src/java.naming/share/classes/javax/naming/spi/NamingManager.java
changeset 47216 71c04702a3d5
parent 37782 ad8fe7507ecc
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/java.naming/share/classes/javax/naming/spi/NamingManager.java	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,924 @@
+/*
+ * Copyright (c) 1999, 2015, 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.net.MalformedURLException;
+import java.util.*;
+
+
+import javax.naming.*;
+import com.sun.naming.internal.VersionHelper;
+import com.sun.naming.internal.ResourceManager;
+import com.sun.naming.internal.FactoryEnumeration;
+
+/**
+ * This class contains methods for creating context objects
+ * and objects referred to by location information in the naming
+ * or directory service.
+ *<p>
+ * This class cannot be instantiated.  It has only static methods.
+ *<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.
+ *<p>
+ * NamingManager is safe for concurrent access by multiple threads.
+ *<p>
+ * Except as otherwise noted,
+ * a {@code Name} or environment parameter
+ * passed to any method is owned by the caller.
+ * The implementation will not modify the object or keep a reference
+ * to it, although it may keep a reference to a clone or copy.
+ *
+ * @author Rosanna Lee
+ * @author Scott Seligman
+ * @since 1.3
+ */
+
+public class NamingManager {
+
+    /*
+     * Disallow anyone from creating one of these.
+     * Made package private so that DirectoryManager can subclass.
+     */
+
+    NamingManager() {}
+
+    // should be protected and package private
+    static final VersionHelper helper = VersionHelper.getVersionHelper();
+
+// --------- object factory stuff
+
+    /**
+     * Package-private; used by DirectoryManager and NamingManager.
+     */
+    private static ObjectFactoryBuilder object_factory_builder = null;
+
+    /**
+     * The ObjectFactoryBuilder determines the policy used when
+     * trying to load object factories.
+     * See getObjectInstance() and class ObjectFactory for a description
+     * of the default policy.
+     * setObjectFactoryBuilder() overrides this default policy by installing
+     * an ObjectFactoryBuilder. Subsequent object factories will
+     * be loaded and created using the installed builder.
+     *<p>
+     * The builder can only be installed if the executing thread is allowed
+     * (by the security manager's checkSetFactory() method) to do so.
+     * Once installed, the builder cannot be replaced.
+     *
+     * @param builder The factory builder to install. If null, no builder
+     *                  is installed.
+     * @exception SecurityException builder cannot be installed
+     *          for security reasons.
+     * @exception NamingException builder cannot be installed for
+     *         a non-security-related reason.
+     * @exception IllegalStateException If a factory has already been installed.
+     * @see #getObjectInstance
+     * @see ObjectFactory
+     * @see ObjectFactoryBuilder
+     * @see java.lang.SecurityManager#checkSetFactory
+     */
+    public static synchronized void setObjectFactoryBuilder(
+            ObjectFactoryBuilder builder) throws NamingException {
+        if (object_factory_builder != null)
+            throw new IllegalStateException("ObjectFactoryBuilder already set");
+
+        SecurityManager security = System.getSecurityManager();
+        if (security != null) {
+            security.checkSetFactory();
+        }
+        object_factory_builder = builder;
+    }
+
+    /**
+     * Used for accessing object factory builder.
+     */
+    static synchronized ObjectFactoryBuilder getObjectFactoryBuilder() {
+        return object_factory_builder;
+    }
+
+
+    /**
+     * Retrieves the ObjectFactory for the object identified by a reference,
+     * using the reference's factory class name and factory codebase
+     * to load in the factory's class.
+     * @param ref The non-null reference to use.
+     * @param factoryName The non-null class name of the factory.
+     * @return The object factory for the object identified by ref; null
+     * if unable to load the factory.
+     */
+    static ObjectFactory getObjectFactoryFromReference(
+        Reference ref, String factoryName)
+        throws IllegalAccessException,
+        InstantiationException,
+        MalformedURLException {
+        Class<?> clas = null;
+
+        // Try to use current class loader
+        try {
+             clas = helper.loadClass(factoryName);
+        } catch (ClassNotFoundException e) {
+            // ignore and continue
+            // e.printStackTrace();
+        }
+        // All other exceptions are passed up.
