/*
* Hibernate Search, full-text search for your domain model
*
* License: GNU Lesser General Public License (LGPL), version 2.1 or later
* See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
*/
package org.hibernate.search.backend.impl.lucene;
import org.hibernate.search.util.impl.Executors;
import org.hibernate.search.indexes.impl.PropertiesParseHelper;
import org.hibernate.search.spi.WorkerBuildContext;
import org.hibernate.search.backend.BackendFactory;
import org.hibernate.search.backend.impl.lucene.works.LuceneWorkVisitor;
import org.hibernate.search.exception.ErrorHandler;
import org.hibernate.search.indexes.impl.DirectoryBasedIndexManager;
import org.hibernate.search.util.logging.impl.LoggerFactory;
import org.hibernate.search.util.logging.impl.Log;
import java.util.Properties;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantReadWriteLock;
import java.util.concurrent.locks.ReentrantReadWriteLock.ReadLock;
import java.util.concurrent.locks.ReentrantReadWriteLock.WriteLock;
/**
* Collects all resources needed to apply changes to one index,
* and are reused across several WorkQueues.
*
* @author Sanne Grinovero
*/
public final class LuceneBackendResources {
private static final Log log = LoggerFactory.make();
private final LuceneWorkVisitor visitor;
private final AbstractWorkspaceImpl workspace;
private final ErrorHandler errorHandler;
private final ExecutorService queueingExecutor;
private final ExecutorService workersExecutor;
private final int maxQueueLength;
private final String indexName;
private final ReadLock readLock;
private final WriteLock writeLock;
LuceneBackendResources(WorkerBuildContext context, DirectoryBasedIndexManager indexManager, Properties props, AbstractWorkspaceImpl workspace) {
this.indexName = indexManager.getIndexName();
this.errorHandler = context.getErrorHandler();
this.workspace = workspace;
this.visitor = new LuceneWorkVisitor( workspace );
this.maxQueueLength = PropertiesParseHelper.extractMaxQueueSize( indexName, props );
this.queueingExecutor = Executors.newFixedThreadPool( 1, "Index updates queue processor for index " + indexName, maxQueueLength );
this.workersExecutor = BackendFactory.buildWorkersExecutor( props, indexName );
ReentrantReadWriteLock readWriteLock = new ReentrantReadWriteLock();
readLock = readWriteLock.readLock();
writeLock = readWriteLock.writeLock();
}
private LuceneBackendResources(LuceneBackendResources previous) {
this.indexName = previous.indexName;
this.errorHandler = previous.errorHandler;
this.workspace = previous.workspace;
this.visitor = new LuceneWorkVisitor( workspace );
this.maxQueueLength = previous.maxQueueLength;
this.queueingExecutor = previous.queueingExecutor;
this.workersExecutor = previous.workersExecutor;
this.readLock = previous.readLock;
this.writeLock = previous.writeLock;
}
public ExecutorService getQueueingExecutor() {
return queueingExecutor;
}
public ExecutorService getWorkersExecutor() {
return workersExecutor;
}
public int getMaxQueueLength() {
return maxQueueLength;
}
public String getIndexName() {
return indexName;
}
public LuceneWorkVisitor getVisitor() {
return visitor;
}
public AbstractWorkspaceImpl getWorkspace() {
return workspace;
}
public void shutdown() {
//need to close them in this specific order:
try {
flushCloseExecutor( queueingExecutor );
flushCloseExecutor( workersExecutor );
}
finally {
workspace.shutDownNow();
}
}
private void flushCloseExecutor(ExecutorService executor) {
executor.shutdown();
try {
executor.awaitTermination( Long.MAX_VALUE, TimeUnit.SECONDS );
}
catch (InterruptedException e) {
log.interruptedWhileWaitingForIndexActivity( e );
Thread.currentThread().interrupt();
}
if ( ! executor.isTerminated() ) {
log.unableToShutdownAsynchronousIndexingByTimeout( indexName );
}
}
public ErrorHandler getErrorHandler() {
return errorHandler;
}
public Lock getParallelModificationLock() {
return readLock;
}
public Lock getExclusiveModificationLock() {
return writeLock;
}
/**
* Creates a replacement for this same LuceneBackendResources:
* reuses the existing locks and executors (which can't be reconfigured on the fly),
* reuses the same Workspace and ErrorHandler, but will use a new LuceneWorkVisitor.
* The LuceneWorkVisitor contains the strategies we use to apply update operations on the index,
* and we might need to change them after the backend is started.
*
* @return the new LuceneBackendResources to replace this one.
*/
public LuceneBackendResources onTheFlyRebuild() {
return new LuceneBackendResources( this );
}
}