001 /*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements. See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership. The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License. You may obtain a copy of the License at
009 *
010 * http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing,
013 * software distributed under the License is distributed on an
014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 * KIND, either express or implied. See the License for the
016 * specific language governing permissions and limitations
017 * under the License.
018 *
019 */
020 package org.apache.directory.shared.ldap.entry;
021
022 import javax.naming.NamingException;
023
024 import org.apache.directory.shared.i18n.I18n;
025 import org.apache.directory.shared.ldap.schema.SyntaxChecker;
026 import org.slf4j.Logger;
027 import org.slf4j.LoggerFactory;
028
029
030 /**
031 * A wrapper around byte[] values in entries.
032 *
033 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
034 * @version $Rev$, $Date$
035 */
036 public abstract class AbstractValue<T> implements Value<T>
037 {
038 /** logger for reporting errors that might not be handled properly upstream */
039 private static final Logger LOG = LoggerFactory.getLogger( AbstractValue.class );
040
041
042 /** the wrapped binary value */
043 protected T wrapped;
044
045 /** the canonical representation of the wrapped value */
046 protected T normalizedValue;
047
048 /** A flag set when the value has been normalized */
049 protected boolean normalized;
050
051 /** cached results of the isValid() method call */
052 protected Boolean valid;
053
054 /** A flag set if the normalized data is different from the wrapped data */
055 protected transient boolean same;
056
057 /**
058 * Reset the value
059 */
060 public void clear()
061 {
062 wrapped = null;
063 normalized = false;
064 normalizedValue = null;
065 valid = null;
066 }
067
068
069 /**
070 * {@inheritDoc}
071 */
072 public Value<T> clone()
073 {
074 try
075 {
076 return (Value<T>)super.clone();
077 }
078 catch ( CloneNotSupportedException cnse )
079 {
080 // Do nothing
081 return null;
082 }
083 }
084
085
086 /**
087 * Gets a reference to the wrapped binary value.
088 *
089 * Warning ! The value is not copied !!!
090 *
091 * @return a direct handle on the binary value that is wrapped
092 */
093 public T getReference()
094 {
095 return wrapped;
096 }
097
098
099 /**
100 * Gets a copy of the wrapped binary value.
101 *
102 * @return a copy of the binary value that is wrapped
103 */
104 public T get()
105 {
106 // Just call the specific Client copy method.
107 return getCopy();
108 }
109
110
111 /**
112 * Gets the normalized (canonical) representation for the wrapped value.
113 * If the wrapped value is null, null is returned, otherwise the normalized
114 * form is returned. If the normalized Value is null, then the wrapped
115 * value is returned
116 *
117 * @return gets the normalized value
118 */
119 public T getNormalizedValue()
120 {
121 if ( isNull() )
122 {
123 return null;
124 }
125
126 if ( normalizedValue == null )
127 {
128 return getCopy();
129 }
130
131 return getNormalizedValueCopy();
132 }
133
134
135 /**
136 * Gets a reference to the the normalized (canonical) representation
137 * for the wrapped value.
138 *
139 * @return gets a reference to the normalized value
140 */
141 public T getNormalizedValueReference()
142 {
143 if ( isNull() )
144 {
145 return null;
146 }
147
148 if ( normalizedValue == null )
149 {
150 return wrapped;
151 }
152
153 return normalizedValue;
154
155 }
156
157
158 /**
159 * Check if the contained value is null or not
160 *
161 * @return <code>true</code> if the inner value is null.
162 */
163 public final boolean isNull()
164 {
165 return wrapped == null;
166 }
167
168
169 /**
170 * @return Tells if the wrapped value and the normalized value are the same
171 */
172 public final boolean isSame()
173 {
174 return same;
175 }
176
177
178 /**
179 * Check if the Valid flag is set or not. This flag is set by a call
180 * to the isValid( SyntaxChecker ) method for client values. It is overridden
181 * for server values.
182 *
183 * if the flag is not set, returns <code>false</code>
184 *
185 * @see ServerValue#isValid()
186 */
187 public boolean isValid()
188 {
189 if ( valid != null )
190 {
191 return valid;
192 }
193
194 return false;
195 }
196
197
198 /**
199 * Uses the syntaxChecker associated with the attributeType to check if the
200 * value is valid. Repeated calls to this method do not attempt to re-check
201 * the syntax of the wrapped value every time if the wrapped value does not
202 * change. Syntax checks only result on the first check, and when the wrapped
203 * value changes.
204 *
205 * @see ServerValue#isValid()
206 */
207 public final boolean isValid( SyntaxChecker syntaxChecker ) throws NamingException
208 {
209 if ( valid != null )
210 {
211 return valid;
212 }
213
214 if ( syntaxChecker == null )
215 {
216 String message = I18n.err( I18n.ERR_04139, toString() );
217 LOG.error( message );
218 throw new NamingException( message );
219 }
220
221 valid = syntaxChecker.isValidSyntax( getReference() );
222 return valid;
223 }
224
225
226 /**
227 * Normalize the value. In order to use this method, the Value
228 * must be schema aware.
229 *
230 * @exception NamingException If the value cannot be normalized
231 */
232 public void normalize() throws NamingException
233 {
234 normalized = true;
235 normalizedValue = wrapped;
236 }
237
238
239 /**
240 * Sets this value's wrapped value to a copy of the src array.
241 *
242 * @param wrapped the byte array to use as the wrapped value
243 */
244 public abstract void set( T wrapped );
245
246
247 /**
248 * Tells if the value has already be normalized or not.
249 *
250 * @return <code>true</code> if the value has already been normalized.
251 */
252 public final boolean isNormalized()
253 {
254 return normalized;
255 }
256
257
258 /**
259 * Set the normalized flag.
260 *
261 * @param the value : true or false
262 */
263 public final void setNormalized( boolean normalized )
264 {
265 this.normalized = normalized;
266 }
267 }