Package org.terrier.structures.postings

Class PhraseIterablePosting

java.lang.Object

org.terrier.structures.postings.IterablePostingImpl

org.terrier.structures.postings.ANDIterablePosting

org.terrier.structures.postings.PhraseIterablePosting

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable, BlockPosting, IterablePosting, Posting

public class PhraseIterablePosting
extends ANDIterablePosting
implements BlockPosting

Implementation of an IterablePosting for block indices that returns only documents that match a multi-term phase.

Since:

3.5

Author:

Craig Macdonald

Field Summary

Fields inherited from class org.terrier.structures.postings.ANDIterablePosting

currentId, frequency, ips, termCount

Fields inherited from interface org.terrier.structures.postings.IterablePosting

END_OF_LIST, EOL

Constructor Summary

Constructors

Constructor	Description
PhraseIterablePosting(IterablePosting[] _ips, EntryStatistics[] _p, boolean recordPositions)
PhraseIterablePosting(IterablePosting[] _ips, Pointer[] _p, boolean recordPositions)

Method Summary

Modifier and Type	Method	Description
WritablePosting	asWritablePosting()	Copy this posting to one free of an iterator.
protected boolean	calculateFrequency()	returns true if the document matches
static IterablePosting	createPhrasePostingList(java.lang.String[] terms, Lexicon<java.lang.String> lex, PostingIndex<Pointer> invIndex, boolean savePositions)
static IterablePosting	createPhrasePostingList(Pointer[] ps, PostingIndex<Pointer> invIndex, boolean savePositions)
int[]	getPositions()	Return the positions of occurrences of the term in the current document.

Methods inherited from class org.terrier.structures.postings.ANDIterablePosting

close, endOfPostings, getDocumentLength, getFrequency, getId, next, next

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.terrier.structures.postings.Posting

getDocumentLength, getFrequency, getId, setId

Constructor Detail

PhraseIterablePosting

public PhraseIterablePosting(IterablePosting[] _ips,
                             EntryStatistics[] _p,
                             boolean recordPositions)
                      throws java.io.IOException

Throws:

java.io.IOException

PhraseIterablePosting

public PhraseIterablePosting(IterablePosting[] _ips,
                             Pointer[] _p,
                             boolean recordPositions)
                      throws java.io.IOException

Throws:

java.io.IOException

Method Detail

asWritablePosting

public WritablePosting asWritablePosting()

Description copied from interface: Posting

Copy this posting to one free of an iterator. Kind of like a clone.

Specified by:

asWritablePosting in interface Posting

Overrides:

asWritablePosting in class ANDIterablePosting

Returns:

an identical posting, but which can be manipulated free of this iterator

calculateFrequency

protected boolean calculateFrequency()

Description copied from class: ANDIterablePosting

returns true if the document matches

Overrides:

calculateFrequency in class ANDIterablePosting

getPositions

public int[] getPositions()

Description copied from interface: BlockPosting

Return the positions of occurrences of the term in the current document.

Specified by:

getPositions in interface BlockPosting

Returns:

the positions of occurrences of the term in the current document.

createPhrasePostingList

public static IterablePosting createPhrasePostingList(Pointer[] ps,
                                                      PostingIndex<Pointer> invIndex,
                                                      boolean savePositions)
                                               throws java.io.IOException

Throws:

java.io.IOException

createPhrasePostingList

public static IterablePosting createPhrasePostingList(java.lang.String[] terms,
                                                      Lexicon<java.lang.String> lex,
                                                      PostingIndex<Pointer> invIndex,
                                                      boolean savePositions)
                                               throws java.io.IOException

Throws:

java.io.IOException