/*
* JBoss, Home of Professional Open Source.
* Copyright 2012, Red Hat, Inc., 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.jboss.capedwarf.prospectivesearch;
import org.infinispan.distexec.mapreduce.Collator;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.Set;
/**
* @author <a href="mailto:mluksa@redhat.com">Marko Luksa</a>
*/
class TopicsCollator implements Collator<String, Set<String>, List<String>> {
public List<String> collate(Map<String, Set<String>> reducedResults) {
Set<String> topics = reducedResults.get(TopicsMapper.KEY);
return topics == null ? Collections.<String>emptyList() : new ArrayList<String>(topics);
}
}