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.merge;
023    
024    import java.util.Iterator;
025    import java.util.NoSuchElementException;
026    import net.jcip.annotations.ThreadSafe;
027    import org.jboss.dna.common.util.HashCode;
028    import org.jboss.dna.connector.federation.contribution.Contribution;
029    
030    /**
031     * @author Randall Hauch
032     */
033    @ThreadSafe
034    public class ThreeContributionMergePlan extends MergePlan {
035    
036        private static final long serialVersionUID = 1L;
037        private final Contribution contribution1;
038        private final Contribution contribution2;
039        private final Contribution contribution3;
040    
041        /**
042         * @param contribution1 the first contribution for this merge plan
043         * @param contribution2 the second contribution for this merge plan
044         * @param contribution3 the third contribution for this merge plan
045         */
046        /*package*/ThreeContributionMergePlan( Contribution contribution1,
047                                                Contribution contribution2,
048                                                Contribution contribution3 ) {
049            assert contribution1 != null;
050            assert contribution2 != null;
051            assert contribution3 != null;
052            this.contribution1 = contribution1;
053            this.contribution2 = contribution2;
054            this.contribution3 = contribution3;
055            assert checkEachContributionIsFromDistinctSource();
056        }
057    
058        /**
059         * {@inheritDoc}
060         * 
061         * @see org.jboss.dna.connector.federation.merge.MergePlan#getContributionCount()
062         */
063        @Override
064        public int getContributionCount() {
065            return 3;
066        }
067    
068        /**
069         * {@inheritDoc}
070         * 
071         * @see org.jboss.dna.connector.federation.merge.MergePlan#getContributionFrom(java.lang.String)
072         */
073        @Override
074        public Contribution getContributionFrom( String sourceName ) {
075            if (contribution1.getSourceName().equals(sourceName)) return contribution1;
076            if (contribution2.getSourceName().equals(sourceName)) return contribution2;
077            if (contribution3.getSourceName().equals(sourceName)) return contribution3;
078            return null;
079        }
080    
081        /**
082         * {@inheritDoc}
083         * 
084         * @see java.lang.Iterable#iterator()
085         */
086        public Iterator<Contribution> iterator() {
087            return new Iterator<Contribution>() {
088                private int next = 3;
089    
090                public boolean hasNext() {
091                    return next > 0;
092                }
093    
094                @SuppressWarnings( "synthetic-access" )
095                public Contribution next() {
096                    if (next == 3) {
097                        next = 2;
098                        return contribution1;
099                    }
100                    if (next == 2) {
101                        next = 1;
102                        return contribution2;
103                    }
104                    if (next == 1) {
105                        next = 0;
106                        return contribution3;
107                    }
108                    throw new NoSuchElementException();
109                }
110    
111                public void remove() {
112                    throw new UnsupportedOperationException();
113                }
114            };
115        }
116    
117        /**
118         * {@inheritDoc}
119         * 
120         * @see org.jboss.dna.connector.federation.merge.MergePlan#isSource(java.lang.String)
121         */
122        @Override
123        public boolean isSource( String sourceName ) {
124            if (contribution1.getSourceName().equals(sourceName)) return true;
125            if (contribution2.getSourceName().equals(sourceName)) return true;
126            if (contribution3.getSourceName().equals(sourceName)) return true;
127            return false;
128        }
129    
130        /**
131         * {@inheritDoc}
132         * 
133         * @see java.lang.Object#hashCode()
134         */
135        @Override
136        public int hashCode() {
137            return HashCode.compute(contribution1, contribution2, contribution3);
138        }
139    
140    }