CIFSContext context = SingletonContext.getInstance();
        assertNotNull(context);
        assertNotNull(getSingletonInstanceViaReflection()); // Should be initialized now
    }

    @Test
    void testGetInstanceReturnsExistingInstance() throws CIFSException {
        // Test getInstance returns the existing instance
        SingletonContext.init(null);

        client = clientFactory.getClient(url);
        assertNotNull(client);
        assertTrue(client instanceof FileSystemClient);

        url = "smb:/home/hoge";
        client = clientFactory.getClient(url);
        assertNotNull(client);
        assertTrue(client instanceof SmbClient);

        url = "smb1:/home/hoge";
        client = clientFactory.getClient(url);
        assertNotNull(client);

        final Suggester suggester = Suggester.builder().build(runner.client(), id);

        assertNotNull(suggester);
        assertNotNull(suggester.client);
        assertNotNull(suggester.indexer());
        assertNotNull(suggester.getNormalizer());
        assertNotNull(suggester.getReadingConverter());
        assertNotNull(suggester.settings());
        assertTrue(!Strings.isNullOrEmpty(suggester.index));
    }

        assertNotNull(order);
        assertEquals(BucketOrder.count(false), order);

        facetInfo.sort = "term.DESC";
        order = facetInfo.getBucketOrder();
        assertNotNull(order);
        assertEquals(BucketOrder.key(false), order);

        facetInfo.sort = "key.ASC";
        order = facetInfo.getBucketOrder();
        assertNotNull(order);

                return "TestTransactionResponse";
            }
        };

        // When
        BufferCache.getBuffers(req, rsp);

        // Then
        assertNotNull(req.txn_buf, "Request buffer should be allocated");
        assertNotNull(rsp.txn_buf, "Response buffer should be allocated");
        assertEquals(SmbComTransaction.TRANSACTION_BUF_SIZE, req.txn_buf.length, "Request buffer should have correct size");

        // Test default constructor
        SuggestSettingsBuilder testBuilder = new SuggestSettingsBuilder();
        assertNotNull(testBuilder);
        assertEquals("fess_suggest", testBuilder.settingsIndexName);
        assertNotNull(testBuilder.timeoutSettings);
        assertNotNull(testBuilder.initialSettings);
        assertTrue(testBuilder.initialSettings.isEmpty());
    }

    @Test

        FessTimeResourceProvider yearProvider = new FessTimeResourceProvider(yearConfig);
        assertNotNull(yearProvider);
    }

    // Test timezone information
    public void test_timezoneInformation() {
        TimeZone defaultTz = TimeZone.getDefault();
        assertNotNull(defaultTz);
        assertNotNull(defaultTz.getID());
        assertTrue(defaultTz.getID().length() > 0);

        // Verify that each enum constant exists and can be referenced
        assertNotNull(ResolverType.RESOLVER_WINS, "RESOLVER_WINS should not be null.");
        assertNotNull(ResolverType.RESOLVER_BCAST, "RESOLVER_BCAST should not be null.");
        assertNotNull(ResolverType.RESOLVER_DNS, "RESOLVER_DNS should not be null.");
        assertNotNull(ResolverType.RESOLVER_LMHOSTS, "RESOLVER_LMHOSTS should not be null.");
    }

    /**

        assertTrue(request.isSigningEnforced());
        assertNotNull(request.getCapabilities());
        assertNotNull(request.getDialects());
        assertNotNull(request.getClientGuid());
        assertNotNull(request.getNegotiateContexts());
        assertNotNull(request.getPreauthSalt());

        // Verify data integrity

        assertNotNull(exception);
        assertEquals(message, exception.getMessage());
        assertNull(exception.getCause());
    }

    public void test_constructor_withNullMessage() {
        // Test with null message
        LdapConfigurationException exception = new LdapConfigurationException(null);

        assertNotNull(exception);
        assertNull(exception.getMessage());