001 /*
002 * Copyright 1999-2004 Sun Microsystems, Inc. All Rights Reserved.
003 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
004 *
005 * This code is free software; you can redistribute it and/or modify it
006 * under the terms of the GNU General Public License version 2 only, as
007 * published by the Free Software Foundation. Sun designates this
008 * particular file as subject to the "Classpath" exception as provided
009 * by Sun in the LICENSE file that accompanied this code.
010 *
011 * This code is distributed in the hope that it will be useful, but WITHOUT
012 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
013 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
014 * version 2 for more details (a copy is included in the LICENSE file that
015 * accompanied this code).
016 *
017 * You should have received a copy of the GNU General Public License version
018 * 2 along with this work; if not, write to the Free Software Foundation,
019 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
020 *
021 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
022 * CA 95054 USA or visit www.sun.com if you need additional information or
023 * have any questions.
024 */
025 package javax.naming.spi;
026
027 import javax.naming.*;
028 import javax.naming.directory.Attributes;
029 import java.util.Hashtable;
030
031 /**
032 * This interface represents a factory for obtaining the state of an
033 * object and corresponding attributes for binding.
034 *<p>
035 * The JNDI framework allows for object implementations to
036 * be loaded in dynamically via <tt>object factories</tt>.
037 * <p>
038 * A <tt>DirStateFactory</tt> extends <tt>StateFactory</tt>
039 * by allowing an <tt>Attributes</tt> instance
040 * to be supplied to and be returned by the <tt>getStateToBind()</tt> method.
041 * <tt>DirStateFactory</tt> implementations are intended to be used by
042 * <tt>DirContext</tt> service providers.
043 * When a caller binds an object using <tt>DirContext.bind()</tt>,
044 * he might also specify a set of attributes to be bound with the object.
045 * The object and attributes to be bound are passed to
046 * the <tt>getStateToBind()</tt> method of a factory.
047 * If the factory processes the object and attributes, it returns
048 * a corresponding pair of object and attributes to be bound.
049 * If the factory does not process the object, it must return null.
050 *<p>
051 * For example, a caller might bind a printer object with some printer-related
052 * attributes.
053 *<blockquote><pre>
054 * ctx.rebind("inky", printer, printerAttrs);
055 *</pre></blockquote>
056 * An LDAP service provider for <tt>ctx</tt> uses a <tt>DirStateFactory</tt>
057 * (indirectly via <tt>DirectoryManager.getStateToBind()</tt>)
058 * and gives it <tt>printer</tt> and <tt>printerAttrs</tt>. A factory for
059 * an LDAP directory might turn <tt>printer</tt> into a set of attributes
060 * and merge that with <tt>printerAttrs</tt>. The service provider then
061 * uses the resulting attributes to create an LDAP entry and updates
062 * the directory.
063 *
064 * <p> Since <tt>DirStateFactory</tt> extends <tt>StateFactory</tt>, it
065 * has two <tt>getStateToBind()</tt> methods, where one
066 * differs from the other by the attributes
067 * argument. <tt>DirectoryManager.getStateToBind()</tt> will only use
068 * the form that accepts the attributes argument, while
069 * <tt>NamingManager.getStateToBind()</tt> will only use the form that
070 * does not accept the attributes argument.
071 *
072 * <p> Either form of the <tt>getStateToBind()</tt> method of a
073 * DirStateFactory may be invoked multiple times, possibly using different
074 * parameters. The implementation is thread-safe.
075 *
076 * @author Rosanna Lee
077 * @author Scott Seligman
078 * @version 1.18 07/05/05
079 *
080 * @see DirectoryManager#getStateToBind
081 * @see DirObjectFactory
082 * @since 1.3
083 */
084 public interface DirStateFactory extends StateFactory {
085 /**
086 * Retrieves the state of an object for binding given the object and attributes
087 * to be transformed.
088 *<p>
089 * <tt>DirectoryManager.getStateToBind()</tt>
090 * successively loads in state factories. If a factory implements
091 * <tt>DirStateFactory</tt>, <tt>DirectoryManager</tt> invokes this method;
092 * otherwise, it invokes <tt>StateFactory.getStateToBind()</tt>.
093 * It does this until a factory produces a non-null answer.
094 *<p>
095 * When an exception is thrown by a factory,
096 * the exception is passed on to the caller
097 * of <tt>DirectoryManager.getStateToBind()</tt>. The search for other factories
098 * that may produce a non-null answer is halted.
099 * A factory should only throw an exception if it is sure that
100 * it is the only intended factory and that no other factories
101 * should be tried.
102 * If this factory cannot create an object using the arguments supplied,
103 * it should return null.
104 * <p>
105 * The <code>name</code> and <code>nameCtx</code> parameters may
106 * optionally be used to specify the name of the object being created.
107 * See the description of "Name and Context Parameters" in
108 * {@link ObjectFactory#getObjectInstance ObjectFactory.getObjectInstance()}
109 * for details.
110 * If a factory uses <code>nameCtx</code> it should synchronize its use
111 * against concurrent access, since context implementations are not
112 * guaranteed to be thread-safe.
113 *<p>
114 * The <tt>name</tt>, <tt>inAttrs</tt>, and <tt>environment</tt> parameters
115 * are owned by the caller.
116 * The implementation will not modify these objects or keep references
117 * to them, although it may keep references to clones or copies.
118 * The object returned by this method is owned by the caller.
119 * The implementation will not subsequently modify it.
120 * It will contain either a new <tt>Attributes</tt> object that is
121 * likewise owned by the caller, or a reference to the original
122 * <tt>inAttrs</tt> parameter.
123 *
124 * @param obj A possibly null object whose state is to be retrieved.
125 * @param name The name of this object relative to <code>nameCtx</code>,
126 * or null if no name is specified.
127 * @param nameCtx The context relative to which the <code>name</code>
128 * parameter is specified, or null if <code>name</code> is
129 * relative to the default initial context.
130 * @param environment The possibly null environment to
131 * be used in the creation of the object's state.
132 * @param inAttrs The possibly null attributes to be bound with the object.
133 * The factory must not modify <tt>inAttrs</tt>.
134 * @return A <tt>Result</tt> containing the object's state for binding
135 * and the corresponding
136 * attributes to be bound; null if the object don't use this factory.
137 * @exception NamingException If this factory encountered an exception
138 * while attempting to get the object's state, and no other factories are
139 * to be tried.
140 *
141 * @see DirectoryManager#getStateToBind
142 */
143 public Result getStateToBind(Object obj, Name name,
144 Context nameCtx, Hashtable<?, ?> environment,
145 Attributes inAttrs) throws NamingException;
146
147 /**
148 * An object/attributes pair for returning the result of
149 * DirStateFactory.getStateToBind().
150 */
151 public static class Result {
152 /**
153 * The possibly null object to be bound.
154 */
155 private Object obj;
156
157 /**
158 * The possibly null attributes to be bound.
159 */
160 private Attributes attrs;
161
162 /**
163 * Constructs an instance of Result.
164 *
165 * @param obj The possibly null object to be bound.
166 * @param outAttrs The possibly null attributes to be bound.
167 */
168 public Result(Object obj, Attributes outAttrs) {
169 this .obj = obj;
170 this .attrs = outAttrs;
171 }
172
173 /**
174 * Retrieves the object to be bound.
175 * @return The possibly null object to be bound.
176 */
177 public Object getObject() {
178 return obj;
179 };
180
181 /**
182 * Retrieves the attributes to be bound.
183 * @return The possibly null attributes to be bound.
184 */
185 public Attributes getAttributes() {
186 return attrs;
187 };
188
189 }
190 }
|