Package org.terrier.matching.matchops

Class PrefixTermOp

java.lang.Object

org.terrier.matching.matchops.Operator

org.terrier.matching.matchops.MultiTermOp

org.terrier.matching.matchops.SynonymOp

org.terrier.matching.matchops.PrefixTermOp

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable

Direct Known Subclasses:

FuzzyTermOp

public class PrefixTermOp
extends SynonymOp

A synonym class that matches terms with a common prefix in the lexicon.

Since:

5.0

Author:

Craig Macdonald

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
protected static org.slf4j.Logger	logger
static java.lang.String	STRING_PREFIX

Fields inherited from class org.terrier.matching.matchops.Operator

IGNORE_LOW_IDF_TERMS

Constructor Summary

Constructors

Constructor	Description
PrefixTermOp(java.lang.String searchString)

Method Summary

Modifier and Type	Method	Description
protected java.lang.String	getEndString(java.lang.String termLo)
org.apache.commons.lang3.tuple.Pair<EntryStatistics,IterablePosting>	getPostingIterator(Index index)	get posting iterator for this query op.
protected java.lang.String	getStartString(java.lang.String search)
java.lang.String	toString()

Methods inherited from class org.terrier.matching.matchops.SynonymOp

createFinalPostingIterator, mergeStatistics

Methods inherited from class org.terrier.matching.matchops.MultiTermOp

addStatistics, clone, getConstituents, getMatcher

Methods inherited from class org.terrier.matching.matchops.Operator

equals, hashCode, parse

Methods inherited from class java.lang.Object

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

Field Detail

logger

protected static final org.slf4j.Logger logger

STRING_PREFIX

public static final java.lang.String STRING_PREFIX

See Also:

Constant Field Values

Constructor Detail

PrefixTermOp

public PrefixTermOp(java.lang.String searchString)

Method Detail

toString

public java.lang.String toString()

Overrides:

toString in class SynonymOp

getStartString

protected java.lang.String getStartString(java.lang.String search)

getEndString

protected java.lang.String getEndString(java.lang.String termLo)

getPostingIterator

public org.apache.commons.lang3.tuple.Pair<EntryStatistics,IterablePosting> getPostingIterator(Index index)
                                                                                              throws java.io.IOException

Description copied from class: Operator

get posting iterator for this query op.

Overrides:

getPostingIterator in class MultiTermOp

Returns:

Pair, but Pair.of(null,null) if term not found

Throws:

java.io.IOException