gcc/libjava/javax/naming/spi/NamingManager.java

/* NamingManager.java --
   Copyright (C) 2000, 2001, 2002 Free Software Foundation, Inc.

This file is part of GNU Classpath.

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it under the terms of the GNU General Public License as published by
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permission to link this library with independent modules to produce an
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package javax.naming.spi;

import java.util.*;
import javax.naming.*;

public class NamingManager
{
  public static final String CPE = "java.naming.spi.CannotProceedException";

  private static InitialContextFactoryBuilder icfb = null;

  // Package private so DirectoryManager can access it.
  static ObjectFactoryBuilder ofb = null;

  // This class cannot be instantiated.
  NamingManager ()
  {
  }

  public static boolean hasInitialContextFactoryBuilder ()
  {
    return icfb != null;
  }
  
  public static Context getInitialContext (Hashtable environment)
    throws NamingException
  {
    InitialContextFactory icf = null;
    
    if (icfb != null)
      icf = icfb.createInitialContextFactory(environment);
    else
      {	 
	String java_naming_factory_initial = null;
	if (environment != null)
	  java_naming_factory_initial
	    = (String) environment.get (Context.INITIAL_CONTEXT_FACTORY);
	if (java_naming_factory_initial == null)
	  java_naming_factory_initial =
	    System.getProperty (Context.INITIAL_CONTEXT_FACTORY);
	if (java_naming_factory_initial == null)
	  throw new
	    NoInitialContextException ("Can't find property: "
				       + Context.INITIAL_CONTEXT_FACTORY);

	try
	  {
	    icf = (InitialContextFactory) Class.forName (java_naming_factory_initial).newInstance ();
	  }
	catch (Exception exception)
	  {
	    NoInitialContextException e
	      = new NoInitialContextException ("Can't load InitialContextFactory class: "
					       + java_naming_factory_initial);
	    e.setRootCause(exception);
	    throw e;
	  }
      }

    return icf.getInitialContext (environment);
  }

  static Context getURLContext (Object refInfo,
				Name name,
				Context nameCtx,
				String scheme,
				Hashtable environment) 
    throws NamingException
  {
    String prefixes = null;
    if (environment != null)
      prefixes = (String) environment.get (Context.URL_PKG_PREFIXES);
    if (prefixes == null)
      prefixes = System.getProperty (Context.URL_PKG_PREFIXES);
    if (prefixes == null)
      {
	// Specified as the default in the docs.  Unclear if this is
	// right for us.
	prefixes = "com.sun.jndi.url";
      }

    scheme += "URLContextFactory";

    StringTokenizer tokens = new StringTokenizer (prefixes, ":");
    while (tokens.hasMoreTokens ())
      {
	String aTry = tokens.nextToken ();
	try
	  {
	    Class factoryClass = Class.forName (aTry + "." + scheme);
	    ObjectFactory factory =
	      (ObjectFactory) factoryClass.newInstance ();
	    Object obj = factory.getObjectInstance (refInfo, name,
						    nameCtx, environment);
	    Context ctx = (Context) obj;
	    if (ctx != null)
	      return ctx;
	  }
	catch (ClassNotFoundException _1)
	  {
	    // Ignore it.
	  }
	catch (ClassCastException _2)
	  {
	    // This means that the class we found was not an
	    // ObjectFactory or that the factory returned something
	    // which was not a Context.
	  }
	catch (InstantiationException _3)
	  {
	    // If we couldn't instantiate the factory we might get
	    // this.
	  }
	catch (IllegalAccessException _4)
	  {
	    // Another possibility when instantiating.
	  }
	catch (NamingException _5)
	  {
	    throw _5;
	  }
	catch (Exception _6)
	  {
	    // Anything from getObjectInstance.
	  }
      }

    return null;
  }

  public static Context getURLContext (String scheme,
				       Hashtable environment) 
       throws NamingException
  {
    return getURLContext (null, null, null, scheme, environment);
  }

  public static void setObjectFactoryBuilder (ObjectFactoryBuilder builder)
    throws NamingException
  {
    SecurityManager sm = System.getSecurityManager ();
    if (sm != null)
      sm.checkSetFactory ();
    // Once the builder is installed it cannot be replaced.
    if (ofb != null)
      throw new IllegalStateException ("builder already installed");
    if (builder != null)
      ofb = builder;
  }

  static StringTokenizer getPlusPath (String property, Hashtable env,
				      Context nameCtx)
    throws NamingException
  {
    String path = (String) env.get (property);
    if (nameCtx == null)
      nameCtx = getInitialContext (env);
    String path2 = (String) nameCtx.getEnvironment ().get (property);
    if (path == null)
      path = path2;
    else if (path2 != null)
      path += ":" + path2;
    return new StringTokenizer (path != null ? path : "", ":");
  }

