingItem(3L, inputs3, "output");
        CharMappingItem item4 = new CharMappingItem(4L, inputs1, "different");

        // Same inputs and output should have same hash code
        assertEquals(item1.hashCode(), item2.hashCode());

        OptionalEntity<CharMappingItem> result2 = charMappingFile.get(2L);
        assertTrue(result2.isPresent());
        CharMappingItem item2 = result2.get();
        assertEquals(2L, item2.getId());
        assertArrayEquals(new String[] { "d", "e" }, item2.getInputs());
        assertEquals("f", item2.getOutput());

        OptionalEntity<CharMappingItem> result3 = charMappingFile.get(3L);
        assertFalse(result3.isPresent());
    }

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

    public void test_ofNullable_withList() {
        List<String> testValue = Arrays.asList("item1", "item2", "item3");
        OptionalEntity<List<String>> result = OptionalUtil.ofNullable(testValue);

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

        OptionalEntity<ProtwordsItem> item1 = protwordsFile.get(1);
        OptionalEntity<ProtwordsItem> item2 = protwordsFile.get(2);
        PagingList<ProtwordsItem> list = protwordsFile.selectList(0, 10);

        assertTrue(item1.isPresent());
        assertTrue(item2.isPresent());
        assertTrue(list.size() > 0);
    }

    public void test_reload_withLargeFile() throws Exception {