/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.jena.tdb.store.bulkloader;
import java.util.concurrent.Semaphore ;
import org.apache.jena.atlas.lib.Timer ;
import org.apache.jena.tdb.store.tupletable.TupleIndex ;
public class BuilderSecondaryIndexesParallel implements BuilderSecondaryIndexes
{
private LoadMonitor monitor ;
public BuilderSecondaryIndexesParallel(LoadMonitor monitor) { this.monitor = monitor ; }
@Override
public void createSecondaryIndexes(TupleIndex primaryIndex ,
TupleIndex[] secondaryIndexes)
{
monitor.print("** Parallel index building") ;
Timer timer = new Timer() ;
timer.startTimer() ;
int semaCount = 0 ;
Semaphore sema = new Semaphore(0) ;
for ( TupleIndex index : secondaryIndexes )
{
if ( index != null )
{
Runnable builder = setup(sema, primaryIndex, index, index.getMapping()) ;
new Thread(builder).start() ;
semaCount++ ;
}
}
try { sema.acquire(semaCount) ; } catch (InterruptedException ex) { ex.printStackTrace(); }
long time = timer.readTimer() ;
timer.endTimer() ;
monitor.print("Time for parallel indexing: %.2fs\n", time/1000.0) ;
}
private Runnable setup(final Semaphore sema, final TupleIndex srcIndex, final TupleIndex destIndex, final String label)
{
Runnable builder = new Runnable(){
@Override
public void run()
{
LoaderNodeTupleTable.copyIndex(srcIndex.all(), new TupleIndex[]{destIndex}, label, monitor) ;
sema.release() ;
}} ;
return builder ;
}
}