/*
* @(#)DirectoryManager.java 1.13 04/07/16
*
* Copyright 2004 Sun Microsystems, Inc. All rights reserved.
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*/
package javax.naming.spi;
import java.util.Hashtable;
import javax.naming.Context;
import javax.naming.Name;
import javax.naming.Reference;
import javax.naming.Referenceable;
import javax.naming.NamingException;
import javax.naming.CannotProceedException;
import javax.naming.directory.DirContext;
import javax.naming.directory.Attributes;
import com.sun.naming.internal.ResourceManager;
import com.sun.naming.internal.FactoryEnumeration;
/**
* This class contains methods for supporting <tt>DirContext</tt>
* implementations.
*<p>
* This class is an extension of <tt>NamingManager</tt>. It contains methods
* for use by service providers for accessing object factories and
* state factories, and for getting continuation contexts for
* supporting federation.
*<p>
* <tt>DirectoryManager</tt> is safe for concurrent access by multiple threads.
*<p>
* Except as otherwise noted,
* a <tt>Name</tt>, <tt>Attributes</tt>, 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
* @version 1.13 04/07/16
*
* @see DirObjectFactory
* @see DirStateFactory
* @since 1.3
*/
public class DirectoryManager extends NamingManager {
/*
* Disallow anyone from creating one of these.
*/
DirectoryManager() {}
/**
* Creates a context in which to continue a <tt>DirContext</tt> operation.
* Operates just like <tt>NamingManager.getContinuationContext()</tt>,
* only the continuation context returned is a <tt>DirContext</tt>.
*
* @param cpe
* The non-null exception that triggered this continuation.
* @return A non-null <tt>DirContext</tt> object for continuing the operation.
* @exception NamingException If a naming exception occurred.
*
* @see NamingManager#getContinuationContext(CannotProceedException)
*/
public static DirContext getContinuationDirContext(
CannotProceedException cpe) throws NamingException {
Hashtable env = cpe.getEnvironment();
if (env == null) {
env = new Hashtable(7);
} else {
// Make a (shallow) copy of the environment.
env = (Hashtable) env.clone();
}
env.put(CPE, cpe);
return (new ContinuationDirContext(cpe, env));
}
/**
* Creates an instance of an object for the specified object,
* attributes, and environment.
* <p>
* This method is the same as <tt>NamingManager.getObjectInstance</tt>
* except for the following differences:
*<ul>
*<li>
* It accepts an <tt>Attributes</tt> parameter that contains attributes
* associated with the object. The <tt>DirObjectFactory</tt> might use these
* attributes to save having to look them up from the directory.
*<li>
* The object factories tried must implement either
* <tt>ObjectFactory</tt> or <tt>DirObjectFactory</tt>.
* If it implements <tt>DirObjectFactory</tt>,
* <tt>DirObjectFactory.getObjectInstance()</tt> is used, otherwise,
* <tt>ObjectFactory.getObjectInstance()</tt> is used.
*</ul>
* Service providers that implement the <tt>DirContext</tt> interface
* should use this method, not <tt>NamingManager.getObjectInstance()</tt>.
*<p>
*
* @param refInfo The possibly null object for which to create an object.
* @param name The name of this object relative to <code>nameCtx</code>.
* Specifying a name is optional; if it is
* omitted, <code>name</code> should be null.
* @param nameCtx The context relative to which the <code>name</code>
* parameter is specified. If null, <code>name</code> 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.
* @param attrs The possibly null attributes associated with refInfo.
* This might not be the complete set of attributes for refInfo;
* you might be able to read more attributes from the directory.
* @return An object created using <code>refInfo</code> and <tt>attrs</tt>; or
* <code>refInfo</code> if an object cannot be created by
* a factory.
* @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 <tt>DirObjectFactory.getObjectInstance()</tt>.
