gate.creole.annic.apache.lucene.index
Class SegmentMerger

java.lang.Object
  gate.creole.annic.apache.lucene.index.SegmentMerger

final class SegmentMerger
extends Object

The SegmentMerger class combines two or more Segments, represented by an IndexReader (add(gate.creole.annic.apache.lucene.index.IndexReader), into a single Segment. After adding the appropriate readers, call the merge method to combine the segments.

If the compoundFile flag is set, then the segments will be merged into a compound file.

See Also:

merge(), add(gate.creole.annic.apache.lucene.index.IndexReader)

Field Summary

private static String[]	COMPOUND_EXTENSIONS
private Directory	directory
private FieldInfos	fieldInfos
private OutputStream	freqOutput
private int	lastSkipDoc
private long	lastSkipFreqPointer
private long	lastSkipProxPointer
private OutputStream	proxOutput
private SegmentMergeQueue	queue
private Vector	readers
private String	segment
private RAMOutputStream	skipBuffer
private int	skipInterval
private TermInfo	termInfo
private TermInfosWriter	termInfosWriter
private boolean	useCompoundFile
private static String[]	VECTOR_EXTENSIONS

Constructor Summary

SegmentMerger(Directory dir, String name, boolean compoundFile)

Method Summary

(package private) void	add(IndexReader reader) Add an IndexReader to the collection of readers that are to be merged
private int	appendPostings(SegmentMergeInfo[] smis, int n) Process postings from multiple segments all positioned on the same term.
private void	bufferSkip(int doc)
(package private) void	closeReaders() close all IndexReaders that have been added.
private void	createCompoundFile()
(package private) int	merge() Merges the readers specified by the add(gate.creole.annic.apache.lucene.index.IndexReader) method into the directory passed to the constructor
private int	mergeFields()
private void	mergeNorms()
private void	mergeTermInfo(SegmentMergeInfo[] smis, int n) Merge one term found in one or more segments.
private void	mergeTermInfos()
private void	mergeTerms()
private void	mergeVectors() Merge the TermVectors from each of the segments into the new one.
private void	resetSkip()
(package private) IndexReader	segmentReader(int i)
private long	writeSkip()

Methods inherited from class java.lang.Object

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

Field Detail

useCompoundFile

private boolean useCompoundFile

directory

private Directory directory

segment

private String segment

readers

private Vector readers

fieldInfos

private FieldInfos fieldInfos

COMPOUND_EXTENSIONS

private static final String[] COMPOUND_EXTENSIONS

VECTOR_EXTENSIONS

private static final String[] VECTOR_EXTENSIONS

freqOutput

private OutputStream freqOutput

proxOutput

private OutputStream proxOutput

termInfosWriter

private TermInfosWriter termInfosWriter

skipInterval

private int skipInterval

queue

private SegmentMergeQueue queue

termInfo

private final TermInfo termInfo

skipBuffer

private RAMOutputStream skipBuffer

lastSkipDoc

private int lastSkipDoc

lastSkipFreqPointer

private long lastSkipFreqPointer

lastSkipProxPointer

private long lastSkipProxPointer

Constructor Detail

SegmentMerger

SegmentMerger(Directory dir,
              String name,
              boolean compoundFile)

Parameters:

dir - The Directory to merge the other segments into

name - The name of the new segment

compoundFile - true if the new segment should use a compoundFile

Method Detail

add

final void add(IndexReader reader)

Add an IndexReader to the collection of readers that are to be merged

Parameters:

reader -

segmentReader

final IndexReader segmentReader(int i)

Parameters:

i - The index of the reader to return

Returns:

The ith reader to be merged

merge

final int merge()
         throws IOException

Merges the readers specified by the add(gate.creole.annic.apache.lucene.index.IndexReader) method into the directory passed to the constructor

Returns:

The number of documents that were merged

Throws:

IOException

closeReaders

final void closeReaders()
                 throws IOException

close all IndexReaders that have been added. Should not be called before merge().

Throws:

IOException

createCompoundFile

private final void createCompoundFile()
                               throws IOException

Throws:

IOException

mergeFields

private final int mergeFields()
                       throws IOException

Returns:

The number of documents in all of the readers

Throws:

IOException

mergeVectors

private final void mergeVectors()
                         throws IOException

Merge the TermVectors from each of the segments into the new one.

Throws:

IOException

mergeTerms

private final void mergeTerms()
                       throws IOException

Throws:

IOException

mergeTermInfos

private final void mergeTermInfos()
                           throws IOException

Throws:

IOException

mergeTermInfo

private final void mergeTermInfo(SegmentMergeInfo[] smis,
                                 int n)
                          throws IOException

Merge one term found in one or more segments. The array smis contains segments that are positioned at the same term. N is the number of cells in the array actually occupied.

Parameters:

smis - array of segments

n - number of cells in the array actually occupied

Throws:

IOException

appendPostings

private final int appendPostings(SegmentMergeInfo[] smis,
                                 int n)
                          throws IOException

Process postings from multiple segments all positioned on the same term. Writes out merged entries into freqOutput and the proxOutput streams.

Parameters:

smis - array of segments

n - number of cells in the array actually occupied

Returns:

number of documents across all segments where this term was found

Throws:

IOException

resetSkip

private void resetSkip()
                throws IOException

Throws:

IOException

bufferSkip

private void bufferSkip(int doc)
                 throws IOException

Throws:

IOException

writeSkip

private long writeSkip()
                throws IOException

Throws:

IOException

mergeNorms

private void mergeNorms()
                 throws IOException

Throws:

IOException