org.apache.lucene.index

Class MultiReader

java.lang.Object

org.apache.lucene.index.IndexReader

org.apache.lucene.index.CompositeReader

org.apache.lucene.index.BaseCompositeReader<IndexReader>

org.apache.lucene.index.MultiReader

All Implemented Interfaces:

Closeable

public class MultiReader
extends BaseCompositeReader<IndexReader>

A CompositeReader which reads multiple indexes, appending their content. It can be used to create a view on several sub-readers (like DirectoryReader) and execute searches on it.

For efficiency, in this API documents are often referred to via document numbers, non-negative integers which each name a unique document in the index. These document numbers are ephemeral -- they may change as documents are added to and deleted from an index. Clients should thus not rely on a given document having the same number between sessions.

NOTE: IndexReader instances are completely thread safe, meaning multiple threads can call any of its methods, concurrently. If your application requires external synchronization, you should not synchronize on the IndexReader instance; use your own (non-Lucene) objects instead.

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.lucene.index.IndexReader

IndexReader.ReaderClosedListener

Constructor Summary

Constructors

Constructor and Description
MultiReader(IndexReader... subReaders) Construct a MultiReader aggregating the named set of (sub)readers.
MultiReader(IndexReader[] subReaders, boolean closeSubReaders) Construct a MultiReader aggregating the named set of (sub)readers.

Method Summary

Methods

Modifier and Type	Method and Description
protected void	doClose() Implements close.

Methods inherited from class org.apache.lucene.index.BaseCompositeReader

docFreq, document, getDocCount, getSequentialSubReaders, getSumDocFreq, getSumTotalTermFreq, getTermVectors, maxDoc, numDocs, readerBase, readerIndex, totalTermFreq

Methods inherited from class org.apache.lucene.index.CompositeReader

getContext, toString

Methods inherited from class org.apache.lucene.index.IndexReader

addReaderClosedListener, close, decRef, document, document, ensureOpen, equals, getCombinedCoreAndDeletesKey, getCoreCacheKey, getRefCount, getTermVector, hasDeletions, hashCode, incRef, leaves, numDeletedDocs, open, open, open, open, open, registerParentReader, removeReaderClosedListener, tryIncRef

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

MultiReader

public MultiReader(IndexReader... subReaders)

Construct a MultiReader aggregating the named set of (sub)readers.

Note that all subreaders are closed if this Multireader is closed.

Parameters:

subReaders - set of (sub)readers

MultiReader

public MultiReader(IndexReader[] subReaders,
           boolean closeSubReaders)

Construct a MultiReader aggregating the named set of (sub)readers.

Parameters:

subReaders - set of (sub)readers; this array will be cloned.

closeSubReaders - indicates whether the subreaders should be closed when this MultiReader is closed

Method Detail

doClose

protected void doClose()
                throws IOException

Description copied from class: IndexReader

Implements close.

Specified by:

doClose in class IndexReader

Throws:

IOException