## Uses of Class
org.apache.lucene.store.FilterDirectory

- Packages that use FilterDirectory
  Package | Description
  --- | ---
  org.apache.lucene.store | Binary i/o API, used for all index data.

- - ### Uses of FilterDirectory in org.apache.lucene.store

    Subclasses of FilterDirectory in org.apache.lucene.store
    Modifier and Type | Class | Description
    --- | --- | ---
    `class` | `LockValidatingDirectoryWrapper` | This class makes a best-effort check that a provided `Lock` is valid before any destructive filesystem operation.
    `class` | `NRTCachingDirectory` | Wraps a RAM-resident directory around any provided delegate directory, to be used during NRT search.
    `class` | `SleepingLockWrapper` | Directory that wraps another, and that sleeps and retries if obtaining the lock fails.
    `class` | `TrackingDirectoryWrapper` | A delegating Directory that records which files were written to and deleted.