* @see NamingManager#getURLContext
* @see DirObjectFactory
* @see DirObjectFactory#getObjectInstance
* @since 1.3
*/
public static Object
getObjectInstance(Object refInfo, Name name, Context nameCtx,
Hashtable<?,?> environment, Attributes attrs)
throws Exception {
ObjectFactory factory;
ObjectFactoryBuilder builder = getObjectFactoryBuilder();
if (builder != null) {
// builder must return non-null factory
factory = builder.createObjectFactory(refInfo, environment);
if (factory instanceof DirObjectFactory) {
return ((DirObjectFactory)factory).getObjectInstance(
refInfo, name, nameCtx, environment, attrs);
} else {
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 instanceof DirObjectFactory) {
return ((DirObjectFactory)factory).getObjectInstance(
ref, name, nameCtx, environment, attrs);
} else 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
// ignore name & attrs params; not used in URL factory
answer = processURLAddrs(ref, name, nameCtx, environment);
if (answer != null) {
return answer;
}
}
}
// try using any specified factories
answer = createObjectFromFactories(refInfo, name, nameCtx,
environment, attrs);
return (answer != null) ? answer : refInfo;
}
private static Object createObjectFromFactories(Object obj, Name name,
Context nameCtx, Hashtable environment, Attributes attrs)
throws Exception {
FactoryEnumeration factories = ResourceManager.getFactories(
Context.OBJECT_FACTORIES, environment, nameCtx);
if (factories == null)
return null;
ObjectFactory factory;
Object answer = null;
// Try each factory until one succeeds
while (answer == null && factories.hasMore()) {
factory = (ObjectFactory)factories.next();
if (factory instanceof DirObjectFactory) {
answer = ((DirObjectFactory)factory).
getObjectInstance(obj, name, nameCtx, environment, attrs);
} else {
answer =
factory.getObjectInstance(obj, name, nameCtx, environment);
}
}
return answer;
}
/**
* Retrieves the state of an object for binding when given the original
* object and its attributes.
* <p>
* This method is like <tt>NamingManager.getStateToBind</tt> except
* for the following differences:
*<ul>
*<li>It accepts an <tt>Attributes</tt> parameter containing attributes
* that were passed to the <tt>DirContext.bind()</tt> method.
*<li>It returns a non-null <tt>DirStateFactory.Result</tt> instance
* containing the object to be bound, and the attributes to
* accompany the binding. Either the object or the attributes may be null.
*<li>
* The state factories tried must each implement either
* <tt>StateFactory</tt> or <tt>DirStateFactory</tt>.
* If it implements <tt>DirStateFactory</tt>, then
* <tt>DirStateFactory.getStateToBind()</tt> is called; otherwise,
* <tt>StateFactory.getStateToBind()</tt> is called.
*</ul>
*
* Service providers that implement the <tt>DirContext</tt> interface
* should use this method, not <tt>NamingManager.getStateToBind()</tt>.
*<p>
* See NamingManager.getStateToBind() for a description of how
* the list of state factories to be tried is determined.
*<p>
* The object returned by this method is owned by the caller.
* The implementation will not subsequently modify it.
* It will contain either a new <tt>Attributes</tt> object that is
* likewise owned by the caller, or a reference to the original
* <tt>attrs</tt> parameter.
*
* @param obj The non-null object for which to get state to bind.
* @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 to
* be used in the creation of the state factory and
* the object's state.
* @param attrs The possibly null Attributes that is to be bound with the
* object.
* @return A non-null DirStateFactory.Result containing
* the object and attributes to be bound.
* If no state factory returns a non-null answer, the result will contain
* the object (<tt>obj</tt>) itself with the original attributes.
* @exception NamingException If a naming exception was encountered
* while using the factories.
* 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 <tt>DirStateFactory.getStateToBind()</tt>.
* @see DirStateFactory
* @see DirStateFactory#getStateToBind
* @see NamingManager#getStateToBind
* @since 1.3
*/
public static DirStateFactory.Result
getStateToBind(Object obj, Name name, Context nameCtx,
Hashtable<?,?> environment, Attributes attrs)
throws NamingException {
// Get list of state factories
FactoryEnumeration factories = ResourceManager.getFactories(
Context.STATE_FACTORIES, environment, nameCtx);
if (factories == null) {
// no factories to try; just return originals
return new DirStateFactory.Result(obj, attrs);
}
// Try each factory until one succeeds
StateFactory factory;
Object objanswer;
DirStateFactory.Result answer = null;
while (answer == null && factories.hasMore()) {
factory = (StateFactory)factories.next();
if (factory instanceof DirStateFactory) {
answer = ((DirStateFactory)factory).
getStateToBind(obj, name, nameCtx, environment, attrs);
} else {
objanswer =
factory.getStateToBind(obj, name, nameCtx, environment);
if (objanswer != null) {
answer = new DirStateFactory.Result(objanswer, attrs);
}
}
}
return (answer != null) ? answer :
new DirStateFactory.Result(obj, attrs); // nothing new
}
}
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