Package org.apache.lucene.codecs

Class CompoundDirectory

java.lang.Object

org.apache.lucene.store.Directory

org.apache.lucene.codecs.CompoundDirectory

All Implemented Interfaces:

Closeable, AutoCloseable

public abstract class CompoundDirectory
extends Directory

A read-only Directory that consists of a view over a compound file.

See Also:

• CompoundFormat

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

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	CompoundDirectory()	Sole constructor.

Method Summary

Modifier and Type	Method	Description
abstract void	checkIntegrity()	Checks consistency of this directory.
final IndexOutput	createOutput(String name, IOContext context)	Creates a new, empty file in the directory and returns an IndexOutput instance for appending data to this file.
final IndexOutput	createTempOutput(String prefix, String suffix, IOContext context)	Creates a new, empty, temporary file in the directory and returns an IndexOutput instance for appending data to this file.
final void	deleteFile(String name)	Not implemented
final Lock	obtainLock(String name)	Acquires and returns a Lock for a file with the given name.
final void	rename(String from, String to)	Not implemented
final void	sync(Collection<String> names)	Ensures that any writes to these files are moved to stable storage (made durable).
final void	syncMetaData()	Ensures that directory metadata, such as recent file renames, are moved to stable storage.

Methods inherited from class org.apache.lucene.store.Directory

close, copyFrom, ensureOpen, fileLength, getPendingDeletions, getTempFileName, listAll, openChecksumInput, openInput, toString

Methods inherited from class java.lang.Object

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

Constructor Details

CompoundDirectory

protected CompoundDirectory()

Sole constructor.

Method Details

checkIntegrity

public abstract void checkIntegrity()
                             throws IOException

Checks consistency of this directory.

Note that this may be costly in terms of I/O, e.g. may involve computing a checksum value against large data files.

Throws:

IOException

deleteFile

public final void deleteFile(String name)

Not implemented

Specified by:

deleteFile in class Directory

Parameters:

name - the name of an existing file.

Throws:

UnsupportedOperationException - always: not supported by CFS

rename

public final void rename(String from,
 String to)

Not implemented

Specified by:

rename in class Directory

Throws:

UnsupportedOperationException - always: not supported by CFS

syncMetaData

public final void syncMetaData()

Description copied from class: Directory

Ensures that directory metadata, such as recent file renames, are moved to stable storage.

Specified by:

syncMetaData in class Directory

See Also:

• Directory.sync(Collection)

createOutput

public final IndexOutput createOutput(String name,
 IOContext context)
                               throws IOException

Description copied from class: Directory

Creates a new, empty file in the directory and returns an IndexOutput instance for appending data to this file.

This method must throw FileAlreadyExistsException if the file already exists.

Specified by:

createOutput in class Directory

Parameters:

name - the name of the file to create.

Throws:

IOException - in case of I/O error

createTempOutput

public final IndexOutput createTempOutput(String prefix,
 String suffix,
 IOContext context)
                                   throws IOException

Description copied from class: Directory

Creates a new, empty, temporary file in the directory and returns an IndexOutput instance for appending data to this file.

The temporary file name (accessible via IndexOutput.getName()) will start with prefix, end with suffix and have a reserved file extension .tmp.

Specified by:

createTempOutput in class Directory

Throws:

IOException

sync

public final void sync(Collection<String> names)

Description copied from class: Directory

Ensures that any writes to these files are moved to stable storage (made durable).

Lucene uses this to properly commit changes to the index, to prevent a machine/OS crash from corrupting the index.

Specified by:

sync in class Directory

See Also:

• Directory.syncMetaData()

obtainLock

public final Lock obtainLock(String name)

Description copied from class: Directory

Acquires and returns a Lock for a file with the given name.

Specified by:

obtainLock in class Directory

Parameters:

name - the name of the lock file