/*
* Hibernate, Relational Persistence for Idiomatic Java
*
* Copyright (c) 2010, Red Hat, Inc. and/or its affiliates or third-party contributors as
* indicated by the @author tags or express copyright attribution
* statements applied by the authors. All third-party contributions are
* distributed under license by Red Hat, Inc.
*
* This copyrighted material is made available to anyone wishing to use, modify,
* copy, or redistribute it subject to the terms and conditions of the GNU
* Lesser General Public License, as published by the Free Software Foundation.
*
* This program 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 this distribution; if not, write to:
* Free Software Foundation, Inc.
* 51 Franklin Street, Fifth Floor
* Boston, MA 02110-1301 USA
*/
package org.hibernate.search.backend;
import java.util.List;
import org.slf4j.Logger;
import org.hibernate.annotations.common.AssertionFailure;
import org.hibernate.search.engine.SearchFactoryImplementor;
import org.hibernate.search.engine.WorkPlan;
import org.hibernate.search.util.LoggerFactory;
/**
* @author Emmanuel Bernard
* @author Sanne Grinovero
*/
public class WorkQueue {
private static final Logger log = LoggerFactory.make();
private WorkPlan plan;
private List<LuceneWork> sealedQueue;
//flag indicating if the sealed data has been provided meaning that it should no longer be modified
private boolean usedSealedData;
//flag indicating if data has been sealed and not modified since
private boolean sealedAndUnchanged;
private final SearchFactoryImplementor searchFactoryImplementor;
public boolean isSealedAndUnchanged() {
return sealedAndUnchanged;
}
public WorkQueue(SearchFactoryImplementor searchFactoryImplementor) {
this.searchFactoryImplementor = searchFactoryImplementor;
this.plan = new WorkPlan( searchFactoryImplementor );
}
public WorkQueue(SearchFactoryImplementor searchFactoryImplementor, WorkPlan plan) {
this.searchFactoryImplementor = searchFactoryImplementor;
this.plan = plan;
}
public void add(Work work) {
if ( usedSealedData ) {
//something is wrong fail with exception
throw new AssertionFailure( "Attempting to add a work in a used sealed queue" );
}
this.sealedAndUnchanged = false;
plan.addWork( work );
}
public WorkQueue splitQueue() {
if ( log.isTraceEnabled() ) {
log.trace( "Splitting workqueue with {} works", plan.size() );
}
WorkQueue subQueue = new WorkQueue( searchFactoryImplementor, plan );
this.plan = new WorkPlan( searchFactoryImplementor );
this.sealedAndUnchanged = false;
return subQueue;
}
public List<LuceneWork> getSealedQueue() {
if ( sealedQueue == null ) throw new AssertionFailure("Access a Sealed WorkQueue which has not been sealed");
this.sealedAndUnchanged = false;
return sealedQueue;
}
private void setSealedQueue(List<LuceneWork> sealedQueue) {
//invalidate the working queue for serializability
/*
* FIXME workaround for flush phase done later
*
* Due to sometimes flush applied after some beforeCompletion phase
* we cannot safely seal the queue, keep it opened as a temporary measure.
* This is not the proper fix unfortunately as we don't optimize the whole work queue but rather two subsets
*
* when the flush ordering is fixed, add the following line
* queue = Collections.EMPTY_LIST;
*/
this.sealedAndUnchanged = true;
this.sealedQueue = sealedQueue;
}
public void clear() {
if ( log.isTraceEnabled() ) {
log.trace( "Clearing current workqueue" );
}
plan.clear();
this.sealedAndUnchanged = false;
if ( sealedQueue != null )
sealedQueue.clear();
}
/**
* Returns an estimate of the to be performed operations
* @see WorkPlan#size()
* @return the approximate size
*/
public int size() {
return plan.size();
}
/**
* Compiles the work collected so far in an optimal execution plan,
* storing the list of lucene operations to be performed in the sealedQueue.
*/
public void prepareWorkPlan() {
if ( ! sealedAndUnchanged ) {
plan.processContainedInAndPrepareExecution();
List<LuceneWork> luceneWorkPlan = plan.getPlannedLuceneWork();
setSealedQueue( luceneWorkPlan );
}
}
}