SolrClient类型

HttpSolrClient - geared towards query-centric workloads, though also a good general-purpose client. Communicates directly with a single Solr node.

Http2SolrClient - async, non-blocking and general-purpose client that leverage HTTP/2. This class is experimental therefore its API’s might change or be removed in minor versions of SolrJ.

LBHttpSolrClient - balances request load across a list of Solr nodes. Adjusts the list of "in-service" nodes based on node health.

LBHttp2SolrClient - just like LBHttpSolrClient but using Http2SolrClient instead. This class is experimental therefore its API’s might change or be removed in minor versions of SolrJ.

CloudSolrClient - geared towards communicating with SolrCloud deployments. Uses already-recorded ZooKeeper state to discover and route requests to healthy Solr nodes.

ConcurrentUpdateSolrClient - geared towards indexing-centric workloads. Buffers documents internally before sending larger batches to Solr.

ConcurrentUpdateSolrClient - just like ConcurrentUpdateSolrClient but using Http2SolrClient instead. This class is experimental therefore its API’s might change or be removed in minor versions of SolrJ.