org.apache.lucene.store.jdbc.lock
Class SelectForUpdateLock

java.lang.Object
  org.apache.lucene.store.Lock
      org.apache.lucene.store.jdbc.lock.SelectForUpdateLock

All Implemented Interfaces:

JdbcLock

public class SelectForUpdateLock
extends Lock
implements JdbcLock

A lock based on select...for update.

Note, that not all databases support select ... for update, if the database (dialect) does not support it, a exception will be thrown (see Dialect.supportsForUpdate() .

Also note, that when using select for update locking, when the database is created, the commit and write locks will be created and the select for update will be performed on them. If one wishes to switch to PhantomReadLock, they must be manually deleted.

The lock is released when the transaction is committed, and not when the release method is called.

Author:

kimchy

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.lucene.store.Lock

Lock.With

Field Summary

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

failureReason, LOCK_OBTAIN_WAIT_FOREVER, LOCK_POLL_INTERVAL

Constructor Summary

SelectForUpdateLock()

Method Summary

void	configure(JdbcDirectory jdbcDirectory, String name) Configures the lock.
void	initializeDatabase(JdbcDirectory jdbcDirectory) Called without configure.
boolean	isLocked()
boolean	obtain()
void	release()
String	toString()

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

obtain

Methods inherited from class java.lang.Object

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

Constructor Detail

SelectForUpdateLock

public SelectForUpdateLock()

Method Detail

configure

public void configure(JdbcDirectory jdbcDirectory,
                      String name)
               throws IOException

Description copied from interface: JdbcLock

Configures the lock. Called just after the lock is instantiated.

Specified by:

configure in interface JdbcLock

Parameters:

jdbcDirectory - The directory using the lock

name - The name of the lock

Throws:

IOException

initializeDatabase

public void initializeDatabase(JdbcDirectory jdbcDirectory)
                        throws IOException

Description copied from interface: JdbcLock

Called without configure. Should initialize a creates database.

Specified by:

initializeDatabase in interface JdbcLock

Parameters:

jdbcDirectory - The directory owning the lock

Throws:

IOException

obtain

public boolean obtain()

Specified by:

obtain in class Lock

release

public void release()

Specified by:

release in class Lock

isLocked

public boolean isLocked()

Specified by:

isLocked in class Lock

toString

public String toString()

Overrides:

toString in class Object