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.properties.DateTime;
029    import org.jboss.dna.graph.properties.Path;
030    import org.jboss.dna.graph.properties.Path.Segment;
031    
032    /**
033     * The contribution of a source to the information for a single federated node.
034     * 
035     * @author Randall Hauch
036     */
037    @Immutable
038    public class MultiChildContribution extends NonEmptyContribution {
039    
040        /**
041         * This is the first version of this class. See the documentation of MergePlan.serialVersionUID.
042         */
043        private static final long serialVersionUID = 1L;
044    
045        private List<Segment> children;
046    
047        /**
048         * Create a contribution of children from the source with the supplied name.
049         * 
050         * @param sourceName the name of the source, which may not be null or blank
051         * @param pathInSource the path in the source for this contributed information; may not be null
052         * @param expirationTime the time (in UTC) after which this contribution should be considered expired, or null if there is no
053         *        expiration time
054         * @param children the children from the source; may not be null or empty
055         */
056        public MultiChildContribution( String sourceName,
057                                       Path pathInSource,
058                                       DateTime expirationTime,
059                                       Iterable<Segment> children ) {
060            super(sourceName, pathInSource, expirationTime);
061            assert children != null;
062            this.children = new LinkedList<Segment>();
063            for (Segment child : children) {
064                if (child != null) this.children.add(child);
065            }
066            assert this.children.isEmpty() == false;
067            if (ContributionStatistics.RECORD) ContributionStatistics.record(0, this.children.size());
068        }
069    
070        /**
071         * {@inheritDoc}
072         * 
073         * @see org.jboss.dna.connector.federation.contribution.Contribution#getChildren()
074         */
075        @Override
076        public Iterator<Segment> getChildren() {
077            return new ImmutableIterator<Segment>(children.iterator());
078        }
079    
080        /**
081         * {@inheritDoc}
082         * 
083         * @see org.jboss.dna.connector.federation.contribution.Contribution#getChildrenCount()
084         */
085        @Override
086        public int getChildrenCount() {
087            return children.size();
088        }
089    }