001    /*
002     * JBoss, Home of Professional Open Source.
003     * Copyright 2008, Red Hat Middleware LLC, and individual contributors
004     * as indicated by the @author tags. See the copyright.txt file in the
005     * distribution for a full listing of individual contributors. 
006     *
007     * This is free software; you can redistribute it and/or modify it
008     * under the terms of the GNU Lesser General Public License as
009     * published by the Free Software Foundation; either version 2.1 of
010     * the License, or (at your option) any later version.
011     *
012     * This software is distributed in the hope that it will be useful,
013     * but WITHOUT ANY WARRANTY; without even the implied warranty of
014     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
015     * Lesser General Public License for more details.
016     *
017     * You should have received a copy of the GNU Lesser General Public
018     * License along with this software; if not, write to the Free
019     * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
020     * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
021     */
022    package org.jboss.dna.connector.federation.contribution;
023    
024    import java.util.Iterator;
025    import java.util.LinkedList;
026    import java.util.List;
027    import net.jcip.annotations.Immutable;
028    import org.jboss.dna.graph.Location;
029    import org.jboss.dna.graph.properties.DateTime;
030    
031    /**
032     * The contribution of a source to the information for a single federated node.
033     * 
034     * @author Randall Hauch
035     */
036    @Immutable
037    public class MultiChildContribution extends NonEmptyContribution {
038    
039        /**
040         * This is the first version of this class. See the documentation of MergePlan.serialVersionUID.
041         */
042        private static final long serialVersionUID = 1L;
043    
044        private List<Location> children;
045    
046        /**
047         * Create a contribution of children from the source with the supplied name.
048         * 
049         * @param sourceName the name of the source, which may not be null or blank
050         * @param locationInSource the location in the source for this contributed information; may not be null
051         * @param expirationTime the time (in UTC) after which this contribution should be considered expired, or null if there is no
052         *        expiration time
053         * @param children the children from the source; may not be null or empty
054         */
055        public MultiChildContribution( String sourceName,
056                                       Location locationInSource,
057                                       DateTime expirationTime,
058                                       Iterable<Location> children ) {
059            super(sourceName, locationInSource, expirationTime);
060            assert children != null;
061            this.children = new LinkedList<Location>();
062            for (Location child : children) {
063                if (child != null) this.children.add(child);
064            }
065            assert this.children.isEmpty() == false;
066            if (ContributionStatistics.RECORD) ContributionStatistics.record(0, this.children.size());
067        }
068    
069        /**
070         * {@inheritDoc}
071         * 
072         * @see org.jboss.dna.connector.federation.contribution.Contribution#getChildren()
073         */
074        @Override
075        public Iterator<Location> getChildren() {
076            return new ImmutableIterator<Location>(children.iterator());
077        }
078    
079        /**
080         * {@inheritDoc}
081         * 
082         * @see org.jboss.dna.connector.federation.contribution.Contribution#getChildrenCount()
083         */
084        @Override
085        public int getChildrenCount() {
086            return children.size();
087        }
088    }