# Package org.apache.cassandra.index

Interface Summary
Index: Consisting of a top level Index interface and two sub-interfaces which handle read and write operations, Searcher and Indexer respectively, this defines a secondary index implementation.
Index.IndexBuildingSupport: Provider of `SecondaryIndexBuilder` instances.
Index.Indexer: Listener for processing events emitted during a single partition update.
Index.Searcher: Performs the actual index lookup during execution of a ReadCommand.
IndexRegistry: The collection of all Index instances for a base table.

Class Summary
Index.CollatedViewIndexBuildingSupport: Default implementation of `IndexBuildingSupport` which uses a `ReducingKeyIterator` to obtain a collated view of the data in the SSTables.
SecondaryIndexBuilder: Manages building an entire index from column family data.
SecondaryIndexManager: Handles the core maintenance functionality associated with indexes: adding/removing them to or from a table, (re)building during bootstrap or other streaming operations, flushing, reloading metadata and so on.
TargetParser

Exception Summary
IndexNotAvailableException: Thrown if a secondary index is not currently available.