Class IndexFileNames

This class contains useful constants representing filenames and extensions used by lucene, as well as convenience methods for querying whether a file name matches an extension (MatchesExtension(string, string)), as well as generating file names from a segment name, generation and extension (FileNameFromGeneration(string, string, long), SegmentFileName(string, string, string)).

NOTE: extensions used by codecs are not listed here. You must interact with the Codec directly.

Note

This API is for internal purposes only and might change in incompatible ways in the next release.

Inheritance

object

IndexFileNames

Inherited Members

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.ReferenceEquals(object, object)

object.ToString()

Namespace: Lucene.Net.Index

Assembly: Lucene.Net.dll

Syntax

public sealed class IndexFileNames

Fields

CODEC_FILE_PATTERN

All files created by codecs much match this pattern (checked in SegmentInfo).

Declaration

public static readonly Regex CODEC_FILE_PATTERN

Field Value

Type	Description
Regex

COMPOUND_FILE_ENTRIES_EXTENSION

Extension of compound file entries

Declaration

public static readonly string COMPOUND_FILE_ENTRIES_EXTENSION

Field Value

Type	Description
string

COMPOUND_FILE_EXTENSION

Extension of compound file

Declaration

public static readonly string COMPOUND_FILE_EXTENSION

Field Value

Type	Description
string

GEN_EXTENSION

Extension of gen file

Declaration

public static readonly string GEN_EXTENSION

Field Value

Type	Description
string

INDEX_EXTENSIONS

This array contains all filename extensions used by Lucene's index files, with one exception, namely the extension made up from .s + a number. Also note that Lucene's segments_N files do not have any filename extension.

Declaration

public static readonly string[] INDEX_EXTENSIONS

Field Value

Type	Description
string[]

SEGMENTS

Name of the index segment file

Declaration

public static readonly string SEGMENTS

Field Value

Type	Description
string

SEGMENTS_GEN

Name of the generation reference file name

Declaration

public static readonly string SEGMENTS_GEN

Field Value

Type	Description
string

Methods

FileNameFromGeneration(string, string, long)

Computes the full file name from base, extension and generation. If the generation is -1, the file name is null. If it's 0, the file name is <base>.<ext>. If it's > 0, the file name is <base>_<gen>.<ext>.

NOTE: .<ext> is added to the name only if ext is not an empty string.

Declaration

public static string FileNameFromGeneration(string @base, string ext, long gen)

Parameters

Type	Name	Description
string	base	main part of the file name
string	ext	extension of the filename
long	gen	generation

Returns

Type	Description
string

GetExtension(string)

Return the extension (anything after the first '.'), or null if there is no '.' in the file name.

Declaration

public static string GetExtension(string filename)

Parameters

Type	Name	Description
string	filename

Returns

Type	Description
string

MatchesExtension(string, string)

Returns true if the given filename ends with the given extension. One should provide a pure extension, without '.'.

Declaration

public static bool MatchesExtension(string filename, string ext)

Parameters

Type	Name	Description
string	filename
string	ext

Returns

Type	Description
bool

ParseSegmentName(string)

Parses the segment name out of the given file name.

Declaration

public static string ParseSegmentName(string filename)

Parameters

Type	Name	Description
string	filename

Returns

Type	Description
string	the segment name only, or filename if it does not contain a '.' and '_'.

SegmentFileName(string, string, string)

Returns a file name that includes the given segment name, your own custom name and extension. The format of the filename is: <segmentName>(_<name>)(.<ext>).

NOTE: .<ext> is added to the result file name only if

ext

is not empty.

NOTE: _<segmentSuffix> is added to the result file name only if it's not the empty string

NOTE: all custom files should be named using this method, or otherwise some structures may fail to handle them properly (such as if they are added to compound files).

Declaration

public static string SegmentFileName(string segmentName, string segmentSuffix, string ext)

Parameters

Type	Name	Description
string	segmentName
string	segmentSuffix
string	ext

Returns

Type	Description
string

StripExtension(string)

Removes the extension (anything after the first '.'), otherwise returns the original filename.

Declaration

public static string StripExtension(string filename)

Parameters

Type	Name	Description
string	filename

Returns

Type	Description
string

StripSegmentName(string)

Strips the segment name out of the given file name. If you used SegmentFileName(string, string, string) or FileNameFromGeneration(string, string, long) to create your files, then this method simply removes whatever comes before the first '.', or the second '_' (excluding both).

Declaration

public static string StripSegmentName(string filename)

Parameters

Type	Name	Description
string	filename

Returns

Type	Description
string	the filename with the segment name removed, or the given filename if it does not contain a '.' and '_'.