org.apache.lucene.store

Class RAMDirectory

java.lang.Object

org.apache.lucene.store.Directory

org.apache.lucene.store.RAMDirectory

public final class RAMDirectory
extends Directory

A memory-resident Directory implementation.

Version:

$Id: RAMDirectory.java 351779 2005-12-02 17:37:50Z bmesser $

Constructor Summary

Constructors

Constructor and Description
RAMDirectory() Constructs an empty Directory.
RAMDirectory(Directory dir) Creates a new RAMDirectory instance from a different Directory implementation.
RAMDirectory(File dir) Creates a new RAMDirectory instance from the FSDirectory.
RAMDirectory(String dir) Creates a new RAMDirectory instance from the FSDirectory.

Method Summary

Methods

Modifier and Type	Method and Description
void	close() Closes the store to future operations.
IndexOutput	createOutput(String name) Creates a new, empty file in the directory with the given name.
void	deleteFile(String name) Removes an existing file in the directory.
boolean	fileExists(String name) Returns true iff the named file exists in this directory.
long	fileLength(String name) Returns the length in bytes of a file in the directory.
long	fileModified(String name) Returns the time the named file was last modified.
String[]	list() Returns an array of strings, one for each file in the directory.
Lock	makeLock(String name) Construct a Lock.
IndexInput	openInput(String name) Returns a stream reading an existing file.
void	renameFile(String from, String to) Removes an existing file in the directory.
void	touchFile(String name) Set the modified time of an existing file to now.

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

createFile, openFile

Methods inherited from class java.lang.Object

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

Constructor Detail

RAMDirectory

public RAMDirectory()

Constructs an empty Directory.

RAMDirectory

public RAMDirectory(Directory dir)
             throws IOException

Creates a new RAMDirectory instance from a different Directory implementation. This can be used to load a disk-based index into memory.

This should be used only with indices that can fit into memory.

Parameters:

dir - a Directory value

Throws:

IOException - if an error occurs

RAMDirectory

public RAMDirectory(File dir)
             throws IOException

Creates a new RAMDirectory instance from the FSDirectory.

Parameters:

dir - a File specifying the index directory

Throws:

IOException

RAMDirectory

public RAMDirectory(String dir)
             throws IOException

Creates a new RAMDirectory instance from the FSDirectory.

Parameters:

dir - a String specifying the full index directory path

Throws:

IOException

Method Detail

list

public final String[] list()

Returns an array of strings, one for each file in the directory.

Specified by:

list in class Directory

fileExists

public final boolean fileExists(String name)

Returns true iff the named file exists in this directory.

Specified by:

fileExists in class Directory

fileModified

public final long fileModified(String name)

Returns the time the named file was last modified.

Specified by:

fileModified in class Directory

touchFile

public void touchFile(String name)

Set the modified time of an existing file to now.

Specified by:

touchFile in class Directory

fileLength

public final long fileLength(String name)

Returns the length in bytes of a file in the directory.

Specified by:

fileLength in class Directory

deleteFile

public final void deleteFile(String name)

Removes an existing file in the directory.

Specified by:

deleteFile in class Directory

renameFile

public final void renameFile(String from,
              String to)

Removes an existing file in the directory.

Specified by:

renameFile in class Directory

createOutput

public final IndexOutput createOutput(String name)

Creates a new, empty file in the directory with the given name. Returns a stream writing this file.

Overrides:

createOutput in class Directory

openInput

public final IndexInput openInput(String name)

Returns a stream reading an existing file.

Overrides:

openInput in class Directory

makeLock

public final Lock makeLock(String name)

Construct a Lock.

Specified by:

makeLock in class Directory

Parameters:

name - the name of the lock file

close

public final void close()

Closes the store to future operations.

Specified by:

close in class Directory