/*
* @(#)PortableRemoteObject.java 1.13 04/06/21
*
* Copyright 2004 Sun Microsystems, Inc. All rights reserved.
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*/
/*
* Licensed Materials - Property of IBM
* RMI-IIOP v1.0
* Copyright IBM Corp. 1998 1999 All Rights Reserved
*
* US Government Users Restricted Rights - Use, duplication or
* disclosure restricted by GSA ADP Schedule Contract with IBM Corp.
*/
package com.sun.corba.se.impl.javax.rmi;
import java.lang.reflect.Method ;
import javax.rmi.CORBA.Tie;
import javax.rmi.CORBA.Util;
import java.rmi.RemoteException;
import java.rmi.NoSuchObjectException;
import java.rmi.Remote;
import java.util.Properties;
import org.omg.CORBA.ORB;
import org.omg.CORBA.portable.Delegate;
import org.omg.CORBA.SystemException;
import java.rmi.server.UnicastRemoteObject;
import java.rmi.server.RemoteStub;
import java.rmi.server.ExportException;
import java.net.URL;
import com.sun.corba.se.impl.util.JDKBridge;
import com.sun.corba.se.impl.util.Utility;
import com.sun.corba.se.impl.util.RepositoryId;
import com.sun.corba.se.spi.presentation.rmi.StubAdapter;
import java.security.AccessController;
import com.sun.corba.se.impl.orbutil.GetPropertyAction;
/**
* Server implementation objects may either inherit from
* javax.rmi.PortableRemoteObject or they may implement a remote interface
* and then use the exportObject method to register themselves as a server object.
* The toStub method takes a server implementation and returns a stub that
* can be used to access that server object.
* The connect method makes a Remote object ready for remote communication.
* The unexportObject method is used to deregister a server object, allowing it to become
* available for garbage collection.
* The narrow method takes an object reference or abstract interface type and
* attempts to narrow it to conform to
* the given interface. If the operation is successful the result will be an
* object of the specified type, otherwise an exception will be thrown.
*/
public class PortableRemoteObject
implements javax.rmi.CORBA.PortableRemoteObjectDelegate {
/**
* Makes a server object ready to receive remote calls. Note
* that subclasses of PortableRemoteObject do not need to call this
* method, as it is called by the constructor.
* @param obj the server object to export.
* @exception RemoteException if export fails.
*/
public void exportObject(Remote obj)
throws RemoteException {
if (obj == null) {
throw new NullPointerException("invalid argument");
}
// Has this object already been exported to IIOP?
if (Util.getTie(obj) != null) {
// Yes, so this is an error...
throw new ExportException (obj.getClass().getName() + " already exported");
}
// Can we load a Tie?
Tie theTie = Utility.loadTie(obj);
if (theTie != null) {
// Yes, so export it to IIOP...
Util.registerTarget(theTie,obj);
} else {
// No, so export to JRMP. If this is called twice for the
// same object, it will throw an ExportException...
UnicastRemoteObject.exportObject(obj);
}
}
/**
* Returns a stub for the given server object.
* @param obj the server object for which a stub is required. Must either be a subclass
* of PortableRemoteObject or have been previously the target of a call to
* {@link #exportObject}.
* @return the most derived stub for the object.
* @exception NoSuchObjectException if a stub cannot be located for the given server object.
*/
public Remote toStub (Remote obj)
throws NoSuchObjectException
{
Remote result = null;
if (obj == null) {
throw new NullPointerException("invalid argument");
}
// If the class is already an IIOP stub then return it.
if (StubAdapter.isStub( obj )) {
return obj;
}
// If the class is already a JRMP stub then return it.
if (obj instanceof java.rmi.server.RemoteStub) {
return obj;
}
// Has it been exported to IIOP?
Tie theTie = Util.getTie(obj);
if (theTie != null) {
result = Utility.loadStub(theTie,null,null,true);
} else {
if (Utility.loadTie(obj) == null) {
result = java.rmi.server.RemoteObject.toStub(obj);
}
}
if (result == null) {
throw new NoSuchObjectException("object not exported");
}
return result;
}
/**
* Deregisters a server object from the runtime, allowing the object to become
* available for garbage collection.
* @param obj the object to unexport.
* @exception NoSuchObjectException if the remote object is not
* currently exported.
*/
public void unexportObject(Remote obj)
throws NoSuchObjectException {
if (obj == null) {
throw new NullPointerException("invalid argument");
}
if (StubAdapter.isStub(obj) ||
obj instanceof java.rmi.server.RemoteStub) {
throw new NoSuchObjectException(
"Can only unexport a server object.");
}
Tie theTie = Util.getTie(obj);
if (theTie != null) {
Util.unexportObject(obj);
} else {
if (Utility.loadTie(obj) == null) {
UnicastRemoteObject.unexportObject(obj,true);
} else {
throw new NoSuchObjectException("Object not exported.");
}
}
}
/**
* Checks to ensure that an object of a remote or abstract interface type
* can be cast to a desired type.