+
+        // Not in class path; try to use codebase
+        String codebase;
+        if (clas == null &&
+                (codebase = ref.getFactoryClassLocation()) != null) {
+            try {
+                clas = helper.loadClass(factoryName, codebase);
+            } catch (ClassNotFoundException e) {
+            }
+        }
+
+        @SuppressWarnings("deprecation") // Class.newInstance
+        ObjectFactory result = (clas != null) ? (ObjectFactory) clas.newInstance() : null;
+        return result;
+    }
+
+
+    /**
+     * Creates an object using the factories specified in the
+     * {@code Context.OBJECT_FACTORIES} property of the environment
+     * or of the provider resource file associated with {@code nameCtx}.
+     *
+     * @return factory created; null if cannot create
+     */
+    private static Object createObjectFromFactories(Object obj, Name name,
+            Context nameCtx, Hashtable<?,?> environment) throws Exception {
+
+        FactoryEnumeration factories = ResourceManager.getFactories(
+            Context.OBJECT_FACTORIES, environment, nameCtx);
+
+        if (factories == null)
+            return null;
+
+        // Try each factory until one succeeds
+        ObjectFactory factory;
+        Object answer = null;
+        while (answer == null && factories.hasMore()) {
+            factory = (ObjectFactory)factories.next();
+            answer = factory.getObjectInstance(obj, name, nameCtx, environment);
+        }
+        return answer;
+    }
+
+    private static String getURLScheme(String str) {
+        int colon_posn = str.indexOf(':');
+        int slash_posn = str.indexOf('/');
+
+        if (colon_posn > 0 && (slash_posn == -1 || colon_posn < slash_posn))
+            return str.substring(0, colon_posn);
+        return null;
+    }
+
+    /**
+     * Creates an instance of an object for the specified object
+     * and environment.
+     * <p>
+     * If an object factory builder has been installed, it is used to
+     * create a factory for creating the object.
+     * Otherwise, the following rules are used to create the object:
+     *<ol>
+     * <li>If {@code refInfo} is a {@code Reference}
+     *    or {@code Referenceable} containing a factory class name,
+     *    use the named factory to create the object.
+     *    Return {@code refInfo} if the factory cannot be created.
+     *    Under JDK 1.1, if the factory class must be loaded from a location
+     *    specified in the reference, a {@code SecurityManager} must have
+     *    been installed or the factory creation will fail.
+     *    If an exception is encountered while creating the factory,
+     *    it is passed up to the caller.
+     * <li>If {@code refInfo} is a {@code Reference} or
+     *    {@code Referenceable} with no factory class name,
+     *    and the address or addresses are {@code StringRefAddr}s with
+     *    address type "URL",
+     *    try the URL context factory corresponding to each URL's scheme id
+     *    to create the object (see {@code getURLContext()}).
+     *    If that fails, continue to the next step.
+     * <li> Use the object factories specified in
+     *    the {@code Context.OBJECT_FACTORIES} property of the environment,
+     *    and of the provider resource file associated with
+     *    {@code nameCtx}, in that order.
+     *    The value of this property is a colon-separated list of factory
+     *    class names that are tried in order, and the first one that succeeds
+     *    in creating an object is the one used.
+     *    If none of the factories can be loaded,
+     *    return {@code refInfo}.
+     *    If an exception is encountered while creating the object, the
+     *    exception is passed up to the caller.
+     *</ol>
+     *<p>
+     * Service providers that implement the {@code DirContext}
+     * interface should use
+     * {@code DirectoryManager.getObjectInstance()}, not this method.
+     * Service providers that implement only the {@code Context}
+     * interface should use this method.
+     * <p>
+     * Note that an object factory (an object that implements the ObjectFactory
+     * interface) must be public and must have a public constructor that
+     * accepts no arguments.
+     * In cases where the factory is in a named module then it must be in a
+     * package which is exported by that module to the {@code java.naming}
+     * module.
