uk.ac.gla.terrier.structures.indexing.singlepass
Class FileRunIterator<K extends PostingInRun>

java.lang.Object
  uk.ac.gla.terrier.structures.indexing.singlepass.RunIterator
      uk.ac.gla.terrier.structures.indexing.singlepass.FileRunIterator<K>

All Implemented Interfaces:

java.util.Iterator<PostingInRun>, Closeable

public class FileRunIterator<K extends PostingInRun>
extends RunIterator

Reads runs of flushed term posting lists by reading them from files.

Since:

2.2

Version:

$Revision: 1.4 $

Author:

Craig Macdonald

Constructor Summary

FileRunIterator(java.lang.String filename, java.lang.String termsFile, int runNo, java.lang.Class<? extends PostingInRun> _postingInRunClass)
Load a new run from files.

Method Summary

void	close() Closes the run files being processed
boolean	hasNext() Are there more posting to process in this run?
PostingInRun	next() Move to the next posting in this run
java.lang.String	readString() Reads the String identifying a term from the underlying stream.
int	readTermFrequency() Reads the term frequency for the current posting, and aligns the stream.

Methods inherited from class uk.ac.gla.terrier.structures.indexing.singlepass.RunIterator

current, getRunNo, remove

Methods inherited from class java.lang.Object

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

Constructor Detail

FileRunIterator

public FileRunIterator(java.lang.String filename,
                       java.lang.String termsFile,
                       int runNo,
                       java.lang.Class<? extends PostingInRun> _postingInRunClass)
                throws java.lang.Exception

Load a new run from files.

Parameters:

filename - the filename of the file containing the posting lists

termsFile - the filename of the file containing the term names

runNo - the number of this run

_postingInRunClass - the class that all postings in this class have

Throws:

java.lang.Exception

Method Detail

close

public void close()

Closes the run files being processed

Specified by:

close in interface Closeable

Overrides:

close in class RunIterator

hasNext

public boolean hasNext()

Are there more posting to process in this run?

Specified by:

hasNext in interface java.util.Iterator<PostingInRun>

Specified by:

hasNext in class RunIterator

next

public PostingInRun next()

Move to the next posting in this run

Specified by:

next in interface java.util.Iterator<PostingInRun>

Specified by:

next in class RunIterator

readTermFrequency

public int readTermFrequency()
                      throws java.io.IOException

Reads the term frequency for the current posting, and aligns the stream.

Returns:

the frequency read.

Throws:

java.io.IOException - if an I/O error occurs.

readString

public java.lang.String readString()
                            throws java.io.IOException

Reads the String identifying a term from the underlying stream.

Returns:

the String with the term.

Throws:

java.io.IOException - if an I/O error occurs.