001 /* Reference.java --
002 Copyright (C) 2000, 2001, 2005, 2006 Free Software Foundation, Inc.
003
004 This file is part of GNU Classpath.
005
006 GNU Classpath is free software; you can redistribute it and/or modify
007 it under the terms of the GNU General Public License as published by
008 the Free Software Foundation; either version 2, or (at your option)
009 any later version.
010
011 GNU Classpath is distributed in the hope that it will be useful, but
012 WITHOUT ANY WARRANTY; without even the implied warranty of
013 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
014 General Public License for more details.
015
016 You should have received a copy of the GNU General Public License
017 along with GNU Classpath; see the file COPYING. If not, write to the
018 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
019 02110-1301 USA.
020
021 Linking this library statically or dynamically with other modules is
022 making a combined work based on this library. Thus, the terms and
023 conditions of the GNU General Public License cover the whole
024 combination.
025
026 As a special exception, the copyright holders of this library give you
027 permission to link this library with independent modules to produce an
028 executable, regardless of the license terms of these independent
029 modules, and to copy and distribute the resulting executable under
030 terms of your choice, provided that you also meet, for each linked
031 independent module, the terms and conditions of the license of that
032 module. An independent module is a module which is not derived from
033 or based on this library. If you modify this library, you may extend
034 this exception to your version of the library, but you are not
035 obligated to do so. If you do not wish to do so, delete this
036 exception statement from your version. */
037
038
039 package javax.naming;
040
041 import java.io.Serializable;
042 import java.util.Enumeration;
043 import java.util.Vector;
044
045 /**
046 * This class represents a reference to an object that is located outside of the
047 * naming/directory system.
048 *
049 * @see Referenceable
050 *
051 * @author Tom Tromey (tromey@redhat.com)
052 */
053 public class Reference implements Cloneable, Serializable
054 {
055 private static final long serialVersionUID = - 1673475790065791735L;
056
057 /**
058 * The list of addresses, stored in this reference. The object may be
059 * have by several different addresses.
060 */
061 protected Vector<RefAddr> addrs;
062
063 /**
064 * The name of the class factory to create an instance of the object,
065 * referenced by this reference.
066 */
067 protected String classFactory;
068
069 /**
070 * The location, from where the class factory should be loaded.
071 */
072 protected String classFactoryLocation;
073
074 /**
075 * The name of the class of the object, to that this reference refers.
076 */
077 protected String className;
078
079 /**
080 * Create a new reference that is referencting to the object of the
081 * specified class.
082 */
083 public Reference (String className)
084 {
085 this.className = className;
086 addrs = new Vector<RefAddr> ();
087 }
088
089 /**
090 * Create a new reference that is referencing to the object of the
091 * specified class with the given address.
092 */
093 public Reference (String className, RefAddr addr)
094 {
095 this.className = className;
096 addrs = new Vector<RefAddr> ();
097 addrs.add (addr);
098 }
099
100 /**
101 * Create a new reference that is referencing to the object of the
102 * specified class, specifying the class and location of the factory that
103 * produces these objects.
104 *
105 * @param className the object class name
106 * @param factoryClassName the object factory class name
107 * @param factoryLocation the object factory location
108 */
109 public Reference (String className, String factoryClassName,
110 String factoryLocation)
111 {
112 this.className = className;
113 this.classFactory = factoryClassName;
114 this.classFactoryLocation = factoryLocation;
115 addrs = new Vector<RefAddr> ();
116 }
117
118 /**
119 * Create a new reference that is referencing to the object of the
120 * specified class, specifying the class and location of the factory that
121 * produces these objects and also the address of this object.
122 *
123 * @param className the object class name
124 * @param addr the address of the object
125 * @param factoryClassName the object factory class name
126 * @param factoryLocation the object factory location
127 */
128 public Reference (String className, RefAddr addr,
129 String factoryClassName, String factoryLocation)
130 {
131 this.className = className;
132 this.classFactory = factoryClassName;
133 this.classFactoryLocation = factoryLocation;
134 addrs = new Vector<RefAddr> ();
135 addrs.add (addr);
136 }
137
138 /**
139 * Add the new address for this object at the given position of the
140 * address list.