+     * <p>
+     * The {@code name} and {@code nameCtx} parameters may
+     * optionally be used to specify the name of the object being created.
+     * {@code name} is the name of the object, relative to context
+     * {@code nameCtx}.  This information could be useful to the object
+     * factory or to the object implementation.
+     *  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} is null, {@code name} is relative
+     * to the default initial context.  If no name is being specified, the
+     * {@code name} parameter should be null.
+     *
+     * @param refInfo The possibly null object for which to create an object.
+     * @param name The name of this object relative to {@code nameCtx}.
+     *          Specifying a name is optional; if it is
+     *          omitted, {@code name} should be null.
+     * @param nameCtx The context relative to which the {@code name}
+     *          parameter is specified.  If null, {@code name} is
+     *          relative to the default initial context.
+     * @param environment The possibly null environment to
+     *          be used in the creation of the object factory and the object.
+     * @return An object created using {@code refInfo}; or
+     *          {@code refInfo} if an object cannot be created using
+     *          the algorithm described above.
+     * @exception NamingException if a naming exception was encountered
+     *  while attempting to get a URL context, or if one of the
+     *          factories accessed throws a NamingException.
+     * @exception Exception if one of the factories accessed throws an
+     *          exception, or if an error was encountered while loading
+     *          and instantiating the factory and object classes.
+     *          A factory should only throw an exception if it does not want
+     *          other factories to be used in an attempt to create an object.
+     *  See ObjectFactory.getObjectInstance().
+     * @see #getURLContext
+     * @see ObjectFactory
+     * @see ObjectFactory#getObjectInstance
+     */
+    public static Object
+        getObjectInstance(Object refInfo, Name name, Context nameCtx,
+                          Hashtable<?,?> environment)
+        throws Exception
+    {
+
+        ObjectFactory factory;
+
+        // Use builder if installed
+        ObjectFactoryBuilder builder = getObjectFactoryBuilder();
+        if (builder != null) {
+            // builder must return non-null factory
+            factory = builder.createObjectFactory(refInfo, environment);
+            return factory.getObjectInstance(refInfo, name, nameCtx,
+                environment);
+        }
+
+        // Use reference if possible
+        Reference ref = null;
+        if (refInfo instanceof Reference) {
+            ref = (Reference) refInfo;
+        } else if (refInfo instanceof Referenceable) {
+            ref = ((Referenceable)(refInfo)).getReference();
+        }
+
+        Object answer;
+
+        if (ref != null) {
+            String f = ref.getFactoryClassName();
+            if (f != null) {
+                // if reference identifies a factory, use exclusively
+
+                factory = getObjectFactoryFromReference(ref, f);
+                if (factory != null) {
+                    return factory.getObjectInstance(ref, name, nameCtx,
+                                                     environment);
+                }
+                // No factory found, so return original refInfo.
+                // Will reach this point if factory class is not in
+                // class path and reference does not contain a URL for it
+                return refInfo;
+
+            } else {
+                // if reference has no factory, check for addresses
+                // containing URLs
+
+                answer = processURLAddrs(ref, name, nameCtx, environment);
+                if (answer != null) {
+                    return answer;
+                }
+            }
+        }
+
+        // try using any specified factories
+        answer =
+            createObjectFromFactories(refInfo, name, nameCtx, environment);
+        return (answer != null) ? answer : refInfo;
+    }
+
+    /*
+     * Ref has no factory.  For each address of type "URL", try its URL
+     * context factory.  Returns null if unsuccessful in creating and
+     * invoking a factory.
+     */
+    static Object processURLAddrs(Reference ref, Name name, Context nameCtx,
+                                  Hashtable<?,?> environment)
+            throws NamingException {
+
+        for (int i = 0; i < ref.size(); i++) {
+            RefAddr addr = ref.get(i);
+            if (addr instanceof StringRefAddr &&
+                addr.getType().equalsIgnoreCase("URL")) {
+
+                String url = (String)addr.getContent();
+                Object answer = processURL(url, name, nameCtx, environment);
+                if (answer != null) {
+                    return answer;
+                }
+            }
+        }
+        return null;
+    }
+
+    private static Object processURL(Object refInfo, Name name,
+                                     Context nameCtx, Hashtable<?,?> environment)
+            throws NamingException {
+        Object answer;
+
+        // If refInfo is a URL string, try to use its URL context factory
+        // If no context found, continue to try object factories.
