org.terrier.structures.postings
Class ProximityIterablePosting

java.lang.Object
  org.terrier.structures.postings.IterablePostingImpl
      org.terrier.structures.postings.ANDIterablePosting
          org.terrier.structures.postings.ProximityIterablePosting

All Implemented Interfaces:

Closeable, IterablePosting, Posting

public class ProximityIterablePosting
extends ANDIterablePosting

Implementation of an IterablePosting for block indices that returns only documents that match phases within a fixed window size.

Since:

3.6

Author:

Matteo Catena and Richard McCreadie

Field Summary

protected int

window

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

currentId, frequency, ips, termCount

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

EOL

Constructor Summary

ProximityIterablePosting(IterablePosting[] _ips, Pointer[] _p, int window)

Method Summary

protected boolean	calculateFrequency() returns true if the document matches
static IterablePosting	createProximityPostingList(Pointer[] ps, PostingIndex<Pointer> invIndex, int blockDistance)
static IterablePosting	createProximityPostingList(String[] terms, Lexicon<String> lex, PostingIndex<Pointer> invIndex, int blockDistance)

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

asWritablePosting, close, endOfPostings, getDocumentLength, getFrequency, getId, next, setId

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

next

Methods inherited from class java.lang.Object

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

Field Detail

window

protected int window

Constructor Detail

ProximityIterablePosting

public ProximityIterablePosting(IterablePosting[] _ips,
                                Pointer[] _p,
                                int window)
                         throws IOException

Throws:

IOException

Method Detail

calculateFrequency

protected boolean calculateFrequency()

Description copied from class: ANDIterablePosting

returns true if the document matches

Overrides:

calculateFrequency in class ANDIterablePosting

createProximityPostingList

public static IterablePosting createProximityPostingList(Pointer[] ps,
                                                         PostingIndex<Pointer> invIndex,
                                                         int blockDistance)
                                                  throws IOException

Throws:

IOException

createProximityPostingList

public static IterablePosting createProximityPostingList(String[] terms,
                                                         Lexicon<String> lex,
                                                         PostingIndex<Pointer> invIndex,
                                                         int blockDistance)
                                                  throws IOException

Throws:

IOException