/*
* JBoss, Home of Professional Open Source.
* Copyright 2011, Red Hat Middleware LLC, and individual contributors
* as indicated by the @author tags. See the copyright.txt file in the
* distribution for a full listing of individual contributors.
*
* This 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 2.1 of
* the License, or (at your option) any later version.
*
* This software 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 software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.infinispan.query.clustered;
import org.hibernate.search.query.engine.spi.DocumentExtractor;
import org.infinispan.AdvancedCache;
import org.infinispan.query.backend.KeyTransformationHandler;
import org.infinispan.query.clustered.commandworkers.QueryExtractorUtil;
import org.infinispan.query.logging.Log;
import org.infinispan.util.concurrent.ConcurrentMapFactory;
import org.infinispan.util.logging.LogFactory;
import java.util.LinkedList;
import java.util.UUID;
import java.util.concurrent.ConcurrentMap;
/**
* Each node in the cluster has a QueryBox instance. The QueryBox keep the active lazy iterators
* (actually it keeps the DocumentExtractor of the searches) on the cluster, so it can return values
* for the queries in a "lazy" way.
*
* When a DistributedLazyIterator is created, every nodes creates a DocumentExtractor and register
* it in your own QueryBox. So, the LazyIterator can fetch the values in a lazy way.
*
* EVICTION: Currently the QueryBox keeps the last BOX_LIMIT DocumentExtractor used... probably
* there is a better way.
*
* @author Israel Lacerra <israeldl@gmail.com>
* @since 5.1
*/
public class QueryBox {
// <query UUID, ISPNQuery>
private final ConcurrentMap<UUID, DocumentExtractor> queries = ConcurrentMapFactory.makeConcurrentMap();
// queries UUIDs ordered (for eviction)
private final LinkedList<UUID> ageOrderedQueries = new LinkedList<UUID>();
// For eviction. Probably there is a better way...
private static final int BOX_LIMIT = 3000;
// this id will be sent with the responses to rpcs
private final UUID myId = UUID.randomUUID();
// the local cache instance
private AdvancedCache<?, ?> cache;
private static final Log log = LogFactory.getLog(QueryBox.class, Log.class);
private KeyTransformationHandler keyTransformationHandler;
/**
* Get the "docIndex" value on the correct DocumentExtractor
*
* @param queryUuid
* The queryId, so we can get the correct DocumentExtractor
* @param docIndex
* value index in the DocumentExtractor
* @return
*/
public Object getValue(UUID queryUuid, int docIndex) {
touch(queryUuid);
DocumentExtractor extractor = queries.get(queryUuid);
if (extractor == null) {
throw new IllegalStateException("Query not found!");
}
Object key = QueryExtractorUtil.extractKey(extractor, cache, keyTransformationHandler, docIndex);
return cache.get(key);
}
private void touch(UUID id) {
synchronized (ageOrderedQueries) {
ageOrderedQueries.remove(id);
ageOrderedQueries.addFirst(id);
}
}
/**
* Kill the query (DocumentExtractor)
*
* @param id
* The id of the query
*/
public void kill(UUID id) {
DocumentExtractor extractor = queries.remove(id);
ageOrderedQueries.remove(id);
if (extractor != null)
extractor.close();
}
/**
* Register a query (DocumentExtractor), so we can lazily load the results.
*
* @param id
* The id of the query
* @param extractor
* The query
*/
public synchronized void put(UUID id, DocumentExtractor extractor) {
synchronized (ageOrderedQueries) {
if (ageOrderedQueries.size() >= BOX_LIMIT) {
ageOrderedQueries.removeLast();
}
ageOrderedQueries.add(id);
}
queries.put(id, extractor);
}
/**
* Id of this QueryBox
*
* @return
*/
public UUID getMyId() {
return myId;
}
public void setCache(AdvancedCache<?, ?> cache) {
this.cache = cache;
keyTransformationHandler = KeyTransformationHandler.getInstance(cache.getAdvancedCache());
}
}