/* * 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 java.util.Hashtable; import javax.naming.*; /** * This interface represents a factory for creating an object. *<p> * The JNDI framework allows for object implementations to * be loaded in dynamically via <em>object factories</em>. * For example, when looking up a printer bound in the name space, * if the print service binds printer names to References, the printer * 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. * <p>An <tt>ObjectFactory</tt> is responsible * for creating objects of a specific type. In the above example, * you may have a PrinterObjectFactory for creating Printer objects. *<p> * An object factory must implement the <tt>ObjectFactory</tt> interface. * In addition, the factory class must be public and must have a * public constructor that accepts no parameters. *<p> * The <tt>getObjectInstance()</tt> method of an object factory may * be invoked multiple times, possibly using different parameters. * The implementation is thread-safe. *<p> * The mention of URL in the documentation for this class refers to * a URL string as defined by RFC 1738 and its related RFCs. It is * any string that conforms to the syntax described therein, and * may not always have corresponding support in the java.net.URL * class or Web browsers. * * @author Rosanna Lee * @author Scott Seligman * * @see NamingManager#getObjectInstance * @see NamingManager#getURLContext * @see ObjectFactoryBuilder * @see StateFactory * @since 1.3 */ public interface ObjectFactory {/** * Creates an object using the location or reference information * specified. * <p> * Special requirements of this object are supplied * using <code>environment</code>. * An example of such an environment property is user identity * information. *<p> * <tt>NamingManager.getObjectInstance()</tt> * successively loads in object factories and invokes this method * on them until one produces a non-null answer. When an exception * is thrown by an object factory, the exception is passed on to the caller * of <tt>NamingManager.getObjectInstance()</tt> * (and no search is made for other factories * that may produce a non-null answer). * An object factory should only throw an exception if it is sure that * it is the only intended factory and that no other object factories * should be tried. * If this factory cannot create an object using the arguments supplied, * it should return null. *<p> * A <em>URL context factory</em> is a special ObjectFactory that * creates contexts for resolving URLs or objects whose locations * are specified by URLs. The <tt>getObjectInstance()</tt> method * of a URL context factory will obey the following rules. * <ol> * <li>If <code>obj</code> is null, create a context for resolving URLs of the * scheme associated with this factory. The resulting context is not tied * to a specific URL: it is able to handle arbitrary URLs with this factory's * scheme id. For example, invoking <tt>getObjectInstance()</tt> with * <code>obj</code> set to null on an LDAP URL context factory would return a * context that can resolve LDAP URLs * such as "ldap://ldap.wiz.com/o=wiz,c=us" and * "ldap://ldap.umich.edu/o=umich,c=us". * <li> * If <code>obj</code> is a URL string, create an object (typically a context) * identified by the URL. For example, suppose this is an LDAP URL context * factory. If <code>obj</code> is "ldap://ldap.wiz.com/o=wiz,c=us", * getObjectInstance() would return the context named by the distinguished * name "o=wiz, c=us" at the LDAP server ldap.wiz.com. This context can * then be used to resolve LDAP names (such as "cn=George") * relative to that context. * <li> * If <code>obj</code> is an array of URL strings, the assumption is that the * URLs are equivalent in terms of the context to which they refer. * Verification of whether the URLs are, or need to be, equivalent is up * to the context factory. The order of the URLs in the array is * not significant. * The object returned by getObjectInstance() is like that of the single * URL case. It is the object named by the URLs. * <li> * If <code>obj</code> is of any other type, the behavior of * <tt>getObjectInstance()</tt> is determined by the context factory * implementation. * </ol> * * <p> * The <tt>name</tt> and <tt>environment</tt> 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. * * <p> * <b>Name and Context Parameters.</b> * <a name=NAMECTX></a> * * The <code>name</code> and <code>nameCtx</code> parameters may * optionally be used to specify the name of the object being created. * <code>name</code> is the name of the object, relative to context * <code>nameCtx</code>. * If there are several possible contexts from which the object * could be named -- as will often be the case -- it is up to * the caller to select one. A good rule of thumb is to select the * "deepest" context available. * If <code>nameCtx</code> is null, <code>name</code> is relative * to the default initial context. If no name is being specified, the * <code>name</code> parameter should be null. * If a factory uses <code>nameCtx</code> it should synchronize its use * against concurrent access, since context implementations are not * guaranteed to be thread-safe. * <p> * * @param obj The possibly null object containing location or reference * information that can be used in creating an object. * @param name The name of this object relative to <code>nameCtx</code>, * or null if no name is specified. * @param nameCtx The context relative to which the <code>name</code> * parameter is specified, or null if <code>name</code> is * relative to the default initial context. * @param environment The possibly null environment that is used in * creating the object. * @return The object created; null if an object cannot be created. * @exception Exception if this object factory encountered an exception * while attempting to create an object, and no other object factories are * to be tried. * * @see NamingManager#getObjectInstance * @see NamingManager#getURLContext */ public Object getObjectInstance(Object obj, Name name, Context nameCtx, Hashtable<?,?> environment) throws Exception;}
/*
* 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 java.util.Hashtable;
import javax.naming.*;
/**
* This interface represents a factory for creating an object.