+        if (refInfo instanceof String) {
+            String url = (String)refInfo;
+            String scheme = getURLScheme(url);
+            if (scheme != null) {
+                answer = getURLObject(scheme, refInfo, name, nameCtx,
+                                      environment);
+                if (answer != null) {
+                    return answer;
+                }
+            }
+        }
+
+        // If refInfo is an array of URL strings,
+        // try to find a context factory for any one of its URLs.
+        // If no context found, continue to try object factories.
+        if (refInfo instanceof String[]) {
+            String[] urls = (String[])refInfo;
+            for (int i = 0; i <urls.length; i++) {
+                String scheme = getURLScheme(urls[i]);
+                if (scheme != null) {
+                    answer = getURLObject(scheme, refInfo, name, nameCtx,
+                                          environment);
+                    if (answer != null)
+                        return answer;
+                }
+            }
+        }
+        return null;
+    }
+
+
+    /**
+     * Retrieves a context identified by {@code obj}, using the specified
+     * environment.
+     * Used by ContinuationContext.
+     *
+     * @param obj       The object identifying the context.
+     * @param name      The name of the context being returned, relative to
+     *                  {@code nameCtx}, or null if no name is being
+     *                  specified.
+     *                  See the {@code getObjectInstance} method for
+     *                  details.
+     * @param nameCtx   The context relative to which {@code name} is
+     *                  specified, or null for the default initial context.
+     *                  See the {@code getObjectInstance} method for
+     *                  details.
+     * @param environment Environment specifying characteristics of the
+     *                  resulting context.
+     * @return A context identified by {@code obj}.
+     *
+     * @see #getObjectInstance
+     */
+    static Context getContext(Object obj, Name name, Context nameCtx,
+                              Hashtable<?,?> environment) throws NamingException {
+        Object answer;
+
+        if (obj instanceof Context) {
+            // %%% Ignore environment for now.  OK since method not public.
+            return (Context)obj;
+        }
+
+        try {
+            answer = getObjectInstance(obj, name, nameCtx, environment);
+        } catch (NamingException e) {
+            throw e;
+        } catch (Exception e) {
+            NamingException ne = new NamingException();
+            ne.setRootCause(e);
+            throw ne;
+        }
+
+        return (answer instanceof Context)
+            ? (Context)answer
+            : null;
+    }
+
+    // Used by ContinuationContext
+    static Resolver getResolver(Object obj, Name name, Context nameCtx,
+                                Hashtable<?,?> environment) throws NamingException {
+        Object answer;
+
+        if (obj instanceof Resolver) {
+            // %%% Ignore environment for now.  OK since method not public.
+            return (Resolver)obj;
+        }
+
+        try {
+            answer = getObjectInstance(obj, name, nameCtx, environment);
+        } catch (NamingException e) {
+            throw e;
+        } catch (Exception e) {
+            NamingException ne = new NamingException();
+            ne.setRootCause(e);
+            throw ne;
+        }
+
+        return (answer instanceof Resolver)
+            ? (Resolver)answer
+            : null;
+    }
+
+
+    /***************** URL Context implementations ***************/
+
+    /**
+     * Creates a context for the given URL scheme id.
+     * <p>
+     * The resulting context is for resolving URLs of the
+     * scheme {@code scheme}. The resulting context is not tied
+     * to a specific URL. It is able to handle arbitrary URLs with
+     * the specified scheme.
+     *<p>
+     * The class name of the factory that creates the resulting context
+     * has the naming convention <i>scheme-id</i>URLContextFactory
+     * (e.g. "ftpURLContextFactory" for the "ftp" scheme-id),
+     * in the package specified as follows.