141 */
142 public void add (int posn, RefAddr addr)
143 {
144 addrs.add (posn, addr);
145 }
146
147 /**
148 * Appends the new object address to the end of the address list.
149 */
150 public void add (RefAddr addr)
151 {
152 addrs.add (addr);
153 }
154
155 /**
156 * Removes all defined addresses of the object.
157 */
158 public void clear ()
159 {
160 addrs.clear ();
161 }
162
163 public Object clone ()
164 {
165 Reference r = new Reference (className, classFactory,
166 classFactoryLocation);
167 r.addrs = (Vector<RefAddr>) addrs.clone ();
168 return r;
169 }
170
171 // Convenience function.
172 private boolean equals (String a, String b)
173 {
174 return (a == null) ? (b == null) : a.equals (b);
175 }
176
177 /**
178 * Compares two addresses for equality, by value.
179 */
180 public boolean equals (Object obj)
181 {
182 if (! (obj instanceof Reference))
183 return false;
184 Reference r = (Reference) obj;
185 return (equals (classFactory, r.classFactory)
186 && equals (classFactoryLocation, r.classFactoryLocation)
187 && equals (className, r.className)
188 && addrs.equals (r.addrs));
189 }
190
191 /**
192 * Get the address of this object at the given position.
193 */
194 public RefAddr get (int posn)
195 {
196 return addrs.get (posn);
197 }
198
199 /**
200 * Get the given type of address for this object.
201 *
202 * @param addrType the needed type of address
203 *
204 * @return the address of this object, having the specified type. If there
205 * is no address of such type, null is returned.
206 */
207 public RefAddr get (String addrType)
208 {
209 for (int i = 0; i < addrs.size (); ++i)
210 {
211 RefAddr r = addrs.get (i);
212 if (addrType.equals (r.getType ()))
213 return r;
214 }
215 return null;
216 }
217
218 /**
219 * Get the enumeration over all defined addresses of the object.
220 */
221 public Enumeration<RefAddr> getAll ()
222 {
223 return addrs.elements ();
224 }
225
226 /**
227 * Get the name of the class of the referenced object.
228 *
229 * @see #className
230 */
231 public String getClassName ()
232 {
233 return className;
234 }
235
236 /**
237 * Get the location of the factory class of the referenced object.
238 *
239 * @see #classFactoryLocation
240 */
241 public String getFactoryClassLocation ()
242 {
243 return classFactoryLocation;
244 }
245
246 /**
247 * Get the name of the factory class of the referenced object
248 *
249 * @see #classFactory
250 */
251 public String getFactoryClassName ()
252 {
253 return classFactory;
254 }
255
256 /**
257 * Get the hashcode of this reference.
258 *
259 * @return the sum of the hash codes of the addresses.
260 */
261 public int hashCode ()
262 {
263 // The spec says the hash code is the sum of the hash codes of the
264 // addresses. It does not mention the other fields.
265 int h = 0;
266 for (int i = 0; i < addrs.size (); ++i)
267 h += addrs.get (i).hashCode ();
268 return h;
269 }
270
271 /**
272 * Remove the address at the given position.
273 *
274 * @param posn the position of the address to remove
275 *
276 * @return the removed address
277 */
278 public Object remove (int posn)
279 {
280 return addrs.remove (posn);
281 }
282
283 /**
284 * Return the number of the defined addresses.
285 */
286 public int size ()
287 {
288 return addrs.size ();
289 }
290
291 /**
292 * Return the string representation.
293 */
294 public String toString ()
295 {
296 String x = getClass ().toString () + "[";
297 for (int i = 0; i < addrs.size (); ++i)
298 {
299 if (i > 0)
300 x += ",";
301 x += addrs.get (i).toString ();
302 }
303 return x + "]";
304 }
305
306 }