Package org.terrier.realtime.memory

Class MemoryDirectIndex

java.lang.Object

org.terrier.realtime.memory.MemoryDirectIndex

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable, PostingIndex<MemoryPointer>

Direct Known Subclasses:

MemoryFieldsDirectIndex

public class MemoryDirectIndex
extends java.lang.Object
implements PostingIndex<MemoryPointer>

This is a DirectIndex structure that is held fully in memory, it is based upon the MemoryInverted class. It does not currently support blocks or fields. In v5.2 it was updated to change the way that termids and frequencies were stored, such that we can generate an ordered list of termids. This means that it will take more memory (+50%) and

Since:

4.0

Author:

Richard McCreadie

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
protected class	MemoryDirectIndex.DirectIterator	Direct index iterator.
class	MemoryDirectIndex.DocumentPostingList

Field Summary

Fields

Modifier and Type	Field	Description
protected DocumentIndex	doi
protected gnu.trove.TIntObjectHashMap<MemoryDirectIndex.DocumentPostingList>	postings

Constructor Summary

Constructors

Constructor	Description
MemoryDirectIndex(DocumentIndex doi)	Constructor.

Method Summary

Modifier and Type	Method	Description
void	add(int ptr, int termid, int freq)	Add posting to direct file.
void	close()
IterablePosting	getPostings(int pointer)
IterablePosting	getPostings(Pointer pointer)	Returns the posting iterator given a pointer.
PostingIndexInputStream	iterator()	Return an iterator over the inverted file.

Methods inherited from class java.lang.Object

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

Field Detail

doi

protected DocumentIndex doi

postings

protected gnu.trove.TIntObjectHashMap<MemoryDirectIndex.DocumentPostingList> postings

Constructor Detail

MemoryDirectIndex

public MemoryDirectIndex(DocumentIndex doi)

Constructor.

Method Detail

add

public void add(int ptr,
                int termid,
                int freq)

Add posting to direct file.

getPostings

public IterablePosting getPostings(Pointer pointer)
                            throws java.io.IOException

Description copied from interface: PostingIndex

Returns the posting iterator given a pointer.

Specified by:

getPostings in interface PostingIndex<MemoryPointer>

Returns:

the posting iterator given a pointer.

Throws:

java.io.IOException

getPostings

public IterablePosting getPostings(int pointer)
                            throws java.io.IOException

Throws:

java.io.IOException

close

public void close()
           throws java.io.IOException

Specified by:

close in interface java.lang.AutoCloseable

Specified by:

close in interface java.io.Closeable

Throws:

java.io.IOException

iterator

public PostingIndexInputStream iterator()

Return an iterator over the inverted file.