+     * The {@code Context.URL_PKG_PREFIXES} environment property (which
+     * may contain values taken from system properties,
+     * or application resource files)
+     * contains a colon-separated list of package prefixes.
+     * Each package prefix in
+     * the property is tried in the order specified to load the factory class.
+     * The default package prefix is "com.sun.jndi.url" (if none of the
+     * specified packages work, this default is tried).
+     * The complete package name is constructed using the package prefix,
+     * concatenated with the scheme id.
+     *<p>
+     * For example, if the scheme id is "ldap", and the
+     * {@code Context.URL_PKG_PREFIXES} property
+     * contains "com.widget:com.wiz.jndi",
+     * the naming manager would attempt to load the following classes
+     * until one is successfully instantiated:
+     *<ul>
+     * <li>com.widget.ldap.ldapURLContextFactory
+     *  <li>com.wiz.jndi.ldap.ldapURLContextFactory
+     *  <li>com.sun.jndi.url.ldap.ldapURLContextFactory
+     *</ul>
+     * If none of the package prefixes work, null is returned.
+     *<p>
+     * If a factory is instantiated, it is invoked with the following
+     * parameters to produce the resulting context.
+     * <p>
+     * {@code factory.getObjectInstance(null, environment);}
+     * <p>
+     * For example, invoking getObjectInstance() as shown above
+     * on a LDAP URL context factory would return a
+     * context that can resolve LDAP urls
+     * (e.g. "ldap://ldap.wiz.com/o=wiz,c=us",
+     * "ldap://ldap.umich.edu/o=umich,c=us", ...).
+     *<p>
+     * Note that an object factory (an object that implements the ObjectFactory
+     * interface) must be public and must have a public constructor that
+     * accepts no arguments.
+     * In cases where the factory is in a named module then it must be in a
+     * package which is exported by that module to the {@code java.naming}
+     * module.
+     *
+     * @param scheme    The non-null scheme-id of the URLs supported by the context.
+     * @param environment The possibly null environment properties to be
+     *           used in the creation of the object factory and the context.
+     * @return A context for resolving URLs with the
+     *         scheme id {@code scheme};
+     *  {@code null} if the factory for creating the
+     *         context is not found.
+     * @exception NamingException If a naming exception occurs while creating
+     *          the context.
+     * @see #getObjectInstance
+     * @see ObjectFactory#getObjectInstance
+     */
+    public static Context getURLContext(String scheme,
+                                        Hashtable<?,?> environment)
+        throws NamingException
+    {
+        // pass in 'null' to indicate creation of generic context for scheme
+        // (i.e. not specific to a URL).
+
+            Object answer = getURLObject(scheme, null, null, null, environment);
+            if (answer instanceof Context) {
+                return (Context)answer;
+            } else {
+                return null;
+            }
+    }
+
+    private static final String defaultPkgPrefix = "com.sun.jndi.url";
+
+    /**
+     * Creates an object for the given URL scheme id using
+     * the supplied urlInfo.
+     * <p>
+     * If urlInfo is null, the result is a context for resolving URLs
+     * with the scheme id 'scheme'.
+     * If urlInfo is a URL, the result is a context named by the URL.
+     * Names passed to this context is assumed to be relative to this
+     * context (i.e. not a URL). For example, if urlInfo is
+     * "ldap://ldap.wiz.com/o=Wiz,c=us", the resulting context will
+     * be that pointed to by "o=Wiz,c=us" on the server 'ldap.wiz.com'.
+     * Subsequent names that can be passed to this context will be
+     * LDAP names relative to this context (e.g. cn="Barbs Jensen").
+     * If urlInfo is an array of URLs, the URLs are assumed
+     * to be equivalent in terms of the context to which they refer.
+     * The resulting context is like that of the single URL case.
+     * If urlInfo is of any other type, that is handled by the
+     * context factory for the URL scheme.
