org.apache.lucene.index

Class SegmentInfo

java.lang.Object

org.apache.lucene.index.SegmentInfo

public final class SegmentInfo
extends Object

Information about a segment such as it's name, directory, and files related to the segment.

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

Field Summary

Fields

Modifier and Type	Field and Description
Directory	dir
String	name
static int	NO
static int	YES

Constructor Summary

Constructors

Constructor and Description
SegmentInfo(Directory dir, String version, String name, int docCount, boolean isCompoundFile, Codec codec, Map<String,String> diagnostics, Map<String,String> attributes) Construct a new complete SegmentInfo instance from input.

Method Summary

Methods

Modifier and Type	Method and Description
void	addFile(String file)
void	addFiles(Collection<String> files)
Map<String,String>	attributes()
boolean	equals(Object obj) We consider another SegmentInfo instance equal if it has the same dir and same name.
Set<String>	files()
String	getAttribute(String key) Get a codec attribute value, or null if it does not exist
Codec	getCodec()
Map<String,String>	getDiagnostics()
int	getDocCount()
boolean	getUseCompoundFile() Returns true if this segment is stored as a compound file; else, false.
String	getVersion() Returns the version of the code which wrote the segment.
int	hashCode()
String	putAttribute(String key, String value) Puts a codec attribute value.
void	setCodec(Codec codec) Can only be called once.
void	setFiles(Set<String> files)
void	setVersion(String version) Used by DefaultSegmentInfosReader to upgrade a 3.0 segment to record its version is "3.0".
long	sizeInBytes() Returns total size in bytes of all of files used by this segment.
String	toString()
String	toString(Directory dir, int delCount) Used for debugging.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

NO

public static final int NO

See Also:

Constant Field Values

YES

public static final int YES

See Also:

Constant Field Values

name

public final String name

dir

public final Directory dir

Constructor Detail

SegmentInfo

public SegmentInfo(Directory dir,
           String version,
           String name,
           int docCount,
           boolean isCompoundFile,
           Codec codec,
           Map<String,String> diagnostics,
           Map<String,String> attributes)

Construct a new complete SegmentInfo instance from input.

Note: this is public only to allow access from the codecs package.

Method Detail

getDiagnostics

public Map<String,String> getDiagnostics()

sizeInBytes

public long sizeInBytes()
                 throws IOException

Returns total size in bytes of all of files used by this segment. Note that this will not include any live docs for the segment; to include that use SegmentInfoPerCommit.sizeInBytes() instead.

Throws:

IOException

getUseCompoundFile

public boolean getUseCompoundFile()

Returns true if this segment is stored as a compound file; else, false.

setCodec

public void setCodec(Codec codec)

Can only be called once.

getCodec

public Codec getCodec()

getDocCount

public int getDocCount()

files

public Set<String> files()

toString

public String toString()

Overrides:

toString in class Object

toString

public String toString(Directory dir,
              int delCount)

Used for debugging. Format may suddenly change.

Current format looks like _a(3.1):c45/4, which means the segment's name is _a; it was created with Lucene 3.1 (or '?' if it's unknown); it's using compound file format (would be C if not compound); it has 45 documents; it has 4 deletions (this part is left off when there are no deletions).

equals

public boolean equals(Object obj)

We consider another SegmentInfo instance equal if it has the same dir and same name.

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

setVersion

public void setVersion(String version)

Used by DefaultSegmentInfosReader to upgrade a 3.0 segment to record its version is "3.0". This method can be removed when we're not required to support 3x indexes anymore, e.g. in 5.0.

NOTE: this method is used for internal purposes only - you should not modify the version of a SegmentInfo, or it may result in unexpected exceptions thrown when you attempt to open the index.

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

getVersion

public String getVersion()

Returns the version of the code which wrote the segment.

setFiles

public void setFiles(Set<String> files)

addFiles

public void addFiles(Collection<String> files)

addFile

public void addFile(String file)

getAttribute

public String getAttribute(String key)

Get a codec attribute value, or null if it does not exist

putAttribute

public String putAttribute(String key,
                  String value)

Puts a codec attribute value.

This is a key-value mapping for the field that the codec can use to store additional metadata, and will be available to the codec when reading the segment via getAttribute(String)

If a value already exists for the field, it will be replaced with the new value.

attributes

public Map<String,String> attributes()

Returns:

internal codec attributes map. May be null if no mappings exist.