org.apache.lucene.store.db

Class DbDirectory

java.lang.Object

org.apache.lucene.store.Directory

org.apache.lucene.store.db.DbDirectory

public class DbDirectory
extends Directory

A DbDirectory is a Berkeley DB 4.3 based implementation of Directory. It uses two Db database handles, one for storing file records and another for storing file data blocks.

Field Summary

Fields

Modifier and Type	Field and Description
protected Db	blocks
protected Db	files
protected int	flags
protected Set	openFiles
protected DbTxn	txn

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

lockFactory

Constructor Summary

Constructors

Constructor and Description
DbDirectory(DbTxn txn, Db files, Db blocks, int flags) Instantiate a DbDirectory.
DbDirectory(Transaction txn, Database files, Database blocks)
DbDirectory(Transaction txn, Database files, Database blocks, int flags)

Method Summary

Methods

Modifier and Type	Method and Description
void	close()
IndexOutput	createOutput(String name)
void	deleteFile(String name)
boolean	fileExists(String name)
long	fileLength(String name)
long	fileModified(String name)
void	flush() Flush the currently open files.
String[]	list()
Lock	makeLock(String name)
IndexInput	openInput(String name)
void	renameFile(String from, String to)
void	setTransaction(DbTxn txn) Once a transaction handle was committed it is no longer valid.
void	setTransaction(Transaction txn) Once a transaction handle was committed it is no longer valid.
void	touchFile(String name)

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

clearLock, copy, ensureOpen, getLockFactory, getLockID, openInput, setLockFactory, sync

Methods inherited from class java.lang.Object

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

Field Detail

openFiles

protected Set openFiles

files

protected Db files

blocks

protected Db blocks

txn

protected DbTxn txn

flags

protected int flags

Constructor Detail

DbDirectory

public DbDirectory(DbTxn txn,
           Db files,
           Db blocks,
           int flags)

Instantiate a DbDirectory. The same threading rules that apply to Berkeley DB handles apply to instances of DbDirectory.

Parameters:

txn - a transaction handle that is going to be used for all db operations done by this instance. This parameter may be null.

files - a db handle to store file records.

blocks - a db handle to store file data blocks.

flags - flags used for db read operations.

DbDirectory

public DbDirectory(Transaction txn,
           Database files,
           Database blocks,
           int flags)

DbDirectory

public DbDirectory(Transaction txn,
           Database files,
           Database blocks)

Method Detail

close

public void close()
           throws IOException

Specified by:

close in class Directory

Throws:

IOException

flush

public void flush()
           throws IOException

Flush the currently open files. After they have been flushed it is safe to commit the transaction without closing this DbDirectory instance first.

Throws:

IOException

See Also:

setTransaction(Transaction)

createOutput

public IndexOutput createOutput(String name)
                         throws IOException

Specified by:

createOutput in class Directory

Throws:

IOException

deleteFile

public void deleteFile(String name)
                throws IOException

Specified by:

deleteFile in class Directory

Throws:

IOException

fileExists

public boolean fileExists(String name)
                   throws IOException

Specified by:

fileExists in class Directory

Throws:

IOException

fileLength

public long fileLength(String name)
                throws IOException

Specified by:

fileLength in class Directory

Throws:

IOException

fileModified

public long fileModified(String name)
                  throws IOException

Specified by:

fileModified in class Directory

Throws:

IOException

list

public String[] list()
              throws IOException

Specified by:

list in class Directory

Throws:

IOException

openInput

public IndexInput openInput(String name)
                     throws IOException

Specified by:

openInput in class Directory

Throws:

IOException

makeLock

public Lock makeLock(String name)

Overrides:

makeLock in class Directory

renameFile

public void renameFile(String from,
              String to)
                throws IOException

Specified by:

renameFile in class Directory

Throws:

IOException

touchFile

public void touchFile(String name)
               throws IOException

Specified by:

touchFile in class Directory

Throws:

IOException

setTransaction

public void setTransaction(Transaction txn)

Once a transaction handle was committed it is no longer valid. In order to continue using this DbDirectory instance after a commit, the transaction handle has to be replaced.

Parameters:

txn - the new transaction handle to use

setTransaction

public void setTransaction(DbTxn txn)

Once a transaction handle was committed it is no longer valid. In order to continue using this DbDirectory instance after a commit, the transaction handle has to be replaced.

Parameters:

txn - the new transaction handle to use