+     * @param scheme the URL scheme id for the context
+     * @param urlInfo information used to create the context
+     * @param name name of this object relative to {@code nameCtx}
+     * @param nameCtx Context whose provider resource file will be searched
+     *          for package prefix values (or null if none)
+     * @param environment Environment properties for creating the context
+     * @see javax.naming.InitialContext
+     */
+    private static Object getURLObject(String scheme, Object urlInfo,
+                                       Name name, Context nameCtx,
+                                       Hashtable<?,?> environment)
+            throws NamingException {
+
+        // e.g. "ftpURLContextFactory"
+        ObjectFactory factory = (ObjectFactory)ResourceManager.getFactory(
+            Context.URL_PKG_PREFIXES, environment, nameCtx,
+            "." + scheme + "." + scheme + "URLContextFactory", defaultPkgPrefix);
+
+        if (factory == null)
+          return null;
+
+        // Found object factory
+        try {
+            return factory.getObjectInstance(urlInfo, name, nameCtx, environment);
+        } catch (NamingException e) {
+            throw e;
+        } catch (Exception e) {
+            NamingException ne = new NamingException();
+            ne.setRootCause(e);
+            throw ne;
+        }
+
+    }
+
+
+// ------------ Initial Context Factory Stuff
+    private static InitialContextFactoryBuilder initctx_factory_builder = null;
+
+    /**
+     * Use this method for accessing initctx_factory_builder while
+     * inside an unsynchronized method.
+     */
+    private static synchronized InitialContextFactoryBuilder
+    getInitialContextFactoryBuilder() {
+        return initctx_factory_builder;
+    }
+
+    /**
+     * Creates an initial context using the specified environment
+     * properties.
+     * <p>
+     * This is done as follows:
+     * <ul>
+     * <li>If an InitialContextFactoryBuilder has been installed,
+     *     it is used to create the factory for creating the initial
+     *     context</li>
+     * <li>Otherwise, the class specified in the
+     *     {@code Context.INITIAL_CONTEXT_FACTORY} environment property
+     *     is used
+     *     <ul>
+     *     <li>First, the {@linkplain java.util.ServiceLoader ServiceLoader}
+     *         mechanism tries to locate an {@code InitialContextFactory}
+     *         provider using the current thread's context class loader</li>
+     *     <li>Failing that, this implementation tries to locate a suitable
+     *         {@code InitialContextFactory} using a built-in mechanism
+     *         <br>
+     *         (Note that an initial context factory (an object that implements
+     *         the InitialContextFactory interface) must be public and must have
+     *         a public constructor that accepts no arguments.
+     *         In cases where the factory is in a named module then it must
+     *         be in a package which is exported by that module to the
+     *         {@code java.naming} module.)</li>
+     *     </ul>
+     * </li>
+     * </ul>
+     * @param env The possibly null environment properties used when
+     *                  creating the context.
+     * @return A non-null initial context.
+     * @exception NoInitialContextException If the
+     *          {@code Context.INITIAL_CONTEXT_FACTORY} property
+     *         is not found or names a nonexistent
+     *         class or a class that cannot be instantiated,
+     *          or if the initial context could not be created for some other
+     *          reason.
+     * @exception NamingException If some other naming exception was encountered.
+     * @see javax.naming.InitialContext
+     * @see javax.naming.directory.InitialDirContext
+     */
+    public static Context getInitialContext(Hashtable<?,?> env)
+        throws NamingException {
+        InitialContextFactory factory = null;
+
+        InitialContextFactoryBuilder builder = getInitialContextFactoryBuilder();
+        if (builder == null) {
+            // No builder installed, use property
+            // Get initial context factory class name
+
+            String className = env != null ?
