org.apache.lucene.store
Class RAMDirectory

java.lang.Object
  extended byorg.apache.lucene.store.Directory
      extended byorg.apache.lucene.store.RAMDirectory

public final class RAMDirectory
extends Directory

A memory-resident Directory implementation.

Version:
$Id: RAMDirectory.java,v 1.11 2003/11/18 13:05:13 otis Exp $

Constructor Summary
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
 void close()
          Closes the store to future operations.
 OutputStream createFile(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.
 InputStream openFile(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 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

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
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)
                        throws IOException
Returns the time the named file was last modified.

Specified by:
fileModified in class Directory
Throws:
IOException

touchFile

public void touchFile(String name)
               throws IOException
Set the modified time of an existing file to now.

Specified by:
touchFile in class Directory
Throws:
IOException

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

createFile

public final OutputStream createFile(String name)
Creates a new, empty file in the directory with the given name. Returns a stream writing this file.

Specified by:
createFile in class Directory

openFile

public final InputStream openFile(String name)
Returns a stream reading an existing file.

Specified by:
openFile 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


Copyright © 2000-2003 Apache Software Foundation. All Rights Reserved.