gate.creole.annic.apache.lucene.store
Class FSDirectory

java.lang.Object
  extended by gate.creole.annic.apache.lucene.store.Directory
      extended by gate.creole.annic.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 String LOCK_DIR
          Directory specified by gate.creole.annic.apache.lucene.lockdir or java.io.tmpdir system property
 
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 a file with the given name exists.
 long fileLength(String name)
          Returns the length in bytes of a file in the directory.
static long fileModified(File directory, String name)
          Returns the time the named file was last modified.
 long fileModified(String name)
          Returns the time the named file was last modified.
static FSDirectory getDirectory(File file, boolean create)
          Returns the directory instance for the named location.
static FSDirectory getDirectory(String path, boolean create)
          Returns the directory instance for the named location.
 File getFile()
           
 String[] list()
          Returns an array of strings, one for each file in the directory.
 Lock makeLock(String name)
          Constructs a Lock with the specified name.
 InputStream openFile(String name)
          Returns a stream reading an existing file.
 void renameFile(String from, String to)
          Renames an existing file in the directory.
 String toString()
          For debug output.
 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, wait, wait, wait
 

Field Detail

LOCK_DIR

public static final String LOCK_DIR
Directory specified by gate.creole.annic.apache.lucene.lockdir or java.io.tmpdir system property

Method Detail

getDirectory

public static FSDirectory getDirectory(String path,
                                       boolean create)
                                throws 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:
IOException

getDirectory

public static FSDirectory getDirectory(File file,
                                       boolean create)
                                throws 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:
IOException

list

public final String[] list()
                    throws IOException
Returns an array of strings, one for each file in the directory.

Specified by:
list in class Directory
Throws:
IOException

fileExists

public final boolean fileExists(String name)
                         throws IOException
Returns true iff a file with the given name exists.

Specified by:
fileExists in class Directory
Throws:
IOException

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

fileModified

public static final long fileModified(File directory,
                                      String name)
                               throws IOException
Returns the time the named file was last modified.

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)
                      throws IOException
Returns the length in bytes of a file in the directory.

Specified by:
fileLength in class Directory
Throws:
IOException

deleteFile

public final void deleteFile(String name)
                      throws IOException
Removes an existing file in the directory.

Specified by:
deleteFile in class Directory
Throws:
IOException

renameFile

public final void renameFile(String from,
                             String to)
                      throws IOException
Renames an existing file in the directory.

Specified by:
renameFile in class Directory
Throws:
IOException

createFile

public final OutputStream createFile(String name)
                              throws 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:
IOException

openFile

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

Specified by:
openFile in class Directory
Throws:
IOException

makeLock

public final Lock makeLock(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 IOException
Closes the store to future operations.

Specified by:
close in class Directory
Throws:
IOException

getFile

public File getFile()

toString

public String toString()
For debug output.

Overrides:
toString in class Object