+                (String)env.get(Context.INITIAL_CONTEXT_FACTORY) : null;
+            if (className == null) {
+                NoInitialContextException ne = new NoInitialContextException(
+                    "Need to specify class name in environment or system " +
+                    "property, or in an application resource file: " +
+                    Context.INITIAL_CONTEXT_FACTORY);
+                throw ne;
+            }
+
+            ServiceLoader<InitialContextFactory> loader =
+                    ServiceLoader.load(InitialContextFactory.class);
+
+            Iterator<InitialContextFactory> iterator = loader.iterator();
+            try {
+                while (iterator.hasNext()) {
+                    InitialContextFactory f = iterator.next();
+                    if (f.getClass().getName().equals(className)) {
+                        factory = f;
+                        break;
+                    }
+                }
+            } catch (ServiceConfigurationError e) {
+                NoInitialContextException ne =
+                        new NoInitialContextException(
+                                "Cannot load initial context factory "
+                                        + "'" + className + "'");
+                ne.setRootCause(e);
+                throw ne;
+            }
+
+            if (factory == null) {
+                try {
+                    @SuppressWarnings("deprecation")
+                    Object o = helper.loadClass(className).newInstance();
+                    factory = (InitialContextFactory) o;
+                } catch (Exception e) {
+                    NoInitialContextException ne =
+                            new NoInitialContextException(
+                                    "Cannot instantiate class: " + className);
+                    ne.setRootCause(e);
+                    throw ne;
+                }
+            }
+        } else {
+            factory = builder.createInitialContextFactory(env);
+        }
+
+        return factory.getInitialContext(env);
+    }
+
+
+    /**
+     * Sets the InitialContextFactory builder to be builder.
+     *
+     *<p>
+     * The builder can only be installed if the executing thread is allowed by
+     * the security manager to do so. Once installed, the builder cannot
+     * be replaced.
+     * @param builder The initial context factory builder to install. If null,
+     *                no builder is set.
+     * @exception SecurityException builder cannot be installed for security
+     *                  reasons.
+     * @exception NamingException builder cannot be installed for
+     *         a non-security-related reason.
+     * @exception IllegalStateException If a builder was previous installed.
+     * @see #hasInitialContextFactoryBuilder
+     * @see java.lang.SecurityManager#checkSetFactory
+     */
+    public static synchronized void setInitialContextFactoryBuilder(
+        InitialContextFactoryBuilder builder)
+        throws NamingException {
+            if (initctx_factory_builder != null)
+                throw new IllegalStateException(
+                    "InitialContextFactoryBuilder already set");
+
+            SecurityManager security = System.getSecurityManager();
+            if (security != null) {
+                security.checkSetFactory();
+            }
+            initctx_factory_builder = builder;
+    }
+
+    /**
+     * Determines whether an initial context factory builder has
+     * been set.
+     * @return true if an initial context factory builder has
+     *           been set; false otherwise.
+     * @see #setInitialContextFactoryBuilder
+     */
+    public static boolean hasInitialContextFactoryBuilder() {
+        return (getInitialContextFactoryBuilder() != null);
+    }
+
+// -----  Continuation Context Stuff
+
+    /**
+     * Constant that holds the name of the environment property into
+     * which {@code getContinuationContext()} stores the value of its
+     * {@code CannotProceedException} parameter.
+     * This property is inherited by the continuation context, and may
+     * be used by that context's service provider to inspect the
+     * fields of the exception.
+     *<p>
+     * The value of this constant is "java.naming.spi.CannotProceedException".
+     *
+     * @see #getContinuationContext
+     * @since 1.3
+     */
+    public static final String CPE = "java.naming.spi.CannotProceedException";
+
+    /**
+     * Creates a context in which to continue a context operation.
+     *<p>
+     * In performing an operation on a name that spans multiple
+     * namespaces, a context from one naming system may need to pass
+     * the operation on to the next naming system.  The context
+     * implementation does this by first constructing a
+     * {@code CannotProceedException} containing information
+     * pinpointing how far it has proceeded.  It then obtains a
+     * continuation context from JNDI by calling
+     * {@code getContinuationContext}.  The context
+     * implementation should then resume the context operation by
+     * invoking the same operation on the continuation context, using
+     * the remainder of the name that has not yet been resolved.
+     *<p>
+     * Before making use of the {@code cpe} parameter, this method
+     * updates the environment associated with that object by setting
+     * the value of the property <a href="#CPE">{@code CPE}</a>
+     * to {@code cpe}.  This property will be inherited by the
+     * continuation context, and may be used by that context's
+     * service provider to inspect the fields of this exception.
