public @Nullable V get(@Nullable Object rowKey, @Nullable Object columnKey) {
    Map<C, V> row = safeGet(rowMap(), rowKey);
    return (row == null) ? null : safeGet(row, columnKey);
  }

  @Override
  public boolean isEmpty() {
    return size() == 0;
  }

  @Override
  public void clear() {
    Iterators.clear(cellSet().iterator());
  }

  @CanIgnoreReturnValue
  @Override

  abstract String normalizeWord(String word);

  String normalizeFirstWord(String word) {
    return normalizeWord(word);
  }

  private static String firstCharOnlyToUpper(String word) {
    return word.isEmpty()
        ? word
        : Ascii.toUpperCase(word.charAt(0)) + Ascii.toLowerCase(word.substring(1));
  }

        // Test with reflection to access protected method
        List<String> names = testFactory.loadDataStoreNameList();
        assertTrue(names.isEmpty() || names.size() >= 0); // Will be empty due to ResourceUtil static method
    }

    // Test loadDataStoreNameList with malformed XML
    public void test_loadDataStoreNameList_malformedXml() throws Exception {

    assertEquals(expected, CharSource.concat(ImmutableList.of(c1, c2, c3).iterator()).read());
    assertFalse(CharSource.concat(c1, c2, c3).isEmpty());

    CharSource emptyConcat = CharSource.concat(CharSource.empty(), CharSource.empty());
    assertTrue(emptyConcat.isEmpty());
  }

  public void testConcat_infiniteIterable() throws IOException {
    CharSource source = CharSource.wrap("abcd");

     * @throws SearchEngineClientException if the bulk indexing operation fails
     */
    public void sendDocuments(final SearchEngineClient searchEngineClient, final DocList docList) {
        if (docList.isEmpty()) {
            return;
        }
        final FessConfig fessConfig = ComponentUtil.getFessConfig();
        final SystemHelper systemHelper = ComponentUtil.getSystemHelper();

    for (K k : multimap().keySet()) {
      assertTrue(multimap().containsKey(k));
    }
  }

  public void testContainsKeyAgreesWithGet() {
    for (K k : sampleKeys()) {
      assertEquals(!multimap().get(k).isEmpty(), multimap().containsKey(k));
    }
  }

  public void testContainsKeyAgreesWithAsMap() {
    for (K k : sampleKeys()) {
      assertEquals(multimap().containsKey(k), multimap().asMap().containsKey(k));
    }
  }

        List<String> providers = RdmaProviderFactory.getAvailableProviders();
        assertNotNull(providers, "Available providers list should not be null");
        assertFalse(providers.isEmpty(), "Should have at least one available provider");
        assertTrue(providers.contains("TCP Fallback"), "Should include TCP fallback");
    }

     *             {@code localRepository} is {@code null} or {@code localRepository} is not a directory
     *             or parameter {@code mavenArtifacts} is {@code null} or
     *             {@code mavenArtifacts.isEmpty()} is {@code true}.
     */
    default void install(Session session, Collection<ProducedArtifact> artifacts) {
        install(ArtifactInstallerRequest.build(session, artifacts));
    }

   */
  @CanIgnoreReturnValue
  public static Set<Feature<?>> addImpliedFeatures(Set<Feature<?>> features) {
    Queue<Feature<?>> queue = new ArrayDeque<>(features);
    while (!queue.isEmpty()) {
      Feature<?> feature = queue.remove();
      for (Feature<?> implied : feature.getImpliedFeatures()) {
        if (features.add(implied)) {
          queue.add(implied);
        }
      }
    }

    suite.addTestSuite(EnumBiMapTest.class);
    return suite;
  }

  public void testCreate() {
    EnumBiMap<Currency, Country> bimap = EnumBiMap.create(Currency.class, Country.class);
    assertTrue(bimap.isEmpty());
    assertEquals("{}", bimap.toString());
    assertEquals(HashBiMap.create(), bimap);
    bimap.put(Currency.DOLLAR, Country.CANADA);
    assertEquals(Country.CANADA, bimap.get(Currency.DOLLAR));