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 * 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

 * particular file as subject to the "Classpath" exception as provided

 *

 * 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.

 *

 */

package com.sun.corba.se.impl.presentation.rmi ;

import java.lang.reflect.Field ;

import java.util.Hashtable;

import javax.naming.*;

import javax.naming.spi.StateFactory;

import java.security.AccessController ;

import java.security.PrivilegedAction ;

import javax.rmi.PortableRemoteObject ;

import com.sun.corba.se.spi.orb.ORB;

import java.rmi.Remote;

import java.rmi.server.ExportException;

// XXX This creates a dependendcy on the implementation

// of the CosNaming service provider.

import com.sun.jndi.cosnaming.CNCtx ;

import com.sun.corba.se.spi.presentation.rmi.StubAdapter ;

/**

  * StateFactory that turns java.rmi.Remote objects to org.omg.CORBA.Object.

  * This version works either with standard RMI-IIOP or Dynamic RMI-IIOP.

  * Based on the original com.sun.jndi.cosnaming.RemoteToCorba and

  * com.sun.jndi.toolkit.corba.CorbaUtils.

  *

  * @author Ken Cavanaugh

  */

public class JNDIStateFactoryImpl implements StateFactory

{

    private static final Field orbField ;

    static {

        orbField = (Field) AccessController.doPrivileged(

            new PrivilegedAction() {

                public Object run() {

                    Field fld = null ;

                    try {

                        Class cls = CNCtx.class ;

                        fld = cls.getDeclaredField( "_orb" ) ;

                        fld.setAccessible( true ) ;

                    } catch (Exception exc) {

                        // XXX log exception at FINE

                    }

                    return fld ;

                }

            }

        ) ;

    }

    public JNDIStateFactoryImpl()

    {

    }

    /**

     * Returns the CORBA object for a Remote object.

     * If input is not a Remote object, or if Remote object uses JRMP, return null.

     * If the RMI-IIOP library is not available, throw ConfigurationException.

     *

     * @param orig The object to turn into a CORBA object. If not Remote,

     *             or if is a JRMP stub or impl, return null.

     * @param name Ignored

     * @param ctx The non-null CNCtx whose ORB to use.

     * @param env Ignored

     * @return The CORBA object for <tt>orig</tt> or null.

     * @exception ConfigurationException If the CORBA object cannot be obtained

     *    due to configuration problems

     * @exception NamingException If some other problem prevented a CORBA

     *    object from being obtained from the Remote object.

     */

    public Object getStateToBind(Object orig, Name name, Context ctx,

        Hashtable<?,?> env) throws NamingException

    {

        if (orig instanceof org.omg.CORBA.Object)

            return orig ;

        if (!(orig instanceof Remote))

            // Not for this StateFactory

            return null ;

        ORB orb = getORB( ctx ) ;

        if (orb == null)

            // Wrong kind of context, so just give up and let another StateFactory

            // try to satisfy getStateToBind.

            return null ;

        Remote stub = null;

        try {

            stub = PortableRemoteObject.toStub( (Remote)orig ) ;

        } catch (Exception exc) {

            // XXX log at FINE level?

            // Wrong sort of object: just return null to allow another StateFactory

            // to handle this.  This can happen easily because this StateFactory

            // is specified for the application, not the service context provider.

            return null ;

        }

        if (StubAdapter.isStub( stub )) {

            try {

                StubAdapter.connect( stub, orb ) ;

            } catch (Exception exc) {

                if (!(exc instanceof java.rmi.RemoteException)) {

                    // XXX log at FINE level?

                    // Wrong sort of object: just return null to allow another StateFactory

                    // to handle this call.

                    return null ;

                }

                // ignore RemoteException because stub might have already

                // been connected

            }

        }

        return stub ;

    }

    // This is necessary because the _orb field is package private in

    // com.sun.jndi.cosnaming.CNCtx.  This is not an ideal solution.

    // The best solution for our ORB is to change the CosNaming provider

    // to use the StubAdapter.  But this has problems as well, because

    // other vendors may use the CosNaming provider with a different ORB

    // entirely.

    private ORB getORB( Context ctx )

    {

        ORB orb = null ;

        try {

            orb = (ORB)orbField.get( ctx ) ;

        } catch (Exception exc) {

            // XXX log this exception at FINE level

            // ignore the exception and return null.

            // Note that the exception may be because ctx

            // is not a CosNaming context.

        }

        return orb ;

    }

}