default RequestIndexer createBulkProcessorIndexer(
            BulkProcessor bulkProcessor,
            boolean flushOnCheckpoint,
            AtomicLong numPendingRequestsRef) {
		return new org.apache.flink.streaming.connectors.elasticsearch.PreElasticsearch6BulkProcessorIndexer(
			bulkProcessor,
			flushOnCheckpoint,
			numPendingRequestsRef);
	}
Creates a {@link RequestIndexer} that is able to work with {@link BulkProcessor} binary compatible.
elasticsearch5-xh/elasticsearch5-xh-sink/src/main/java/org/apache/flink/streaming/connectors/elasticsearch/ElasticsearchApiCallBridge.java