*<p>
* The JNDI framework allows for object implementations to
* be loaded in dynamically via <em>object factories</em>.
* For example, when looking up a printer bound in the name space,
* if the print service binds printer names to References, the printer
* 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.
* <p>An <tt>ObjectFactory</tt> is responsible
* for creating objects of a specific type. In the above example,
* you may have a PrinterObjectFactory for creating Printer objects.
*<p>
* An object factory must implement the <tt>ObjectFactory</tt> interface.
* In addition, the factory class must be public and must have a
* public constructor that accepts no parameters.
*<p>
* The <tt>getObjectInstance()</tt> method of an object factory may
* be invoked multiple times, possibly using different parameters.
* The implementation is thread-safe.
*<p>
* The mention of URL in the documentation for this class refers to
* a URL string as defined by RFC 1738 and its related RFCs. It is
* any string that conforms to the syntax described therein, and
* may not always have corresponding support in the java.net.URL
* class or Web browsers.
*
* @author Rosanna Lee
* @author Scott Seligman
*
* @see NamingManager#getObjectInstance
* @see NamingManager#getURLContext
* @see ObjectFactoryBuilder
* @see StateFactory
* @since 1.3
*/
public interface ObjectFactory {
/**
* Creates an object using the location or reference information
* specified.
* <p>
* Special requirements of this object are supplied
* using <code>environment</code>.
* An example of such an environment property is user identity
* information.
*<p>
* <tt>NamingManager.getObjectInstance()</tt>
* successively loads in object factories and invokes this method
* on them until one produces a non-null answer. When an exception
* is thrown by an object factory, the exception is passed on to the caller
* of <tt>NamingManager.getObjectInstance()</tt>
* (and no search is made for other factories
* that may produce a non-null answer).
* An object factory should only throw an exception if it is sure that
* it is the only intended factory and that no other object factories
* should be tried.
* If this factory cannot create an object using the arguments supplied,
* it should return null.
*<p>
* A <em>URL context factory</em> is a special ObjectFactory that
* creates contexts for resolving URLs or objects whose locations
* are specified by URLs. The <tt>getObjectInstance()</tt> method
* of a URL context factory will obey the following rules.
* <ol>
* <li>If <code>obj</code> is null, create a context for resolving URLs of the
* scheme associated with this factory. The resulting context is not tied
* to a specific URL: it is able to handle arbitrary URLs with this factory's
* scheme id. For example, invoking <tt>getObjectInstance()</tt> with
* <code>obj</code> set to null on an LDAP URL context factory would return a
* context that can resolve LDAP URLs
* such as "ldap://ldap.wiz.com/o=wiz,c=us" and
* "ldap://ldap.umich.edu/o=umich,c=us".
* <li>
* If <code>obj</code> is a URL string, create an object (typically a context)
* identified by the URL. For example, suppose this is an LDAP URL context
* factory. If <code>obj</code> is "ldap://ldap.wiz.com/o=wiz,c=us",
* getObjectInstance() would return the context named by the distinguished
* name "o=wiz, c=us" at the LDAP server ldap.wiz.com. This context can
* then be used to resolve LDAP names (such as "cn=George")
* relative to that context.
* <li>
* If <code>obj</code> is an array of URL strings, the assumption is that the
* URLs are equivalent in terms of the context to which they refer.
* Verification of whether the URLs are, or need to be, equivalent is up
* to the context factory. The order of the URLs in the array is
* not significant.
* The object returned by getObjectInstance() is like that of the single
* URL case. It is the object named by the URLs.
* <li>
* If <code>obj</code> is of any other type, the behavior of
* <tt>getObjectInstance()</tt> is determined by the context factory
* implementation.
* </ol>
*
* <p>
* The <tt>name</tt> and <tt>environment</tt> 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.
*
* <p>
* <b>Name and Context Parameters.</b>
* <a name=NAMECTX></a>
*
* The <code>name</code> and <code>nameCtx</code> parameters may
* optionally be used to specify the name of the object being created.
* <code>name</code> is the name of the object, relative to context
* <code>nameCtx</code>.
* If there are several possible contexts from which the object
* could be named -- as will often be the case -- it is up to
* the caller to select one. A good rule of thumb is to select the
* "deepest" context available.
* If <code>nameCtx</code> is null, <code>name</code> is relative
* to the default initial context. If no name is being specified, the
* <code>name</code> parameter should be null.
* If a factory uses <code>nameCtx</code> it should synchronize its use
* against concurrent access, since context implementations are not
* guaranteed to be thread-safe.
* <p>
*
* @param obj The possibly null object containing location or reference
* information that can be used in creating an object.
* @param name The name of this object relative to <code>nameCtx</code>,
* or null if no name is specified.
* @param nameCtx The context relative to which the <code>name</code>
* parameter is specified, or null if <code>name</code> is
* relative to the default initial context.
* @param environment The possibly null environment that is used in
* creating the object.
* @return The object created; null if an object cannot be created.
* @exception Exception if this object factory encountered an exception
* while attempting to create an object, and no other object factories are
* to be tried.
*
* @see NamingManager#getObjectInstance
* @see NamingManager#getURLContext
*/
public Object getObjectInstance(Object obj, Name name, Context nameCtx,
Hashtable<?,?> environment)
throws Exception;
}