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 import org.jboss.dna.graph.connector.RepositoryConnection;
031 import org.jboss.dna.graph.property.Name;
032 import org.jboss.dna.graph.property.Property;
033
034 /**
035 * Instruction to read a single property on the node at the specified location.
036 *
037 * @author Randall Hauch
038 */
039 public class ReadPropertyRequest extends CacheableRequest {
040
041 private static final long serialVersionUID = 1L;
042
043 private final Location on;
044 private final String workspaceName;
045 private final Name propertyName;
046 private Property property;
047 private Location actualLocation;
048
049 /**
050 * Create a request to read the properties and number of children of a node at the supplied location.
051 *
052 * @param on the location of the node to be read
053 * @param workspaceName the name of the workspace containing the node
054 * @param propertyName the name of the property to read
055 * @throws IllegalArgumentException if the location, workspace name, or property name are null
056 */
057 public ReadPropertyRequest( Location on,
058 String workspaceName,
059 Name propertyName ) {
060 CheckArg.isNotNull(on, "on");
061 CheckArg.isNotNull(propertyName, "propertyName");
062 CheckArg.isNotNull(workspaceName, "workspaceName");
063 this.workspaceName = workspaceName;
064 this.on = on;
065 this.propertyName = propertyName;
066 }
067
068 /**
069 * {@inheritDoc}
070 *
071 * @see org.jboss.dna.graph.request.Request#isReadOnly()
072 */
073 @Override
074 public boolean isReadOnly() {
075 return true;
076 }
077
078 /**
079 * Get the location defining the node that is to be read.
080 *
081 * @return the location of the node; never null
082 */
083 public Location on() {
084 return on;
085 }
086
087 /**
088 * Get the name of the workspace in which the node exists.
089 *
090 * @return the name of the workspace; never null
091 */
092 public String inWorkspace() {
093 return workspaceName;
094 }
095
096 /**
097 * Get the name of the property that is to be read
098 *
099 * @return the property name; never null
100 */
101 public Name named() {
102 return propertyName;
103 }
104
105 /**
106 * Get the property that was read.
107 *
108 * @return the property, or null if the property was not read or did not exist on the node
109 */
110 public Property getProperty() {
111 return property;
112 }
113
114 /**
115 * Set the property on the node as read from the {@link RepositoryConnection}
116 *
117 * @param property the property that was read
118 * @throws IllegalArgumentException if the property's name does not match the {@link #named() name of the property} that was
119 * to be read
120 * @throws IllegalStateException if the request is frozen
121 */
122 public void setProperty( Property property ) {
123 checkNotFrozen();
124 if (property != null) CheckArg.isEquals(property.getName(), "property's name", named(), "property name");
125 this.property = property;
126 }
127
128 /**
129 * Sets the actual and complete location of the node whose property has been read. This method must be called when processing
130 * the request, and the actual location must have a {@link Location#getPath() path}.
131 *
132 * @param actual the actual location of the node being read, or null if the {@link #on() current location} should be used
133 * @throws IllegalArgumentException if the actual location does not represent the {@link Location#isSame(Location) same
134 * location} as the {@link #on() current location}, or if the actual location does not have a path.
135 * @throws IllegalStateException if the request is frozen
136 */
137 public void setActualLocationOfNode( Location actual ) {
138 checkNotFrozen();
139 if (!on.isSame(actual)) { // not same if actual is null
140 throw new IllegalArgumentException(GraphI18n.actualLocationIsNotSameAsInputLocation.text(actual, on));
141 }
142 assert actual != null;
143 if (!actual.hasPath()) {
144 throw new IllegalArgumentException(GraphI18n.actualLocationMustHavePath.text(actual));
145 }
146 this.actualLocation = actual;
147 }
148
149 /**
150 * Get the actual location of the node whose property was read.
151 *
152 * @return the actual location, or null if the actual location was not set
153 */
154 public Location getActualLocationOfNode() {
155 return actualLocation;
156 }
157
158 /**
159 * {@inheritDoc}
160 *
161 * @see org.jboss.dna.graph.request.Request#cancel()
162 */
163 @Override
164 public void cancel() {
165 super.cancel();
166 this.actualLocation = null;
167 this.property = null;
168 }
169
170 /**
171 * {@inheritDoc}
172 *
173 * @see java.lang.Object#hashCode()
174 */
175 @Override
176 public int hashCode() {
177 return HashCode.compute(on, workspaceName, propertyName);
178 }
179
180 /**
181 * {@inheritDoc}
182 *
183 * @see java.lang.Object#equals(java.lang.Object)
184 */
185 @Override
186 public boolean equals( Object obj ) {
187 if (obj == this) return true;
188 if (this.getClass().isInstance(obj)) {
189 ReadPropertyRequest that = (ReadPropertyRequest)obj;
190 if (!this.on().equals(that.on())) return false;
191 if (!this.named().equals(that.named())) return false;
192 if (!this.inWorkspace().equals(that.inWorkspace())) return false;
193 return true;
194 }
195 return false;
196 }
197
198 /**
199 * {@inheritDoc}
200 *
201 * @see java.lang.Object#toString()
202 */
203 @Override
204 public String toString() {
205 return "read " + named() + " property on " + on() + " in the \"" + workspaceName + "\" workspace";
206 }
207
208 }