org.terrier.structures.indexing
Class BlockLexiconMap

java.lang.Object
  org.terrier.structures.indexing.LexiconMap
      org.terrier.structures.indexing.BlockLexiconMap

Direct Known Subclasses:

BlockFieldLexiconMap

public class BlockLexiconMap
extends LexiconMap

LexiconMap implementation that also keeps track of the number of blocks that a term occurrs in. This is useful for sizing the block inverted index

Field Summary

protected gnu.trove.TObjectIntHashMap<java.lang.String>	blockFreqs Mapping term to blocks
protected long	numberOfBlocks Total number of blocks in this index
protected static byte	zerob
protected static long	zerol

Fields inherited from class org.terrier.structures.indexing.LexiconMap

BUNDLE_AVG_UNIQUE_TERMS, nts, numberOfNodes, numberOfPointers, tfs

Constructor Summary

BlockLexiconMap()

Method Summary

void	clear() Clear the lexicon map
void	insert(DocumentPostingList _doc) Inserts all the terms from a document posting into the lexicon map
void	insert(java.lang.String term, int tf, int blockfreq) Inserts a new term in the lexicon map.
void	storeToStream(LexiconOutputStream<java.lang.String> lexiconStream) Stores the lexicon map to a lexicon stream as a sequence of entries.

Methods inherited from class org.terrier.structures.indexing.LexiconMap

getNumberOfNodes, getNumberOfPointers, insert

Methods inherited from class java.lang.Object

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

Field Detail

zerob

protected static final byte zerob

See Also:

Constant Field Values

zerol

protected static final long zerol

See Also:

Constant Field Values

numberOfBlocks

protected long numberOfBlocks

Total number of blocks in this index

blockFreqs

protected final gnu.trove.TObjectIntHashMap<java.lang.String> blockFreqs

Mapping term to blocks

Constructor Detail

BlockLexiconMap

public BlockLexiconMap()

Method Detail

insert

public void insert(java.lang.String term,
                   int tf,
                   int blockfreq)

Inserts a new term in the lexicon map.

Parameters:

term - The term to be inserted.

tf - The id of the term.

clear

public void clear()

Clear the lexicon map

Overrides:

clear in class LexiconMap

insert

public void insert(DocumentPostingList _doc)

Inserts all the terms from a document posting into the lexicon map

Overrides:

insert in class LexiconMap

Parameters:

_doc - The postinglist for that document - must be a instance of BlockDocumentPostingList.

storeToStream

public void storeToStream(LexiconOutputStream<java.lang.String> lexiconStream)
                   throws java.io.IOException

Stores the lexicon map to a lexicon stream as a sequence of entries.

Overrides:

storeToStream in class LexiconMap

Parameters:

lexiconStream - The lexicon output stream to store to.

Throws:

java.io.IOException