org.apache.lucene.index

Class ReaderManager

java.lang.Object

org.apache.lucene.search.ReferenceManager<DirectoryReader>

org.apache.lucene.index.ReaderManager

All Implemented Interfaces:

Closeable

public final class ReaderManager
extends ReferenceManager<DirectoryReader>

Utility class to safely share DirectoryReader instances across multiple threads, while periodically reopening. This class ensures each reader is closed only once all threads have finished using it.

See Also:

SearcherManager

WARNING: This API is experimental and might change in incompatible ways in the next release.

Field Summary

Fields inherited from class org.apache.lucene.search.ReferenceManager

current

Constructor Summary

Constructors

Constructor and Description
ReaderManager(Directory dir) Creates and returns a new ReaderManager from the given Directory.
ReaderManager(IndexWriter writer, boolean applyAllDeletes) Creates and returns a new ReaderManager from the given IndexWriter.

Method Summary

Methods

Modifier and Type	Method and Description
protected void	decRef(DirectoryReader reference) Decrement reference counting on the given reference.
protected DirectoryReader	refreshIfNeeded(DirectoryReader referenceToRefresh) Refresh the given reference if needed.
protected boolean	tryIncRef(DirectoryReader reference) Try to increment reference counting on the given reference.

Methods inherited from class org.apache.lucene.search.ReferenceManager

acquire, afterClose, afterRefresh, close, maybeRefresh, maybeRefreshBlocking, release

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ReaderManager

public ReaderManager(IndexWriter writer,
             boolean applyAllDeletes)
              throws IOException

Creates and returns a new ReaderManager from the given IndexWriter.

Parameters:

writer - the IndexWriter to open the IndexReader from.

applyAllDeletes - If true, all buffered deletes will be applied (made visible) in the IndexSearcher / DirectoryReader. If false, the deletes may or may not be applied, but remain buffered (in IndexWriter) so that they will be applied in the future. Applying deletes can be costly, so if your app can tolerate deleted documents being returned you might gain some performance by passing false. See DirectoryReader.openIfChanged(DirectoryReader, IndexWriter, boolean).

Throws:

IOException - If there is a low-level I/O error

ReaderManager

public ReaderManager(Directory dir)
              throws IOException

Creates and returns a new ReaderManager from the given Directory.

Parameters:

dir - the directory to open the DirectoryReader on.

Throws:

IOException - If there is a low-level I/O error

Method Detail

decRef

protected void decRef(DirectoryReader reference)
               throws IOException

Description copied from class: ReferenceManager

Decrement reference counting on the given reference.

Specified by:

decRef in class ReferenceManager<DirectoryReader>

Throws:

IOException

refreshIfNeeded

protected DirectoryReader refreshIfNeeded(DirectoryReader referenceToRefresh)
                                   throws IOException

Description copied from class: ReferenceManager

Refresh the given reference if needed. Returns null if no refresh was needed, otherwise a new refreshed reference.

Specified by:

refreshIfNeeded in class ReferenceManager<DirectoryReader>

Throws:

IOException

tryIncRef

protected boolean tryIncRef(DirectoryReader reference)

Description copied from class: ReferenceManager

Try to increment reference counting on the given reference. Return true if the operation was successful.

Specified by:

tryIncRef in class ReferenceManager<DirectoryReader>