Package org.terrier.realtime.multi

Class MultiIndex

java.lang.Object

org.terrier.structures.Index

org.terrier.realtime.multi.MultiIndex

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable

Direct Known Subclasses:

IncrementalIndex

public class MultiIndex
extends Index

The central MultiIndex structure. MultiIndex is a wrapper around multiple indices such that they appear as one single index. Matching over a MultiIndex can either be performed by a normal matching across all index shards or using a special selective matching class that only uses a subset of the shards this contains.

Properties

• multiindex.selectivematching - What policy should be used to perform matching. Two options are supported: all (default), mostrecent

Since:

4.0

Author:

Richard McCreadie, Stuart Mackie

Nested Class Summary

Nested classes/interfaces inherited from class org.terrier.structures.Index

Index.DirectIndexRef

Field Summary

Fields

Modifier and Type	Field	Description
protected boolean	blocks
protected boolean	fields
protected java.util.List<Index>	indices
protected IncrementalSelectiveMatching	selectiveMatchingPolicy	Selective Matching policy, a policy for accessing only subsets of the indices within this multi-index.

Constructor Summary

Constructors

Constructor	Description
MultiIndex(Index[] indices, boolean blocks, boolean fields)	Constructor.

Method Summary

Modifier and Type	Method	Description
void	close()
void	flush()
CollectionStatistics	getCollectionStatistics()	Get the collection statistics
PostingIndex<?>	getDirectIndex()	Return the DirectIndex associated with this index
DocumentIndex	getDocumentIndex()	Return the DocumentIndex associated with this index
IndexRef	getIndexRef()	Returns a direct IndexRef to this index
java.lang.Object	getIndexStructureInputStream(java.lang.String structureName)	Not implemented.
PostingIndex<?>	getInvertedIndex()	Returns the InvertedIndex to use for this index
Index	getIthShard(int i)
Lexicon<java.lang.String>	getLexicon()	Return the Lexicon associated with this index
MetaIndex	getMetaIndex()	Get the Meta Index structure
int	getNumberOfShards()	Returns the number of index shards that this incremental index contains
boolean	hasIndexStructure(java.lang.String structureName)	Returns true iff the structure exists
java.lang.String	toString()

Methods inherited from class org.terrier.structures.Index

createIndex, createIndex, getEnd, getIndexStructure, getStart, hasIndexStructureInputStream, makeDirectIndexRef, setIndexLoadingProfileAsRetrieval

Methods inherited from class java.lang.Object

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

Field Detail

indices

protected java.util.List<Index> indices

selectiveMatchingPolicy

protected IncrementalSelectiveMatching selectiveMatchingPolicy

Selective Matching policy, a policy for accessing only subsets of the indices within this multi-index.

blocks

protected boolean blocks

fields

protected boolean fields

Constructor Detail

MultiIndex

public MultiIndex(Index[] indices,
                  boolean blocks,
                  boolean fields)

Constructor.

Method Detail

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

getIndexRef

public IndexRef getIndexRef()

Description copied from class: Index

Returns a direct IndexRef to this index

Specified by:

getIndexRef in class Index

getLexicon

public Lexicon<java.lang.String> getLexicon()

Return the Lexicon associated with this index

Specified by:

getLexicon in class Index

getInvertedIndex

public PostingIndex<?> getInvertedIndex()

Returns the InvertedIndex to use for this index

Specified by:

getInvertedIndex in class Index

getMetaIndex

public MetaIndex getMetaIndex()

Get the Meta Index structure

Specified by:

getMetaIndex in class Index

getDocumentIndex

public DocumentIndex getDocumentIndex()

Return the DocumentIndex associated with this index

Specified by:

getDocumentIndex in class Index

getCollectionStatistics

public CollectionStatistics getCollectionStatistics()

Get the collection statistics

Specified by:

getCollectionStatistics in class Index

getDirectIndex

public PostingIndex<?> getDirectIndex()

Description copied from class: Index

Return the DirectIndex associated with this index

Specified by:

getDirectIndex in class Index

hasIndexStructure

public boolean hasIndexStructure(java.lang.String structureName)

Description copied from class: Index

Returns true iff the structure exists

Overrides:

hasIndexStructure in class Index

getIndexStructureInputStream

public java.lang.Object getIndexStructureInputStream(java.lang.String structureName)

Not implemented.

Overrides:

getIndexStructureInputStream in class Index

close

public void close()
           throws java.io.IOException

Specified by:

close in interface java.lang.AutoCloseable

Specified by:

close in interface java.io.Closeable

Overrides:

close in class Index

Throws:

java.io.IOException

flush

public void flush()
           throws java.io.IOException

Throws:

java.io.IOException

getIthShard

public Index getIthShard(int i)

getNumberOfShards

public int getNumberOfShards()

Returns the number of index shards that this incremental index contains

Returns:

integer number of shards