Package org.apache.lucene.index

Class OneMergeWrappingMergePolicy

java.lang.Object

org.apache.lucene.index.MergePolicy

org.apache.lucene.index.FilterMergePolicy

org.apache.lucene.index.OneMergeWrappingMergePolicy

All Implemented Interfaces:

Unwrappable<MergePolicy>

Direct Known Subclasses:

SoftDeletesRetentionMergePolicy

public class OneMergeWrappingMergePolicy
extends FilterMergePolicy

A wrapping merge policy that wraps the MergePolicy.OneMerge objects returned by the wrapped merge policy.

WARNING: This API is experimental and might change in incompatible ways in the next release.

Nested Class Summary

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

MergePolicy.MergeAbortedException, MergePolicy.MergeContext, MergePolicy.MergeException, MergePolicy.MergeSpecification, MergePolicy.OneMerge, MergePolicy.OneMergeProgress

Field Summary

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

in

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

DEFAULT_MAX_CFS_SEGMENT_SIZE, DEFAULT_NO_CFS_RATIO, maxCFSSegmentSize, noCFSRatio

Constructor Summary

Constructors

Constructor	Description
OneMergeWrappingMergePolicy(MergePolicy in, UnaryOperator<MergePolicy.OneMerge> wrapOneMerge)	Constructor

Method Summary

Modifier and Type	Method	Description
MergePolicy.MergeSpecification	findForcedDeletesMerges(SegmentInfos segmentInfos, MergePolicy.MergeContext mergeContext)	Determine what set of merge operations is necessary in order to expunge all deletes from the index.
MergePolicy.MergeSpecification	findForcedMerges(SegmentInfos segmentInfos, int maxSegmentCount, Map<SegmentCommitInfo,Boolean> segmentsToMerge, MergePolicy.MergeContext mergeContext)	Determine what set of merge operations is necessary in order to merge to <= the specified segment count.
MergePolicy.MergeSpecification	findFullFlushMerges(MergeTrigger mergeTrigger, SegmentInfos segmentInfos, MergePolicy.MergeContext mergeContext)	Identifies merges that we want to execute (synchronously) on commit.
MergePolicy.MergeSpecification	findMerges(MergeTrigger mergeTrigger, SegmentInfos segmentInfos, MergePolicy.MergeContext mergeContext)	Determine what set of merge operations are now necessary on the index.

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

getMaxCFSSegmentSizeMB, getNoCFSRatio, keepFullyDeletedSegment, numDeletesToMerge, setMaxCFSSegmentSizeMB, setNoCFSRatio, size, toString, unwrap, useCompoundFile

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

assertDelCount, isMerged, message, segString, verbose

Methods inherited from class java.lang.Object

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

Constructor Details

OneMergeWrappingMergePolicy

public OneMergeWrappingMergePolicy(MergePolicy in,
 UnaryOperator<MergePolicy.OneMerge> wrapOneMerge)

Constructor

Parameters:

in - - the wrapped merge policy

wrapOneMerge - - operator for wrapping OneMerge objects

Method Details

findMerges

public MergePolicy.MergeSpecification findMerges(MergeTrigger mergeTrigger,
 SegmentInfos segmentInfos,
 MergePolicy.MergeContext mergeContext)
                                          throws IOException

Description copied from class: MergePolicy

Determine what set of merge operations are now necessary on the index. IndexWriter calls this whenever there is a change to the segments. This call is always synchronized on the IndexWriter instance so only one thread at a time will call this method.

Overrides:

findMerges in class FilterMergePolicy

Parameters:

mergeTrigger - the event that triggered the merge

segmentInfos - the total set of segments in the index

mergeContext - the IndexWriter to find the merges on

Throws:

IOException

findForcedMerges

public MergePolicy.MergeSpecification findForcedMerges(SegmentInfos segmentInfos,
 int maxSegmentCount,
 Map<SegmentCommitInfo,Boolean> segmentsToMerge,
 MergePolicy.MergeContext mergeContext)
                                                throws IOException

Description copied from class: MergePolicy

Determine what set of merge operations is necessary in order to merge to <= the specified segment count. IndexWriter calls this when its IndexWriter.forceMerge(int) method is called. This call is always synchronized on the IndexWriter instance so only one thread at a time will call this method.

Overrides:

findForcedMerges in class FilterMergePolicy

Parameters:

segmentInfos - the total set of segments in the index

maxSegmentCount - requested maximum number of segments in the index

segmentsToMerge - contains the specific SegmentInfo instances that must be merged away. This may be a subset of all SegmentInfos. If the value is True for a given SegmentInfo, that means this segment was an original segment present in the to-be-merged index; else, it was a segment produced by a cascaded merge.

mergeContext - the MergeContext to find the merges on

Throws:

IOException

findForcedDeletesMerges

public MergePolicy.MergeSpecification findForcedDeletesMerges(SegmentInfos segmentInfos,
 MergePolicy.MergeContext mergeContext)
                                                       throws IOException

Description copied from class: MergePolicy

Determine what set of merge operations is necessary in order to expunge all deletes from the index.

Overrides:

findForcedDeletesMerges in class FilterMergePolicy

Parameters:

segmentInfos - the total set of segments in the index

mergeContext - the MergeContext to find the merges on

Throws:

IOException

findFullFlushMerges

public MergePolicy.MergeSpecification findFullFlushMerges(MergeTrigger mergeTrigger,
 SegmentInfos segmentInfos,
 MergePolicy.MergeContext mergeContext)
                                                   throws IOException

Description copied from class: MergePolicy

Identifies merges that we want to execute (synchronously) on commit. By default, this will do no merging on commit. If you implement this method in your MergePolicy you must also set a non-zero timeout using IndexWriterConfig.setMaxFullFlushMergeWaitMillis(long).

Any merges returned here will make IndexWriter.commit(), IndexWriter.prepareCommit() or IndexWriter.getReader(boolean, boolean) block until the merges complete or until LiveIndexWriterConfig.getMaxFullFlushMergeWaitMillis() has elapsed. This may be used to merge small segments that have just been flushed, reducing the number of segments in the point in time snapshot. If a merge does not complete in the allotted time, it will continue to execute, and eventually finish and apply to future point in time snapshot, but will not be reflected in the current one.

If a MergePolicy.OneMerge in the returned MergePolicy.MergeSpecification includes a segment already included in a registered merge, then IndexWriter.commit() or IndexWriter.prepareCommit() will throw a IllegalStateException. Use MergePolicy.MergeContext.getMergingSegments() to determine which segments are currently registered to merge.

Overrides:

findFullFlushMerges in class FilterMergePolicy

Parameters:

mergeTrigger - the event that triggered the merge (COMMIT or GET_READER).

segmentInfos - the total set of segments in the index (while preparing the commit)

mergeContext - the MergeContext to find the merges on, which should be used to determine which segments are already in a registered merge (see MergePolicy.MergeContext.getMergingSegments()).

Throws:

IOException