+     *
+     * @param cpe
+     *          The non-null exception that triggered this continuation.
+     * @return A non-null Context object for continuing the operation.
+     * @exception NamingException If a naming exception occurred.
+     */
+    @SuppressWarnings("unchecked")
+    public static Context getContinuationContext(CannotProceedException cpe)
+            throws NamingException {
+
+        Hashtable<Object,Object> env = (Hashtable<Object,Object>)cpe.getEnvironment();
+        if (env == null) {
+            env = new Hashtable<>(7);
+        } else {
+            // Make a (shallow) copy of the environment.
+            env = (Hashtable<Object,Object>)env.clone();
+        }
+        env.put(CPE, cpe);
+
+        ContinuationContext cctx = new ContinuationContext(cpe, env);
+        return cctx.getTargetContext();
+    }
+
+// ------------ State Factory Stuff
+
+    /**
+     * Retrieves the state of an object for binding.
+     * <p>
+     * Service providers that implement the {@code DirContext} interface
+     * should use {@code DirectoryManager.getStateToBind()}, not this method.
+     * Service providers that implement only the {@code Context} interface
+     * should use this method.
+     *<p>
+     * This method uses the specified state factories in
+     * the {@code Context.STATE_FACTORIES} property from the environment
+     * properties, and from the provider resource file associated with
+     * {@code nameCtx}, in that order.
+     *    The value of this property is a colon-separated list of factory
+     *    class names that are tried in order, and the first one that succeeds
+     *    in returning the object's state is the one used.
+     * If no object's state can be retrieved in this way, return the
+     * object itself.
+     *    If an exception is encountered while retrieving the state, the
+     *    exception is passed up to the caller.
+     * <p>
+     * Note that a state factory
+     * (an object that implements the StateFactory
+     * interface) must be public and must have a public constructor that
+     * accepts no arguments.
+     * In cases where the factory is in a named module then it must be in a
+     * package which is exported by that module to the {@code java.naming}
+     * module.
+     * <p>
+     * The {@code name} and {@code 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.
+     * <p>
+     * This method may return a {@code Referenceable} object.  The
+     * service provider obtaining this object may choose to store it
+     * directly, or to extract its reference (using
+     * {@code Referenceable.getReference()}) and store that instead.
+     *
+     * @param obj The non-null object for which to get state to bind.
+     * @param name The name of this object relative to {@code nameCtx},
+     *          or null if no name is specified.
+     * @param nameCtx The context relative to which the {@code name}
+     *          parameter is specified, or null if {@code name} is
+     *          relative to the default initial context.
+     *  @param environment The possibly null environment to
+     *          be used in the creation of the state factory and
+     *  the object's state.
+     * @return The non-null object representing {@code obj}'s state for
+     *  binding.  It could be the object ({@code obj}) itself.
+     * @exception NamingException If one of the factories accessed throws an
+     *          exception, or if an error was encountered while loading
+     *          and instantiating the factory and object classes.
+     *          A factory should only throw an exception if it does not want
+     *          other factories to be used in an attempt to create an object.
+     *  See {@code StateFactory.getStateToBind()}.
+     * @see StateFactory
+     * @see StateFactory#getStateToBind
+     * @see DirectoryManager#getStateToBind
+     * @since 1.3
+     */
+    public static Object
+        getStateToBind(Object obj, Name name, Context nameCtx,
+                       Hashtable<?,?> environment)
+        throws NamingException
+    {
+
+        FactoryEnumeration factories = ResourceManager.getFactories(
+            Context.STATE_FACTORIES, environment, nameCtx);
+
+        if (factories == null) {
+            return obj;
+        }
+
+        // Try each factory until one succeeds
+        StateFactory factory;
+        Object answer = null;
+        while (answer == null && factories.hasMore()) {
+            factory = (StateFactory)factories.next();
+            answer = factory.getStateToBind(obj, name, nameCtx, environment);
+        }
+
+        return (answer != null) ? answer : obj;
+    }
+}