Package org.apache.lucene.codecs.lucene90

Class Lucene90SegmentInfoFormat

java.lang.Object

org.apache.lucene.codecs.SegmentInfoFormat

org.apache.lucene.codecs.lucene90.Lucene90SegmentInfoFormat

public class Lucene90SegmentInfoFormat
extends SegmentInfoFormat

Lucene 9.0 Segment info format.

Files:

• .si: Header, SegVersion, SegSize, IsCompoundFile, Diagnostics, Files, Attributes, IndexSort, Footer

Data types:

• Header --> IndexHeader
• SegSize --> Int32
• SegVersion --> String
• SegMinVersion --> String
• Files --> Set<String>
• Diagnostics,Attributes --> Map<String,String>
• IsCompoundFile --> Int8
• IndexSort --> Int32 count, followed by count SortField
• SortField --> String sort class, followed by a per-sort bytestream (see SortFieldProvider.readSortField(DataInput))
• Footer --> CodecFooter

Field Descriptions:

• SegVersion is the code version that created the segment.
• SegMinVersion is the minimum code version that contributed documents to the segment.
• SegSize is the number of documents contained in the segment index.
• IsCompoundFile records whether the segment is written as a compound file or not. If this is -1, the segment is not a compound file. If it is 1, the segment is a compound file.
• The Diagnostics Map is privately written by IndexWriter, as a debugging aid, for each segment it creates. It includes metadata like the current Lucene version, OS, Java version, why the segment was created (merge, flush, addIndexes), etc.
• Files is a list of files referred to by this segment.

See Also:

• SegmentInfos

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

Field Summary

Fields

Modifier and Type	Field	Description
static final String	SI_EXTENSION	File extension used to store SegmentInfo.

Constructor Summary

Constructors

Constructor	Description
Lucene90SegmentInfoFormat()	Sole constructor.

Method Summary

Modifier and Type	Method	Description
SegmentInfo	read(Directory dir, String segment, byte[] segmentID, IOContext context)	Read SegmentInfo data from a directory.
void	write(Directory dir, SegmentInfo si, IOContext ioContext)	Write SegmentInfo data.

Methods inherited from class java.lang.Object

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

Field Details

SI_EXTENSION

public static final String SI_EXTENSION

File extension used to store SegmentInfo.

See Also:

• Constant Field Values

Constructor Details

Lucene90SegmentInfoFormat

public Lucene90SegmentInfoFormat()

Sole constructor.

Method Details

read

public SegmentInfo read(Directory dir,
 String segment,
 byte[] segmentID,
 IOContext context)
                 throws IOException

Description copied from class: SegmentInfoFormat

Read SegmentInfo data from a directory.

Specified by:

read in class SegmentInfoFormat

Parameters:

dir - directory to read from

segment - name of the segment to read

segmentID - expected identifier for the segment

Returns:

infos instance to be populated with data

Throws:

IOException - If an I/O error occurs

write

public void write(Directory dir,
 SegmentInfo si,
 IOContext ioContext)
           throws IOException

Description copied from class: SegmentInfoFormat

Write SegmentInfo data. The codec must add its SegmentInfo filename(s) to info before doing i/o.

Specified by:

write in class SegmentInfoFormat

Throws:

IOException - If an I/O error occurs