  public static Object getObjectInstance (Object refInfo,
					  Name name,
					  Context nameCtx,
					  Hashtable environment)
    throws Exception
  {
    ObjectFactory factory = null;

    if (ofb != null)
      factory = ofb.createObjectFactory (refInfo, environment);
    else
      {
	// First see if we have a Reference or a Referenceable.  If so
	// we do some special processing.
	Object ref2 = refInfo;
	if (refInfo instanceof Referenceable)
	  ref2 = ((Referenceable) refInfo).getReference ();
	if (ref2 instanceof Reference)
	  {
	    Reference ref = (Reference) ref2;

	    // If we have a factory class name then we use that.
	    String fClass = ref.getFactoryClassName ();
	    if (fClass != null)
	      {
		// Exceptions here are passed to the caller.
		Class k = Class.forName (fClass);
		factory = (ObjectFactory) k.newInstance ();
	      }
	    else
	      {
		// There's no factory class name.  If the address is a
		// StringRefAddr with address type `URL', then we try
		// the URL's context factory.
		Enumeration e = ref.getAll ();
		while (e.hasMoreElements ())
		  {
		    RefAddr ra = (RefAddr) e.nextElement ();
		    if (ra instanceof StringRefAddr
			&& "URL".equals (ra.getType ()))
		      {
			factory
			  = (ObjectFactory) getURLContext (refInfo,
							   name,
							   nameCtx,
							   (String) ra.getContent (),
							   environment);
			Object obj = factory.getObjectInstance (refInfo,
								name,
								nameCtx,
								environment);
			if (obj != null)
			  return obj;
		      }
		  }

		// Have to try the next step.
		factory = null;
	      }
	  }

	// Now look at OBJECT_FACTORIES to find the factory.
	if (factory == null)
	  {
	    StringTokenizer tokens = getPlusPath (Context.OBJECT_FACTORIES,
						  environment, nameCtx);

	    while (tokens.hasMoreTokens ())
	      {
		String klassName = tokens.nextToken ();
		Class k = Class.forName (klassName);
		factory = (ObjectFactory) k.newInstance ();
		Object obj = factory.getObjectInstance (refInfo, name,
							nameCtx, environment);
		if (obj != null)
		  return obj;
	      }

	    // Failure.
	    return refInfo;
	  }
      }

    if (factory == null)
      return refInfo;
    Object obj = factory.getObjectInstance (refInfo, name,
					    nameCtx, environment);
    return obj == null ? refInfo : obj;
  }

  public static void setInitialContextFactoryBuilder (InitialContextFactoryBuilder builder)
    throws NamingException
  {
    SecurityManager sm = System.getSecurityManager ();
    if (sm != null)
      sm.checkSetFactory ();
    // Once the builder is installed it cannot be replaced.
    if (icfb != null)
      throw new IllegalStateException ("builder already installed");
    if (builder != null)
      icfb = builder;
  }

  public static Context getContinuationContext (CannotProceedException cpe)
    throws NamingException
  {
    Hashtable env = cpe.getEnvironment ();
    if (env != null)
      env.put (CPE, cpe);

    // It is really unclear to me if this is right.
    try
      {
	Object obj = getObjectInstance (null, cpe.getAltName (),
					cpe.getAltNameCtx (), env);
	if (obj != null)
	  return (Context) obj;
      }
    catch (Exception _)
      {
      }

    throw cpe;
  }

  public static Object getStateToBind (Object obj, Name name,
				       Context nameCtx, Hashtable environment)
    throws NamingException
  {
    StringTokenizer tokens = getPlusPath (Context.STATE_FACTORIES,
					  environment, nameCtx);
    while (tokens.hasMoreTokens ())
      {
	String klassName = tokens.nextToken ();
	try
	  {
	    Class k = Class.forName (klassName);
	    StateFactory factory = (StateFactory) k.newInstance ();
	    Object o = factory.getStateToBind (obj, name, nameCtx,
					       environment);
	    if (o != null)
	      return o;
	  }
	catch (ClassNotFoundException _1)
	  {
	    // Ignore it.
	  }
	catch (ClassCastException _2)
	  {
	    // This means that the class we found was not an
	    // ObjectFactory or that the factory returned something
	    // which was not a Context.
	  }
	catch (InstantiationException _3)
	  {
	    // If we couldn't instantiate the factory we might get
	    // this.
	  }
	catch (IllegalAccessException _4)
	  {
	    // Another possibility when instantiating.
	  }
      }

    return obj;
  }
}