Paul Holmes-Higgin cefda8c965 Updated header to LGPL
git-svn-id: https://svn.alfresco.com/repos/alfresco-enterprise/alfresco/HEAD/root@18931 c4b6b30b-aa2e-2d43-bbcb-ca4b014f7261
2010-03-01 22:48:39 +00:00

77 lines
3.3 KiB
Java

/*
* Copyright (C) 2005-2010 Alfresco Software Limited.
*
* This file is part of Alfresco
*
* Alfresco is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* Alfresco is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with Alfresco. If not, see <http://www.gnu.org/licenses/>.
*/
package org.alfresco.repo.domain.locks;
import org.alfresco.repo.lock.LockAcquisitionException;
import org.alfresco.service.namespace.QName;
/**
* DAO services for <b>alf_lock</b> and related tables
*
* @author Derek Hulley
* @since 3.2
*/
public interface LockDAO
{
/**
* Aquire a given exclusive lock, assigning it (and any implicitly shared locks) a
* timeout. All shared locks are implicitly taken as well.
* <p>
* A lock can be re-taken if it has expired and if the lock token has not changed
*
* @param lockQName the unique name of the lock to acquire
* @param lockToken the potential lock token (max 36 chars)
* @param timeToLive the time (in milliseconds) that the lock must remain
* @return Returns <tt>true</tt> if the lock was taken,
* otherwise <tt>false</tt>
* @throws LockAcquisitionException on failure
*/
void getLock(QName lockQName, String lockToken, long timeToLive);
/**
* Refresh a held lock. This is successful if the lock in question still exists
* and if the lock token has not changed. Lock expiry does not prevent the lock
* from being refreshed.
*
* @param lockQName the unique name of the lock to update
* @param lockToken the lock token for the lock held
* @param timeToLive the new time to live (in milliseconds)
* @return Returns <tt>true</tt> if the lock was updated,
* otherwise <tt>false</tt>
* @throws LockAcquisitionException on failure
*/
void refreshLock(QName lockQName, String lockToken, long timeToLive);
/**
* Release a lock. The lock token must still apply and all the shared and exclusive
* locks need to still be present. Lock expiration does not prevent this operation
* from succeeding.
* <p>
* Note: Failure to release a lock due to a exception condition is dealt with by
* passing the exception out.
*
* @param lockQName the unique name of the lock to release
* @param lockToken the current lock token
* @return Returns <tt>true</tt> if all the required locks were
* (still) held under the lock token and were
* valid at the time of release, otherwise <tt>false</tt>
*/
void releaseLock(QName lockQName, String lockToken);
}