Package org.apache.solr.cluster

This package contains the interfaces giving access to cluster state, including nodes, collections and the structure of the collections (shards and replicas). These interfaces allow separating external code contribution from the internal Solr implementations of these concepts to make usage simpler and to not require changes to external contributed code every time the internal abstractions are modified.

The top level abstraction is Cluster. The cluster is composed of Nodes. Indexes are stored in SolrCollections, composed of Shards whose actual copies on Nodes are called Replicas.