org.apache.lucene.store
Class FSDirectory

java.lang.Object
  org.apache.lucene.store.Directory
      org.apache.lucene.store.FSDirectory

public final class FSDirectory

extends Directory

Straightforward implementation of Directory as a directory of files.

If the system property 'disableLuceneLocks' has the String value of "true", lock creation will be disabled.

Author:

Doug Cutting

See Also:

Directory

Field Summary

static java.lang.String

LOCK_DIR Directory specified by org.apache.lucene.lockdir or java.io.tmpdir system property

Method Summary

void	close() Closes the store to future operations.
OutputStream	createFile(java.lang.String name) Creates a new, empty file in the directory with the given name.
void	deleteFile(java.lang.String name) Removes an existing file in the directory.
boolean	fileExists(java.lang.String name) Returns true iff a file with the given name exists.
long	fileLength(java.lang.String name) Returns the length in bytes of a file in the directory.
static long	fileModified(java.io.File directory, java.lang.String name) Returns the time the named file was last modified.
long	fileModified(java.lang.String name) Returns the time the named file was last modified.
static FSDirectory	getDirectory(java.io.File file, boolean create) Returns the directory instance for the named location.
static FSDirectory	getDirectory(java.lang.String path, boolean create) Returns the directory instance for the named location.
java.io.File	getFile()
java.lang.String[]	list() Returns an array of strings, one for each file in the directory.
Lock	makeLock(java.lang.String name) Constructs a Lock with the specified name.
InputStream	openFile(java.lang.String name) Returns a stream reading an existing file.
void	renameFile(java.lang.String from, java.lang.String to) Renames an existing file in the directory.
java.lang.String	toString() For debug output.
void	touchFile(java.lang.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, wait, wait, wait

Field Detail

LOCK_DIR

public static final java.lang.String LOCK_DIR

Directory specified by org.apache.lucene.lockdir or java.io.tmpdir system property

Method Detail

getDirectory

public static FSDirectory getDirectory(java.lang.String path,
                                       boolean create)
                                throws java.io.IOException

Returns the directory instance for the named location.

Directories are cached, so that, for a given canonical path, the same FSDirectory instance will always be returned. This permits synchronization on directories.

Parameters:

path - the path to the directory.

create - if true, create, or erase any existing contents.

Returns:

the FSDirectory for the named file.

Throws:

java.io.IOException

getDirectory

public static FSDirectory getDirectory(java.io.File file,
                                       boolean create)
                                throws java.io.IOException

Returns the directory instance for the named location.

Directories are cached, so that, for a given canonical path, the same FSDirectory instance will always be returned. This permits synchronization on directories.

Parameters:

file - the path to the directory.

create - if true, create, or erase any existing contents.

Returns:

the FSDirectory for the named file.

Throws:

java.io.IOException

list

public final java.lang.String[] list()
                              throws java.io.IOException

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

Specified by:

list in class Directory

Throws:

java.io.IOException

fileExists

public final boolean fileExists(java.lang.String name)
                         throws java.io.IOException

Returns true iff a file with the given name exists.

Specified by:

fileExists in class Directory

Throws:

java.io.IOException

fileModified

public final long fileModified(java.lang.String name)
                        throws java.io.IOException

Returns the time the named file was last modified.

Specified by:

fileModified in class Directory

Throws:

java.io.IOException

fileModified

public static final long fileModified(java.io.File directory,
                                      java.lang.String name)
                               throws java.io.IOException

Returns the time the named file was last modified.

Throws:

java.io.IOException

touchFile

public void touchFile(java.lang.String name)
               throws java.io.IOException

Set the modified time of an existing file to now.

Specified by:

touchFile in class Directory

Throws:

java.io.IOException

fileLength

public final long fileLength(java.lang.String name)
                      throws java.io.IOException

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

Specified by:

fileLength in class Directory

Throws:

java.io.IOException

deleteFile

public final void deleteFile(java.lang.String name)
                      throws java.io.IOException

Removes an existing file in the directory.

Specified by:

deleteFile in class Directory

Throws:

java.io.IOException

renameFile

public final void renameFile(java.lang.String from,
                             java.lang.String to)
                      throws java.io.IOException

Renames an existing file in the directory.

Specified by:

renameFile in class Directory

Throws:

java.io.IOException

createFile

public final OutputStream createFile(java.lang.String name)
                              throws java.io.IOException

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

Specified by:

createFile in class Directory

Throws:

java.io.IOException

openFile

public final InputStream openFile(java.lang.String name)
                           throws java.io.IOException

Returns a stream reading an existing file.

Specified by:

openFile in class Directory

Throws:

java.io.IOException

makeLock

public final Lock makeLock(java.lang.String name)

Constructs a Lock with the specified name. Locks are implemented with File.createNewFile().

In JDK 1.1 or if system property disableLuceneLocks is the string "true", locks are disabled. Assigning this property any other string will not prevent creation of lock files. This is useful for using Lucene on read-only medium, such as CD-ROM.

Specified by:

makeLock in class Directory

Parameters:

name - the name of the lock file

Returns:

an instance of Lock holding the lock

close

public final void close()
                 throws java.io.IOException

Closes the store to future operations.

Specified by:

close in class Directory

Throws:

java.io.IOException

getFile

public java.io.File getFile()

toString

public java.lang.String toString()

For debug output.