001 /* 002 * JBoss DNA (http://www.jboss.org/dna) 003 * See the COPYRIGHT.txt file distributed with this work for information 004 * regarding copyright ownership. Some portions may be licensed 005 * to Red Hat, Inc. under one or more contributor license agreements. 006 * See the AUTHORS.txt file in the distribution for a full listing of 007 * individual contributors. 008 * 009 * JBoss DNA is free software. Unless otherwise indicated, all code in JBoss DNA 010 * is licensed to you under the terms of the GNU Lesser General Public License as 011 * published by the Free Software Foundation; either version 2.1 of 012 * the License, or (at your option) any later version. 013 * 014 * JBoss DNA is distributed in the hope that it will be useful, 015 * but WITHOUT ANY WARRANTY; without even the implied warranty of 016 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 017 * Lesser General Public License for more details. 018 * 019 * You should have received a copy of the GNU Lesser General Public 020 * License along with this software; if not, write to the Free 021 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 022 * 02110-1301 USA, or see the FSF site: http://www.fsf.org. 023 */ 024 package org.jboss.dna.connector.federation.contribution; 025 026 import net.jcip.annotations.Immutable; 027 import org.jboss.dna.graph.Location; 028 import org.jboss.dna.graph.property.DateTime; 029 030 /** 031 * A source contribution that is empty. In other words, the source has no contribution to make. 032 * <p> 033 * Note that this is different than an unknown contribution, which may occur when a source is added to a federated repository 034 * after the contributions have already been determined for nodes. In this case, the new source's contribution for a node is not 035 * known and must be determined. 036 * </p> 037 * 038 * @author Randall Hauch 039 */ 040 @Immutable 041 public class EmptyContribution extends Contribution { 042 043 /** 044 * This is the first version of this class. See the documentation of MergePlan.serialVersionUID. 045 */ 046 private static final long serialVersionUID = 1L; 047 048 /** 049 * Create a contribution for the source with the supplied name. 050 * 051 * @param sourceName the name of the source, which may not be null or blank 052 * @param workspaceName the name of the workspace, which may not be null or blank 053 * @param expirationTime the time (in UTC) after which this contribution should be considered expired, or null if there is no 054 * expiration time 055 */ 056 public EmptyContribution( String sourceName, 057 String workspaceName, 058 DateTime expirationTime ) { 059 super(sourceName, workspaceName, expirationTime); 060 if (ContributionStatistics.RECORD) ContributionStatistics.record(0, 0); 061 } 062 063 /** 064 * {@inheritDoc} 065 * 066 * @see org.jboss.dna.connector.federation.contribution.Contribution#getLocationInSource() 067 */ 068 @Override 069 public Location getLocationInSource() { 070 return null; 071 } 072 073 /** 074 * {@inheritDoc} 075 * 076 * @see org.jboss.dna.connector.federation.contribution.Contribution#isEmpty() 077 */ 078 @Override 079 public boolean isEmpty() { 080 return true; 081 } 082 083 /** 084 * {@inheritDoc} 085 */ 086 @Override 087 public boolean equals( Object obj ) { 088 if (obj == this) return true; 089 if (obj instanceof EmptyContribution) { 090 EmptyContribution that = (EmptyContribution)obj; 091 if (!this.getSourceName().equals(that.getSourceName())) return false; 092 if (!this.getWorkspaceName().equals(that.getWorkspaceName())) return false; 093 return true; 094 } 095 return false; 096 } 097 }