public String getIndexFieldSegment() {
                return "segment";
            }

            @Override
            public String get(String key) {
                // Return empty string instead of null
                return "";
            }
        };

        ComponentUtil.setFessConfig(fessConfig);

        // Initialize QueryFieldConfig

        healthyChannel.setState(ChannelState.ESTABLISHED);

        // Use reflection or package-private method to add channel for testing
        // For now, just test the empty case
        assertEquals(0, channelManager.getHealthyChannels().size());
    }

    @Test
    void testChannelSelection() {
        try {
            channelManager.selectChannel(mockMessage);

    /**
     * Return the sAMAccountName of this SID unless it could not
     * be resolved in which case the numeric RID is returned. If this
     * SID is a domain SID, this method will return an empty String.
     *
     * @return the account name
     */
    String getAccountName();

    /**
     * Return the domain name of this SID unless it could not be

        assertFalse(Features.deployBuildPom(properties));
    }

    @Test
    void testDeployBuildPomWithEmptyString() {
        // Test that empty string defaults to false
        Map<String, Object> properties = Map.of(Constants.MAVEN_DEPLOY_BUILD_POM, "");
        assertFalse(Features.deployBuildPom(properties));
    }

    @Test

        final String filename = params.get(ExtractData.RESOURCE_NAME_KEY);
        if (StringUtil.isEmpty(filename) && is == null) {
            throw new MimeTypeException("The filename and input stream is empty.");
        }

        final Metadata metadata = new Metadata();
        metadata.add(ExtractData.RESOURCE_NAME_KEY, normalizeFilename(filename));

        try {
            if (useFilename) {

@GwtCompatible
@Immutable(containerOf = {"R", "C", "V"})
final class SparseImmutableTable<R, C, V> extends RegularImmutableTable<R, C, V> {
  static final ImmutableTable<Object, Object, Object> EMPTY =
      new SparseImmutableTable<>(
          ImmutableList.<Cell<Object, Object, Object>>of(), ImmutableSet.of(), ImmutableSet.of());

  private final ImmutableMap<R, ImmutableMap<C, V>> rowMap;

  private static final int REPETITIONS = 3;

  private final List<List<Object>> equalityGroups = new ArrayList<>();
  private final RelationshipTester.ItemReporter itemReporter;

  /** Constructs an empty EqualsTester instance */
  public EqualsTester() {
    this(/* itemReporter= */ Item::toString);
  }

  EqualsTester(RelationshipTester.ItemReporter itemReporter) {
    this.itemReporter = checkNotNull(itemReporter);

            return advance(true);
        }
        return null;
    }

    /**
     * Opens the enumeration and returns the first entry.
     *
     * @return the first file entry, or null if empty
     * @throws CIFSException if an error occurs during opening
     */
    protected abstract FileEntry open() throws CIFSException;

    /**
     * Checks if the enumeration is complete.
     *

}

// delete all cache data on disks.
func (m *metacache) delete(ctx context.Context) {
	if m.bucket == "" || m.id == "" {
		bugLogIf(ctx, fmt.Errorf("metacache.delete: bucket (%s) or id (%s) empty", m.bucket, m.id))
		return
	}
	objAPI := newObjectLayerFn()
	if objAPI == nil {
		internalLogIf(ctx, errors.New("metacache.delete: no object layer"))
		return
	}
	ez, ok := objAPI.(deleteAllStorager)

  // value records whether the graph has been mutated since the corresponding
  // session has been run (this is detected in RecordMutation function). If the
  // string is empty, no mutation has occurred. Otherwise the string is a
  // description of the mutation suitable for returning to the user.
  //
  // Sessions are added to this map in TF_NewSession, and removed in
  // TF_DeleteSession.