* @param urlQueue The URL queue entry to insert.
     */
    @Override
    public void insert(final OpenSearchUrlQueue urlQueue) {
        try {
            super.insert(urlQueue, urlQueue.getId() == null ? OpType.CREATE : OpType.INDEX);
        } catch (final OpenSearchAccessException e) {
            final Throwable cause = e.getCause();
            if (cause != null && "VersionConflictEngineException".equals(cause.getClass().getSimpleName())) {

        httpClientContext.setAuthCache(authCache);
        httpClientContext.setCredentialsProvider(credentialsProvider);

        // Request Header
        final RequestHeader[] requestHeaders = { new RequestHeader("enctype", "multipart/form-data") };
        for (final RequestHeader requestHeader : requestHeaders) {
            if (requestHeader.isValid()) {