hit -> callback.apply(hit));
    }

    public static String getXContentString(final ToXContent xContent, final MediaType mediaType) {
        try {
            return XContentHelper.toXContent(xContent, mediaType, ToXContent.EMPTY_PARAMS, false).utf8ToString();
        } catch (final IOException e) {
            throw new IORuntimeException(e);
        }
    }

            final XContentBuilder builder = XContentFactory.jsonBuilder();
            builder.startObject();
            response.toXContent(builder, ToXContent.EMPTY_PARAMS);
            builder.endObject();
            builder.flush();
            try (OutputStream out = builder.getOutputStream()) {