15.3. About Lucene Directory
The Lucene Directory is the Input Output API for Apache Lucene to store the query indexes.
The most common Lucene Directory implementations used with JBoss Data Grid's Query Module are:
- Ram - stores the index in a local map to the node. This index cannot be shared.
- File system - stores the index in a locally mounted file system. This could be a network shared file system, however sharing in this manner is not recommended.
- JBoss Data Grid - stores the indexes in a different set of dedicated JBoss Data Grid caches. These caches can be configured as replicated or distributed in order to share the index between nodes.
The Query Module is not aware of where indexes are stored.
Note
The Lucene Directory provided by JBoss Data Grid is not limited to the Query Module. It can seamlessly replace any other requirement to store Lucene indexes where your application uses Lucene directly.
The JBoss Data Grid Query Module ships with several Lucene Directory implementations, and accepts third party implementations.
Important
The Query Module is currently only available as a Technical Preview for JBoss Data Grid 6.1.