org.terrier.realtime.memory

Class MemoryIterablePosting

java.lang.Object

org.terrier.structures.postings.IterablePostingImpl

org.terrier.realtime.memory.MemoryIterablePosting

All Implemented Interfaces:

Closeable, AutoCloseable, IterablePosting, Posting

Direct Known Subclasses:

MemoryFieldsIterablePosting

public class MemoryIterablePosting
extends IterablePostingImpl

A postings list implementation held fully in memory.

Since:

4.0

Author:

Richard McCreadie, Stuart Mackie

Field Summary

Fields

Modifier and Type	Field and Description
protected DocumentIndex	doi
protected int	index
protected gnu.trove.TIntArrayList	pl_doc

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

EOL

Constructor Summary

Constructors

Constructor and Description
MemoryIterablePosting(DocumentIndex doi, gnu.trove.TIntArrayList pl_doc, gnu.trove.TIntArrayList pl_freq) Constructor.

Method Summary

Methods

Modifier and Type	Method and Description
WritablePosting	asWritablePosting() Copies this posting to one free of an iterator.
void	close()
boolean	endOfPostings() Status method to see if this posting list iterator has been finished
int	getDocumentLength() Return the length of the document for this posting.
int	getFrequency() Return the frequency of the term in the current document
int	getId() Return the id of the current posting.
int	next() Move this iterator to the next posting.
void	setId(int id) Not implemented.

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

index

protected int index

doi

protected DocumentIndex doi

pl_doc

protected gnu.trove.TIntArrayList pl_doc

Constructor Detail

MemoryIterablePosting

public MemoryIterablePosting(DocumentIndex doi,
                     gnu.trove.TIntArrayList pl_doc,
                     gnu.trove.TIntArrayList pl_freq)

Constructor.

Method Detail

getFrequency

public int getFrequency()

Return the frequency of the term in the current document

Returns:

frequency of posting, in tokens

getDocumentLength

public int getDocumentLength()

Return the length of the document for this posting. Usually uses the DocumentIndex, may do otherwise if document length statistics are in posting list

Returns:

length of the document of the current posting in tokens.

getId

public int getId()

Return the id of the current posting. For the inverted index, this is the docid; for the direct index it corresponds to the term id

Returns:

id of the posting

next

public int next()
         throws IOException

Move this iterator to the next posting.

Returns:

id of next posting, or EOL if end of posting list

Throws:

IOException

endOfPostings

public boolean endOfPostings()

Status method to see if this posting list iterator has been finished

Returns:

true if next() or next(int) would return EOL or have returned EOL.

close

public void close()
           throws IOException

Throws:

IOException

setId

public void setId(int id)

Not implemented.

asWritablePosting

public WritablePosting asWritablePosting()

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

Returns:

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