old-autovect-branch/libjava/classpath/javax/rmi/CORBA/PortableRemoteObjectDelegate.java

   1 /* PortableRemoteObjectDelegate.java -- Interface supporting PortableRemoteObject
   2    Copyright (C) 2002, 2004, 2005 Free Software Foundation, Inc.
   3
   4 This file is part of GNU Classpath.
   5
   6 GNU Classpath is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Classpath is distributed in the hope that it will be useful, but
  12 WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Classpath; see the file COPYING.  If not, write to the
  18 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19 02110-1301 USA.
  20
  21 Linking this library statically or dynamically with other modules is
  22 making a combined work based on this library.  Thus, the terms and
  23 conditions of the GNU General Public License cover the whole
  24 combination.
  25
  26 As a special exception, the copyright holders of this library give you
  27 permission to link this library with independent modules to produce an
  28 executable, regardless of the license terms of these independent
  29 modules, and to copy and distribute the resulting executable under
  30 terms of your choice, provided that you also meet, for each linked
  31 independent module, the terms and conditions of the license of that
  32 module.  An independent module is a module which is not derived from
  33 or based on this library.  If you modify this library, you may extend
  34 this exception to your version of the library, but you are not
  35 obligated to do so.  If you do not wish to do so, delete this
  36 exception statement from your version. */
  37
  38
  39 package javax.rmi.CORBA;
  40
  41 import java.rmi.NoSuchObjectException;
  42 import java.rmi.Remote;
  43 import java.rmi.RemoteException;
  44
  45 /**
  46  * A delegate, implementing the functionality, provided by the
  47  * {@link PortableRemoteObject}.
  48  *
  49  * The default delegate can be altered by setting the system property
  50  * "javax.rmi.CORBA.PortableRemoteObjectClass" to the name of the alternative
  51  * class that must implement {@link PortableRemoteObjectDelegate}.
  52  *
  53  * @author Audrius Meskauskas (AudriusA@Bioinformatics.org)
  54  */
  55 public interface PortableRemoteObjectDelegate
  56 {
  57   /**
  58    * <p>
  59    * Makes the remote object <code>target</code> ready for remote
  60    * communication using the same communications runtime as for the passed
  61    * <code>source</code> parameter. Connection normally happens implicitly
  62    * when the object is sent or received as an argument on a remote method call.
  63    * </p>
  64    * <p>
  65    * The target object is connected to the same ORB as source by calling the
  66    * {@link Stub#connect} if it is a stub or by associating its tie with an ORB
  67    * if it is an implementation object.
  68    * </p>
  69    *
  70    * @param target the target object that may be either an RMI/IDL stub or an
  71    * exported RMI/IDL implementation object
  72    * @param source the source object may also be either an RMI/IDL stub or an
  73    * exported RMI/IDL implementation object.
  74    *
  75    * @throws RemoteException if the target is already connected to another ORB.
  76    */
  77   void connect(Remote target, Remote source)
  78     throws RemoteException;
  79
  80   /**
  81    * Register the passed object with the ORB runtimes, making it remotely
  82    * accessible. When called on jre with no objects exported, creates a
  83    * non-daemon thread that prevents jre from terminating until all objects are
  84    * unexported. Also, such object cannot be collected by garbage collector.
  85    * This is usually impemented via {@link Util#unexportObject}
  86    *
  87    * @param object the object to export.
  88    *
  89    * @throws RemoteException
  90    */
  91   void exportObject(Remote obj)
  92     throws RemoteException;
  93
  94   /**
  95    * Narrows the passed object to conform to the given interface or IDL type.
  96    * This method may return different instance and cannot be replaced by the
  97    * direct cast.
  98    *
  99    * @param narrowFrom an object to narrow.
 100    * @param narrowTo a type to that the object must be narrowed.
 101    *
 102    * @return On success, an object of type narrowTo or null, if narrowFrom =
 103    * null.
 104    *
 105    * @throws ClassCastException if no narrowing is possible.
 106    */
 107   Object narrow(Object narrowFrom, Class narrowTo)
 108     throws ClassCastException;
 109
 110   /**
 111    * Takes a server implementation object and returns a stub object that can be
 112    * used to access that server object (target). If the target is connected, the
 113    * returned stub is also connected to the same ORB. If the target is
 114    * unconnected, the returned stub is unconnected.
 115    *
 116    * @param target a server side object.
 117    * @return a stub object that can be used to access that server object.
 118    *
 119    * @throws NoSuchObjectException if a stub cannot be located for the given
 120    * target.
 121    */
 122   Remote toStub(Remote obj)
 123     throws NoSuchObjectException;
 124
 125   /**
 126    * Deregister a currently exported server object from the ORB runtimes. The
 127    * object to becomes available for garbage collection. This is usually
 128    * impemented via {@link Util#unexportObject}
 129    *
 130    * @param object the object to unexport.
 131    *
 132    * @throws NoSuchObjectException if the passed object is not currently
 133    * exported.
 134    */
 135   void unexportObject(Remote obj)
 136     throws NoSuchObjectException;
 137 }