1 /*

     2  * Copyright (c) 1999, 2004, Oracle and/or its affiliates. All rights reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.  Oracle designates this

     8  * particular file as subject to the "Classpath" exception as provided

     9  * by Oracle in the LICENSE file that accompanied this code.

    10  *

    11  * This code is distributed in the hope that it will be useful, but WITHOUT

    12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    14  * version 2 for more details (a copy is included in the LICENSE file that

    15  * accompanied this code).

    16  *

    17  * You should have received a copy of the GNU General Public License version

    18  * 2 along with this work; if not, write to the Free Software Foundation,

    19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    20  *

    21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    22  * or visit www.oracle.com if you need additional information or have any

    23  * questions.

    24  */

    25 package javax.naming.spi;

    26 

    27 import javax.naming.*;

    28 import javax.naming.directory.Attributes;

    29 import java.util.Hashtable;

    30 

    31 /**

    32   * This interface represents a factory for obtaining the state of an

    33   * object and corresponding attributes for binding.

    34   *<p>

    35   * The JNDI framework allows for object implementations to

    36   * be loaded in dynamically via {@code object factories}.

    37   * <p>

    38   * A {@code DirStateFactory} extends {@code StateFactory}

    39   * by allowing an {@code Attributes} instance

    40   * to be supplied to and be returned by the {@code getStateToBind()} method.

    41   * {@code DirStateFactory} implementations are intended to be used by

    42   * {@code DirContext} service providers.

    43   * When a caller binds an object using {@code DirContext.bind()},

    44   * he might also specify a set of attributes to be bound with the object.

    45   * The object and attributes to be bound are passed to

    46   * the {@code getStateToBind()} method of a factory.

    47   * If the factory processes the object and attributes, it returns

    48   * a corresponding pair of object and attributes to be bound.

    49   * If the factory does not process the object, it must return null.

    50   *<p>

    51   * For example, a caller might bind a printer object with some printer-related

    52   * attributes.

    53   *<blockquote><pre>

    54   * ctx.rebind("inky", printer, printerAttrs);

    55   *</pre></blockquote>

    56   * An LDAP service provider for {@code ctx} uses a {@code DirStateFactory}

    57   * (indirectly via {@code DirectoryManager.getStateToBind()})

    58   * and gives it {@code printer} and {@code printerAttrs}. A factory for

    59   * an LDAP directory might turn {@code printer} into a set of attributes

    60   * and merge that with {@code printerAttrs}. The service provider then

    61   * uses the resulting attributes to create an LDAP entry and updates

    62   * the directory.

    63   *

    64   * <p> Since {@code DirStateFactory} extends {@code StateFactory}, it

    65   * has two {@code getStateToBind()} methods, where one

    66   * differs from the other by the attributes

    67   * argument. {@code DirectoryManager.getStateToBind()} will only use

    68   * the form that accepts the attributes argument, while

    69   * {@code NamingManager.getStateToBind()} will only use the form that

    70   * does not accept the attributes argument.

    71   *

    72   * <p> Either form of the {@code getStateToBind()} method of a

    73   * DirStateFactory may be invoked multiple times, possibly using different

    74   * parameters.  The implementation is thread-safe.

    75   *

    76   * @author Rosanna Lee

    77   * @author Scott Seligman

    78   *

    79   * @see DirectoryManager#getStateToBind

    80   * @see DirObjectFactory

    81   * @since 1.3

    82   */

    83 public interface DirStateFactory extends StateFactory {

    84 /**

    85  * Retrieves the state of an object for binding given the object and attributes

    86  * to be transformed.

    87  *<p>

    88  * {@code DirectoryManager.getStateToBind()}

    89  * successively loads in state factories. If a factory implements

    90  * {@code DirStateFactory}, {@code DirectoryManager} invokes this method;

    91  * otherwise, it invokes {@code StateFactory.getStateToBind()}.

    92  * It does this until a factory produces a non-null answer.

    93  *<p>

    94  * When an exception is thrown by a factory,

    95  * the exception is passed on to the caller

    96  * of {@code DirectoryManager.getStateToBind()}. The search for other factories

    97  * that may produce a non-null answer is halted.

    98  * A factory should only throw an exception if it is sure that

    99  * it is the only intended factory and that no other factories

   100  * should be tried.

   101  * If this factory cannot create an object using the arguments supplied,

   102  * it should return null.

   103  * <p>

   104  * The {@code name} and {@code nameCtx} parameters may

   105  * optionally be used to specify the name of the object being created.

   106  * See the description of "Name and Context Parameters" in

   107  * {@link ObjectFactory#getObjectInstance ObjectFactory.getObjectInstance()}

   108  * for details.

   109  * If a factory uses {@code nameCtx} it should synchronize its use

   110  * against concurrent access, since context implementations are not

   111  * guaranteed to be thread-safe.

   112  *<p>

   113  * The {@code name}, {@code inAttrs}, and {@code environment} parameters

   114  * are owned by the caller.

   115  * The implementation will not modify these objects or keep references

   116  * to them, although it may keep references to clones or copies.

   117  * The object returned by this method is owned by the caller.

   118  * The implementation will not subsequently modify it.

   119  * It will contain either a new {@code Attributes} object that is

   120  * likewise owned by the caller, or a reference to the original

   121  * {@code inAttrs} parameter.

   122  *

   123  * @param obj A possibly null object whose state is to be retrieved.

   124  * @param name The name of this object relative to {@code nameCtx},

   125  *              or null if no name is specified.

   126  * @param nameCtx The context relative to which the {@code name}

   127  *              parameter is specified, or null if {@code name} is

   128  *              relative to the default initial context.

   129  * @param environment The possibly null environment to

   130  *              be used in the creation of the object's state.

   131  * @param inAttrs The possibly null attributes to be bound with the object.

   132  *      The factory must not modify {@code inAttrs}.

   133  * @return A {@code Result} containing the object's state for binding

   134  * and the corresponding

   135  * attributes to be bound; null if the object don't use this factory.

   136  * @exception NamingException If this factory encountered an exception

   137  * while attempting to get the object's state, and no other factories are

   138  * to be tried.

   139  *

   140  * @see DirectoryManager#getStateToBind

   141  */

   142     public Result getStateToBind(Object obj, Name name, Context nameCtx,

   143                                  Hashtable<?,?> environment,

   144                                  Attributes inAttrs)

   145         throws NamingException;

   146 

   147 

   148         /**

   149          * An object/attributes pair for returning the result of

   150          * DirStateFactory.getStateToBind().

   151          */

   152     public static class Result {

   153         /**

   154          * The possibly null object to be bound.

   155          */

   156         private Object obj;

   157 

   158 

   159         /**

   160          * The possibly null attributes to be bound.

   161          */

   162         private Attributes attrs;

   163 

   164         /**

   165           * Constructs an instance of Result.

   166           *

   167           * @param obj The possibly null object to be bound.

   168           * @param outAttrs The possibly null attributes to be bound.

   169           */

   170         public Result(Object obj, Attributes outAttrs) {

   171             this.obj = obj;

   172             this.attrs = outAttrs;

   173         }

   174 

   175         /**

   176          * Retrieves the object to be bound.

   177          * @return The possibly null object to be bound.

   178          */

   179         public Object getObject() { return obj; };

   180 

   181         /**

   182          * Retrieves the attributes to be bound.

   183          * @return The possibly null attributes to be bound.

   184          */

   185         public Attributes getAttributes() { return attrs; };

   186 

   187     }

   188 }