Package org.apache.lucene.index

# Interface MergePolicy.MergeContext

All Known Implementing Classes:
  `IndexWriter`

Enclosing class:
  `MergePolicy`

public static interface MergePolicy.MergeContext
This interface represents the current context of the merge selection process. It allows to access real-time information like the currently merging segments or how many deletes a segment would claim back if merged. This context might be stateful and change during the execution of a merge policy's selection processes.

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

## Method Summary

Modifier and Type
Method
Description
`InfoStream`
`getInfoStream()`
Returns the info stream that can be used to log messages
`Set<SegmentCommitInfo>`
`getMergingSegments()`
Returns an unmodifiable set of segments that are currently merging.
`int`
`numDeletedDocs(SegmentCommitInfo info)`
Returns the number of deleted documents in the given segments.
`int`
`numDeletesToMerge(SegmentCommitInfo info)`
Returns the number of deletes a merge would claim back if the given segment is merged.

## Method Details

### numDeletesToMerge

int numDeletesToMerge(SegmentCommitInfo info) throws IOException
Returns the number of deletes a merge would claim back if the given segment is merged.

Parameters:
  `info` - the segment to get the number of deletes for
Throws:
  `IOException`
See Also:
  - `MergePolicy.numDeletesToMerge(SegmentCommitInfo, int, org.apache.lucene.util.IOSupplier)`

### numDeletedDocs

int numDeletedDocs(SegmentCommitInfo info)
Returns the number of deleted documents in the given segments.

### getInfoStream

InfoStream getInfoStream()
Returns the info stream that can be used to log messages

### getMergingSegments

Set<SegmentCommitInfo> getMergingSegments()
Returns an unmodifiable set of segments that are currently merging.