org.elasticsearch.index.shard

Class ElasticsearchMergePolicy

java.lang.Object

org.apache.lucene.index.MergePolicy

org.elasticsearch.index.shard.ElasticsearchMergePolicy

public final class ElasticsearchMergePolicy
extends org.apache.lucene.index.MergePolicy

A MergePolicy that upgrades segments and can upgrade merges.

It can be useful to use the background merging process to upgrade segments, for example when we perform internal changes that imply different index options or when a user modifies his mapping in non-breaking ways: we could imagine using this merge policy to be able to add doc values to fields after the fact or on the opposite to remove them.

For now, this MergePolicy takes care of moving versions that used to be stored as payloads to numeric doc values.

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.lucene.index.MergePolicy

org.apache.lucene.index.MergePolicy.DocMap, org.apache.lucene.index.MergePolicy.MergeAbortedException, org.apache.lucene.index.MergePolicy.MergeException, org.apache.lucene.index.MergePolicy.MergeSpecification, org.apache.lucene.index.MergePolicy.OneMerge

Field Summary

Fields inherited from class org.apache.lucene.index.MergePolicy

DEFAULT_MAX_CFS_SEGMENT_SIZE, DEFAULT_NO_CFS_RATIO, maxCFSSegmentSize, noCFSRatio

Constructor Summary

Constructors

Constructor and Description
ElasticsearchMergePolicy(org.apache.lucene.index.MergePolicy delegate)

Method Summary

Methods

Modifier and Type	Method and Description
org.apache.lucene.index.MergePolicy.MergeSpecification	findForcedDeletesMerges(org.apache.lucene.index.SegmentInfos segmentInfos, org.apache.lucene.index.IndexWriter writer)
org.apache.lucene.index.MergePolicy.MergeSpecification	findForcedMerges(org.apache.lucene.index.SegmentInfos segmentInfos, int maxSegmentCount, Map<org.apache.lucene.index.SegmentCommitInfo,Boolean> segmentsToMerge, org.apache.lucene.index.IndexWriter writer)
org.apache.lucene.index.MergePolicy.MergeSpecification	findMerges(org.apache.lucene.index.MergeTrigger mergeTrigger, org.apache.lucene.index.SegmentInfos segmentInfos, org.apache.lucene.index.IndexWriter writer)
void	setUpgradeInProgress(boolean upgrade, boolean onlyAncientSegments) When upgrade is true, running a force merge will upgrade any segments written with older versions.
String	toString()
boolean	useCompoundFile(org.apache.lucene.index.SegmentInfos segments, org.apache.lucene.index.SegmentCommitInfo newSegment, org.apache.lucene.index.IndexWriter writer)

Methods inherited from class org.apache.lucene.index.MergePolicy

getMaxCFSSegmentSizeMB, getNoCFSRatio, isMerged, setMaxCFSSegmentSizeMB, setNoCFSRatio, size

Methods inherited from class java.lang.Object

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

Constructor Detail

ElasticsearchMergePolicy

public ElasticsearchMergePolicy(org.apache.lucene.index.MergePolicy delegate)

Parameters:

delegate - the merge policy to wrap

Method Detail

findMerges

public org.apache.lucene.index.MergePolicy.MergeSpecification findMerges(org.apache.lucene.index.MergeTrigger mergeTrigger,
                                                                org.apache.lucene.index.SegmentInfos segmentInfos,
                                                                org.apache.lucene.index.IndexWriter writer)
                                                                  throws IOException

Specified by:

findMerges in class org.apache.lucene.index.MergePolicy

Throws:

IOException

findForcedMerges

public org.apache.lucene.index.MergePolicy.MergeSpecification findForcedMerges(org.apache.lucene.index.SegmentInfos segmentInfos,
                                                                      int maxSegmentCount,
                                                                      Map<org.apache.lucene.index.SegmentCommitInfo,Boolean> segmentsToMerge,
                                                                      org.apache.lucene.index.IndexWriter writer)
                                                                        throws IOException

Specified by:

findForcedMerges in class org.apache.lucene.index.MergePolicy

Throws:

IOException

findForcedDeletesMerges

public org.apache.lucene.index.MergePolicy.MergeSpecification findForcedDeletesMerges(org.apache.lucene.index.SegmentInfos segmentInfos,
                                                                             org.apache.lucene.index.IndexWriter writer)
                                                                               throws IOException

Specified by:

findForcedDeletesMerges in class org.apache.lucene.index.MergePolicy

Throws:

IOException

useCompoundFile

public boolean useCompoundFile(org.apache.lucene.index.SegmentInfos segments,
                      org.apache.lucene.index.SegmentCommitInfo newSegment,
                      org.apache.lucene.index.IndexWriter writer)
                        throws IOException

Overrides:

useCompoundFile in class org.apache.lucene.index.MergePolicy

Throws:

IOException

setUpgradeInProgress

public void setUpgradeInProgress(boolean upgrade,
                        boolean onlyAncientSegments)

When upgrade is true, running a force merge will upgrade any segments written with older versions. This will apply to the next call to IndexWriter.forceMerge(int) that is handled by this MergePolicy, as well as cascading calls made by IndexWriter.

toString

public String toString()

Overrides:

toString in class Object