* @param narrowFrom the object to check.
* @param narrowTo the desired type.
* @return an object which can be cast to the desired type.
* @throws ClassCastException if narrowFrom cannot be cast to narrowTo.
*/
public java.lang.Object narrow ( java.lang.Object narrowFrom,
java.lang.Class narrowTo) throws ClassCastException
{
java.lang.Object result = null;
if (narrowFrom == null)
return null;
if (narrowTo == null)
throw new NullPointerException("invalid argument");
try {
if (narrowTo.isAssignableFrom(narrowFrom.getClass()))
return narrowFrom;
// Is narrowTo an interface that might be
// implemented by a servant running on iiop?
if (narrowTo.isInterface() &&
narrowTo != java.io.Serializable.class &&
narrowTo != java.io.Externalizable.class) {
org.omg.CORBA.Object narrowObj
= (org.omg.CORBA.Object) narrowFrom;
// Create an id from the narrowTo type...
String id = RepositoryId.createForAnyType(narrowTo);
if (narrowObj._is_a(id)) {
return Utility.loadStub(narrowObj,narrowTo);
} else {
throw new ClassCastException( "Object is not of remote type " +
narrowTo.getName() ) ;
}
} else {
throw new ClassCastException( "Class " + narrowTo.getName() +
" is not a valid remote interface" ) ;
}
} catch(Exception error) {
ClassCastException cce = new ClassCastException() ;
cce.initCause( error ) ;
throw cce ;
}
}
/**
* Makes a Remote object ready for remote communication. This normally
* happens implicitly when the object is sent or received as an argument
* on a remote method call, but in some circumstances it is useful to
* perform this action by making an explicit call. See the
* {@link Stub#connect} method for more information.
* @param target the object to connect.
* @param source a previously connected object.
* @throws RemoteException if <code>source</code> is not connected
* or if <code>target</code> is already connected to a different ORB than
* <code>source</code>.
*/
public void connect (Remote target, Remote source)
throws RemoteException
{
if (target == null || source == null) {
throw new NullPointerException("invalid argument");
}
ORB orb = null;
try {
if (StubAdapter.isStub( source )) {
orb = StubAdapter.getORB( source ) ;
} else {
// Is this a servant that was exported to iiop?
Tie tie = Util.getTie(source);
if (tie == null) {
/* loadTie always succeeds for dynamic RMI-IIOP
// No, can we get a tie for it? If not,
// assume that source is a JRMP object...
if (Utility.loadTie(source) != null) {
// Yes, so it is an iiop object which
// has not been exported...
throw new RemoteException(
"'source' object not exported");
}
*/
} else {
orb = tie.orb();
}
}
} catch (SystemException e) {
throw new RemoteException("'source' object not connected", e );
}
boolean targetIsIIOP = false ;
Tie targetTie = null;
if (StubAdapter.isStub(target)) {
targetIsIIOP = true;
} else {
targetTie = Util.getTie(target);
if (targetTie != null) {
targetIsIIOP = true;
} else {
/* loadTie always succeeds for dynamic RMI-IIOP
if (Utility.loadTie(target) != null) {
throw new RemoteException("'target' servant not exported");
}
*/
}
}
if (!targetIsIIOP) {
// Yes. Do we have an ORB from the source object?
// If not, we're done - there is nothing to do to
// connect a JRMP object. If so, it is an error because
// the caller mixed JRMP and IIOP...
if (orb != null) {
throw new RemoteException(
"'source' object exported to IIOP, 'target' is JRMP");
}
} else {
// The target object is IIOP. Make sure we have a
// valid ORB from the source object...
if (orb == null) {
throw new RemoteException(
"'source' object is JRMP, 'target' is IIOP");
}
// And, finally, connect it up...
try {
if (targetTie != null) {
// Is the tie already connected?
try {
ORB existingOrb = targetTie.orb();
// Yes. Is it the same orb?
if (existingOrb == orb) {
// Yes, so nothing to do...
return;
} else {
// No, so this is an error...
throw new RemoteException(
"'target' object was already connected");
}
} catch (SystemException e) {}
// No, so do it...
targetTie.orb(orb);
} else {
StubAdapter.connect( target, orb ) ;
}
} catch (SystemException e) {
// The stub or tie was already connected...
throw new RemoteException(
"'target' object was already connected", e );
}
}
}
}
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