Package org.terrier.matching.matchops

Class Operator

java.lang.Object

org.terrier.matching.matchops.Operator

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable

Direct Known Subclasses:

DateRangeOp, MultiTermOp, SingleTermOp

public abstract class Operator
extends java.lang.Object
implements java.io.Serializable, java.lang.Cloneable

A match op is a possible query "term" in the query

Since:

5.0

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
protected static boolean	IGNORE_LOW_IDF_TERMS

Constructor Summary

Constructors

Constructor	Description
Operator()

Method Summary

Modifier and Type	Method	Description
Operator	clone()
boolean	equals(java.lang.Object _o)
abstract MatchingEntry	getMatcher(MatchingQueryTerms.QueryTermProperties qtp, Index index, Lexicon<java.lang.String> lex, PostingIndex<Pointer> inv, CollectionStatistics collStats)	get an entry for matching for this query op.
abstract org.apache.commons.lang3.tuple.Pair<EntryStatistics,IterablePosting>	getPostingIterator(Index index)	get posting iterator for this query op.
int	hashCode()
static Operator	parse(java.lang.String stringRep)
abstract java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

IGNORE_LOW_IDF_TERMS

protected static boolean IGNORE_LOW_IDF_TERMS

Constructor Detail

Operator

public Operator()

Method Detail

toString

public abstract java.lang.String toString()

Overrides:

toString in class java.lang.Object

getMatcher

public abstract MatchingEntry getMatcher(MatchingQueryTerms.QueryTermProperties qtp,
                                         Index index,
                                         Lexicon<java.lang.String> lex,
                                         PostingIndex<Pointer> inv,
                                         CollectionStatistics collStats)
                                  throws java.io.IOException

get an entry for matching for this query op. calls getPostingIterator() internally

Throws:

java.io.IOException

equals

public boolean equals(java.lang.Object _o)

Overrides:

equals in class java.lang.Object

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

clone

public Operator clone()

Overrides:

clone in class java.lang.Object

getPostingIterator

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

get posting iterator for this query op.

Returns:

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

Throws:

java.io.IOException

parse

public static Operator parse(java.lang.String stringRep)