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.graph.request;
025
026 import org.jboss.dna.common.util.CheckArg;
027 import org.jboss.dna.common.util.HashCode;
028 import org.jboss.dna.graph.GraphI18n;
029 import org.jboss.dna.graph.Location;
030
031 /**
032 * Instruction to verify the existance of a node at the specified location. This request also returns the actual location.
033 *
034 * @author Randall Hauch
035 */
036 public class VerifyNodeExistsRequest extends CacheableRequest {
037
038 private static final long serialVersionUID = 1L;
039
040 private final Location at;
041 private final String workspaceName;
042 private Location actualLocation;
043
044 /**
045 * Create a request to verify the existance and location of a node at the supplied location.
046 *
047 * @param at the location of the node to be verified
048 * @param workspaceName the name of the workspace containing the node
049 * @throws IllegalArgumentException if the location or workspace name is null
050 */
051 public VerifyNodeExistsRequest( Location at,
052 String workspaceName ) {
053 CheckArg.isNotNull(at, "at");
054 CheckArg.isNotNull(workspaceName, "workspaceName");
055 this.workspaceName = workspaceName;
056 this.at = at;
057 }
058
059 /**
060 * {@inheritDoc}
061 *
062 * @see org.jboss.dna.graph.request.Request#isReadOnly()
063 */
064 @Override
065 public boolean isReadOnly() {
066 return true;
067 }
068
069 /**
070 * Get the location defining the node that is to be read.
071 *
072 * @return the location of the node; never null
073 */
074 public Location at() {
075 return at;
076 }
077
078 /**
079 * Get the name of the workspace in which the node exists.
080 *
081 * @return the name of the workspace; never null
082 */
083 public String inWorkspace() {
084 return workspaceName;
085 }
086
087 /**
088 * Sets the actual and complete location of the node whose properties have been read. This method must be called when
089 * processing the request, and the actual location must have a {@link Location#getPath() path}.
090 *
091 * @param actual the actual location of the node being read, or null if the {@link #at() current location} should be used
092 * @throws IllegalArgumentException if the actual location does not represent the {@link Location#isSame(Location) same
093 * location} as the {@link #at() current location}, or if the actual location does not have a path.
094 * @throws IllegalStateException if the request is frozen
095 */
096 public void setActualLocationOfNode( Location actual ) {
097 checkNotFrozen();
098 if (!at.isSame(actual)) { // not same if actual is null
099 throw new IllegalArgumentException(GraphI18n.actualLocationIsNotSameAsInputLocation.text(actual, at));
100 }
101 assert actual != null;
102 if (!actual.hasPath()) {
103 throw new IllegalArgumentException(GraphI18n.actualLocationMustHavePath.text(actual));
104 }
105 this.actualLocation = actual;
106 }
107
108 /**
109 * Get the actual location of the node whose properties were read.
110 *
111 * @return the actual location, or null if the actual location was not set
112 */
113 public Location getActualLocationOfNode() {
114 return actualLocation;
115 }
116
117 /**
118 * Return whether this node is known to exist. If the request has been processed, it will have an
119 * {@link #getActualLocationOfNode() actual location} or an {@link #getError() error}.
120 *
121 * @return true if this node is known to exist
122 * @see #getActualLocationOfNode()
123 * @see #getError()
124 */
125 public boolean exists() {
126 return actualLocation != null;
127 }
128
129 /**
130 * {@inheritDoc}
131 *
132 * @see org.jboss.dna.graph.request.Request#cancel()
133 */
134 @Override
135 public void cancel() {
136 super.cancel();
137 this.actualLocation = null;
138 }
139
140 /**
141 * {@inheritDoc}
142 *
143 * @see java.lang.Object#hashCode()
144 */
145 @Override
146 public int hashCode() {
147 return HashCode.compute(at, workspaceName);
148 }
149
150 /**
151 * {@inheritDoc}
152 *
153 * @see java.lang.Object#equals(java.lang.Object)
154 */
155 @Override
156 public boolean equals( Object obj ) {
157 if (obj == this) return true;
158 if (this.getClass().isInstance(obj)) {
159 VerifyNodeExistsRequest that = (VerifyNodeExistsRequest)obj;
160 if (!this.at().equals(that.at())) return false;
161 if (!this.inWorkspace().equals(that.inWorkspace())) return false;
162 return true;
163 }
164 return false;
165 }
166
167 /**
168 * {@inheritDoc}
169 *
170 * @see java.lang.Object#toString()
171 */
172 @Override
173 public String toString() {
174 return "verify node exists at " + at() + " in the \"" + workspaceName + "\" workspace";
175 }
176 }