//                                                                         Poll Loop
    //                                                                         ===========

    /**
     * Periodic poll that sends a heartbeat, processes new events, and cleans up expired documents.
     */
    protected void poll() {
        try {
            sendHeartbeat();
        } catch (final Exception e) {

        cl.delegate = builder
        cl.call()
        def firstChild = parent.getFirstChild()
        builder.elements.each { element ->
            parent.insertBefore(element, firstChild)
        }
    }

    public static void addBefore(Node sibling, Closure cl) {
        DomBuilder builder = new DomBuilder(sibling.ownerDocument, null)
        cl.delegate = builder
        cl.call()
        def parent = sibling.parentNode

    public int[] batchInsert(List<FailureUrl> list, RequestOptionCall<BulkRequestBuilder> call) {
        return batchInsert(list, call, null);
    }

    public int[] batchInsert(List<FailureUrl> list, RequestOptionCall<BulkRequestBuilder> call,
            RequestOptionCall<IndexRequestBuilder> entityCall) {
        return doBatchInsert(new BulkList<>(list, call, entityCall), null);
    }

    public int[] batchInsert(List<RequestHeader> list, RequestOptionCall<BulkRequestBuilder> call) {
        return batchInsert(list, call, null);
    }

    public int[] batchInsert(List<RequestHeader> list, RequestOptionCall<BulkRequestBuilder> call,
            RequestOptionCall<IndexRequestBuilder> entityCall) {
        return doBatchInsert(new BulkList<>(list, call, entityCall), null);
    }

    public int[] batchInsert(List<ThumbnailQueue> list, RequestOptionCall<BulkRequestBuilder> call) {
        return batchInsert(list, call, null);
    }

    public int[] batchInsert(List<ThumbnailQueue> list, RequestOptionCall<BulkRequestBuilder> call,
            RequestOptionCall<IndexRequestBuilder> entityCall) {
        return doBatchInsert(new BulkList<>(list, call, entityCall), null);
    }

    public int[] batchInsert(List<Role> list, RequestOptionCall<BulkRequestBuilder> call) {
        return batchInsert(list, call, null);
    }

    public int[] batchInsert(List<Role> list, RequestOptionCall<BulkRequestBuilder> call,
            RequestOptionCall<IndexRequestBuilder> entityCall) {
        return doBatchInsert(new BulkList<>(list, call, entityCall), null);
    }

    public int[] batchUpdate(List<Role> list) {

    public int[] batchInsert(List<ClickLog> list, RequestOptionCall<BulkRequestBuilder> call) {
        return batchInsert(list, call, null);
    }

    public int[] batchInsert(List<ClickLog> list, RequestOptionCall<BulkRequestBuilder> call,
            RequestOptionCall<IndexRequestBuilder> entityCall) {
        return doBatchInsert(new BulkList<>(list, call, entityCall), null);
    }

    public int[] batchUpdate(List<ClickLog> list) {

        return batchInsert(list, call, null);
    }

    public int[] batchInsert(List<WebAuthentication> list, RequestOptionCall<BulkRequestBuilder> call,
            RequestOptionCall<IndexRequestBuilder> entityCall) {
        return doBatchInsert(new BulkList<>(list, call, entityCall), null);
    }

    public int[] batchInsert(List<AccessToken> list, RequestOptionCall<BulkRequestBuilder> call) {
        return batchInsert(list, call, null);
    }

    public int[] batchInsert(List<AccessToken> list, RequestOptionCall<BulkRequestBuilder> call,
            RequestOptionCall<IndexRequestBuilder> entityCall) {
        return doBatchInsert(new BulkList<>(list, call, entityCall), null);
    }

        return batchInsert(list, call, null);
    }

    public int[] batchInsert(List<ElevateWordToLabel> list, RequestOptionCall<BulkRequestBuilder> call,
            RequestOptionCall<IndexRequestBuilder> entityCall) {
        return doBatchInsert(new BulkList<>(list, call, entityCall), null);
    }