org.terrier.structures
Class BlockDirectIndex

java.lang.Object
  org.terrier.structures.BitPostingIndex
      org.terrier.structures.DirectIndex
          org.terrier.structures.BlockDirectIndex

All Implemented Interfaces:

java.io.Closeable, PostingIndex<BitIndexPointer>

public class BlockDirectIndex
extends DirectIndex

Extended direct index that saves both block and field information about the terms that appear in a document.

Author:

Douglas Johnson, Vassilis Plachouras

Field Summary

protected int

DocumentBlockCountDelta

Fields inherited from class org.terrier.structures.DirectIndex

docIndex

Fields inherited from class org.terrier.structures.BitPostingIndex

fieldCount, file, index, postingConstructor, postingImplementation

Constructor Summary

BlockDirectIndex(Index index, java.lang.String structureName)
Constructs an instance of the class with the given index, using the specified structure name.

BlockDirectIndex(Index index, java.lang.String structureName, java.lang.Class<? extends IterablePosting> postingClass)
Constructs an instance of the class with

Method Summary

int[][]	getTerms(BitIndexPointer pointer) Get the terms for the document at the specified bit index pointer.
int[][]	getTerms(int docid) Returns a five dimensional array containing the term ids and the term frequencies for the given document.

Methods inherited from class org.terrier.structures.DirectIndex

main

Methods inherited from class org.terrier.structures.BitPostingIndex

close, getPostings

Methods inherited from class java.lang.Object

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

Field Detail

DocumentBlockCountDelta

protected int DocumentBlockCountDelta

Constructor Detail

BlockDirectIndex

public BlockDirectIndex(Index index,
                        java.lang.String structureName)
                 throws java.io.IOException

Constructs an instance of the class with the given index, using the specified structure name.

Parameters:

index - The index to be used

structureName - the name of this direct index

Throws:

java.io.IOException

BlockDirectIndex

public BlockDirectIndex(Index index,
                        java.lang.String structureName,
                        java.lang.Class<? extends IterablePosting> postingClass)
                 throws java.io.IOException

Constructs an instance of the class with

Parameters:

index -

structureName -

postingClass -

Throws:

java.io.IOException

Method Detail

getTerms

public int[][] getTerms(int docid)
                 throws java.io.IOException

Returns a five dimensional array containing the term ids and the term frequencies for the given document.

Overrides:

getTerms in class DirectIndex

Parameters:

docid - the id of the document whose terms we are looking for.

Returns:

int[][] a five dimensional array containing the term ids, frequencies, field scores, block frequencies and the containing the block ids.

Throws:

java.io.IOException

getTerms

public int[][] getTerms(BitIndexPointer pointer)
                 throws java.io.IOException

Get the terms for the document at the specified bit index pointer. See getTerms(int docid) for the return specification.

Overrides:

getTerms in class DirectIndex

Throws:

java.io.IOException