if (kid == null) {
            return;
        }

        if (children == null) {
            children = new MetadataTreeNode[nChildren];
        }

        children[index % nChildren] = kid;
    }

    // ------------------------------------------------------------------
    @Override
    public String toString() {
        return md == null ? "no metadata" : md.toString();
    }

        if (_conditionQuery != null) {
            QueryBuilder queryBuilder = _conditionQuery.getQuery();
            if (queryBuilder != null) {
                builder.setQuery(queryBuilder);
            }
            _conditionQuery.getFieldSortBuilderList().forEach(sort -> {
                builder.addSort(sort);
            });
        }

        if (_conditionAggregation != null) {

    }

    @AfterEach
    public void tearDown() throws IOException {
        if (manager != null) {
            manager.shutdown();
        }

        // Clean up system property
        System.clearProperty("jcifs.smb.client.handleStateDirectory");

        // Clean up temp directory
        if (tempDir != null && Files.exists(tempDir)) {
            Files.walk(tempDir)

	if !regexp.MustCompile("SELECT \\* FROM \\(SELECT .name. FROM .users. WHERE .users.\\..deleted_at. IS NULL\\) as u, \\(SELECT .name. FROM .pets. WHERE .pets.\\..deleted_at. IS NULL\\) as p WHERE .u.\\..deleted_at. IS NULL").MatchString(r.Statement.SQL.String()) {
		t.Errorf("Table with escape character, got %v", r.Statement.SQL.String())
	}

        } finally {
            // remove crawlerContext from thread
            CrawlingParameterUtil.setCrawlerContext(null);
            CrawlingParameterUtil.setUrlQueueService(null);
            CrawlingParameterUtil.setDataService(null);
        }
        log(logHelper, LogType.FINISHED_THREAD, crawlerContext);
    }

    /**
     * Adds sitemaps from robots.txt to the crawling queue.

        final ComponentDef<?> componentDef = prototypeMap.get(name);
        if (componentDef != null) {
            return (T) componentDef.get();
        }
        final ComponentHolder<?> componentHolder = singletonMap.get(name);
        if (componentHolder != null) {
            return (T) componentHolder.get();
        }
        return null;
    }

    @Override
    public boolean available() {
        return available;

     * @param hostname The parameter value of hostname. (NotNull)
     */
    public void setHostname(String hostname) {
        registerVariable("hostname", hostname);
    }

    /**
     * Set the value of jobname, used in parameter comment. <br>
     * Even if empty string, treated as empty plainly. So "IF pmb != null" is false if empty.

        return new CopyOptions().exclude(propertyNames);
    }

    /**
     * Returns a {@link CopyOptions} that excludes properties with {@literal null} values from the operation.
     *
     * @return A {@link CopyOptions} that excludes properties with {@literal null} values from the operation.
     * @see CopyOptions#excludeNull()
     */
    public static CopyOptions excludeNull() {
        return new CopyOptions().excludeNull();

        if (createdBy != null) {
            addFieldToSource(sourceMap, "createdBy", createdBy);
        }
        if (createdTime != null) {
            addFieldToSource(sourceMap, "createdTime", createdTime);
        }
        if (excludedPaths != null) {
            addFieldToSource(sourceMap, "excludedPaths", excludedPaths);
        }
        if (includedPaths != null) {

      if (entry.getKey() == null) {
        tryDrainReferenceQueues();
        return null;
      }
      V value = entry.getValue();
      if (value == null) {
        tryDrainReferenceQueues();
        return null;
      }

      return value;
    }

    /**
     * Performs routine cleanup following a read. Normally cleanup happens during writes, or from