/* * Copyright (c) 1999, 2004, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package javax.naming.spi; import javax.naming.*; import java.util.Hashtable; /** * This interface represents a factory for obtaining the state of an * object for binding. *
* The JNDI framework allows for object implementations to * be loaded in dynamically via object factories. * For example, when looking up a printer bound in the name space, * if the print service binds printer names to {@code Reference}s, the printer * {@code Reference} could be used to create a printer object, so that * the caller of lookup can directly operate on the printer object * after the lookup. *
An {@code ObjectFactory} is responsible * for creating objects of a specific type. In the above example, * you may have a {@code PrinterObjectFactory} for creating * {@code Printer} objects. *
* For the reverse process, when an object is bound into the namespace, * JNDI provides state factories. * Continuing with the printer example, suppose the printer object is * updated and rebound: *
* The service provider for {@code ctx} uses a state factory * to obtain the state of {@code printer} for binding into its namespace. * A state factory for the {@code Printer} type object might return * a more compact object for storage in the naming system. ** ctx.rebind("inky", printer); *
* A state factory must implement the {@code StateFactory} interface. * In addition, the factory class must be public and must have a * public constructor that accepts no parameters. *
* The {@code getStateToBind()} method of a state factory may * be invoked multiple times, possibly using different parameters. * The implementation is thread-safe. *
* {@code StateFactory} is intended for use with service providers * that implement only the {@code Context} interface. * {@code DirStateFactory} is intended for use with service providers * that implement the {@code DirContext} interface. * * @author Rosanna Lee * @author Scott Seligman * * @see NamingManager#getStateToBind * @see DirectoryManager#getStateToBind * @see ObjectFactory * @see DirStateFactory * @since 1.3 */ public interface StateFactory { /** * Retrieves the state of an object for binding. *
* {@code NamingManager.getStateToBind()} * successively loads in state factories and invokes this method * on them until one produces a non-null answer. * {@code DirectoryManager.getStateToBind()} * successively loads in state factories. If a factory implements * {@code DirStateFactory}, then {@code DirectoryManager} * invokes {@code DirStateFactory.getStateToBind()}; otherwise * it invokes {@code StateFactory.getStateToBind()}. *
When an exception * is thrown by a factory, the exception is passed on to the caller * of {@code NamingManager.getStateToBind()} and * {@code DirectoryManager.getStateToBind()}. * The search for other factories * that may produce a non-null answer is halted. * A factory should only throw an exception if it is sure that * it is the only intended factory and that no other factories * should be tried. * If this factory cannot create an object using the arguments supplied, * it should return null. *
* The name
and nameCtx
parameters may
* optionally be used to specify the name of the object being created.
* See the description of "Name and Context Parameters" in
* {@link ObjectFactory#getObjectInstance ObjectFactory.getObjectInstance()}
* for details.
* If a factory uses nameCtx
it should synchronize its use
* against concurrent access, since context implementations are not
* guaranteed to be thread-safe.
*
* The {@code name} and {@code environment} parameters
* are owned by the caller.
* The implementation will not modify these objects or keep references
* to them, although it may keep references to clones or copies.
*
* @param obj A non-null object whose state is to be retrieved.
* @param name The name of this object relative to nameCtx
,
* or null if no name is specified.
* @param nameCtx The context relative to which the name
* parameter is specified, or null if name
is
* relative to the default initial context.
* @param environment The possibly null environment to
* be used in the creation of the object's state.
* @return The object's state for binding;
* null if the factory is not returning any changes.
* @exception NamingException if this factory encountered an exception
* while attempting to get the object's state, and no other factories are
* to be tried.
*
* @see NamingManager#getStateToBind
* @see DirectoryManager#getStateToBind
*/
public Object getStateToBind(Object obj, Name name, Context nameCtx,
Hashtable,?> environment)
throws NamingException;
}