activatable.java

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   *         inactivated because of the running or pending calls.
   * @throws UnknownObjectException if the object is unknown.
   * @throws ActivationException if the object group is not active
   * @throws RemoteException if the remote call fails
   */
  public static boolean inactive(ActivationID id)
      throws UnknownObjectException, ActivationException, RemoteException
  {
    if (id.group!=null)
      id.group.inactiveObject(id);
    return UnicastRemoteObject.unexportObject(id.activate(false), false);
  }
  
  /**
   * Unregister the object (the object will no longer be activable with that id)
   * 
   * @param id the object id
   * @throws UnknownObjectException if the id is unknown
   * @throws ActivationException if the activation system is not running
   * @throws RemoteException if the remote call fails.
   */
  public static void unregister(ActivationID id) throws UnknownObjectException,
      ActivationException, RemoteException
  {
    ActivationGroup.currentGroupId.getSystem().unregisterObject(id);
    UnicastServer.unregisterActivatable(id);
  }
  
  /**
   * Register and export the object that activatable object that is not derived
   * from the Activatable super class. It creates and registers the object
   * activation descriptor. There is no need to call this method if the object
   * extends Activable, as its work is done in the constructor
   * {@link #Activatable(String, MarshalledObject, boolean, int)}.
   * 
   * @param obj the object, that is exported, becoming available at the given
   *          port.
   * @param location the object code location (codebase).
   * @param data the data, needed to activate the object
   * @param restart the restart mode
   * @param port the port, where the object will be available
   * 
   * @return the created object activation ID.
   * 
   * @throws ActivationException if the activation group is not active
   * @throws RemoteException if the registration or export fails
   */
  public static ActivationID exportObject(Remote obj, String location,
                                          MarshalledObject data,
                                          boolean restart, int port)
      throws ActivationException, RemoteException
  {
    ActivationDesc descriptor = new ActivationDesc(obj.getClass().getName(),
                                                   location, data, restart);
    ActivationID id = obtainId(descriptor);
    Remote stub = exportObject(obj, id, port);    
    return id;
  }

  /**
   * Register and export the object that activatable object that is not derived
   * from the Activatable super class. It creates and registers the object
   * activation descriptor. There is no need to call this method if the object
   * extends Activable, as its work is done in the constructor
   * {@link #Activatable(String, MarshalledObject, boolean, int, RMIClientSocketFactory, RMIServerSocketFactory)}
   * 
   * @param obj the object, that is exported, becoming available at the given
   *          port.
   * @param location the object code location (codebase).
   * @param data the data, needed to activate the object
   * @param restart the restart mode
   * @param port the port, where the object will be available
   * @param csf the client socket factory
   * @param ssf the server socket factory
   * 
   * @return the created object activation ID.
   * 
   * @throws ActivationException if the activation group is not active
   * @throws RemoteException if the registration or export fails
   */
  public static ActivationID exportObject(Remote obj, String location,
                                          MarshalledObject data,
                                          boolean restart, int port,
                                          RMIClientSocketFactory csf,
                                          RMIServerSocketFactory ssf)
      throws ActivationException, RemoteException
  {
    ActivationDesc descriptor = new ActivationDesc(obj.getClass().getName(),
                                                   location, data, restart);
    ActivationID id = obtainId(descriptor);
    Remote stub = exportObject(obj, id, port, csf, ssf);    
    return id;

  }

  /**
   * During activation, this exportObject method should be invoked explicitly by
   * the activatable object, that does is not derived from the Activatable
   * class. There is no need to call this method if the object extends
   * Activable, as its work is done in the constructor
   * {@link #Activatable(ActivationID, int)}
   * 
   * @param obj the object
   * @param id the known activation id
   * @param port the object port
   *  
   * @return the remote stub of the activatable object
   * 
   * @throws RemoteException if the object export fails
   */
  public static Remote exportObject(Remote obj, ActivationID id, int port)
      throws RemoteException
  {
    Remote stub = export(id, obj, port, null);
    return stub;
  }

  /**
   * During activation, this exportObject method should be invoked explicitly by
   * the activatable object, that does is not derived from the Activatable
   * class. There is no need to call this method if the object extends
   * Activable, as its work is done in the constructor
   * {@link #Activatable(ActivationID, int)}
   * 
   * @param obj the object
   * @param id the known activation id
   * @param port the object port
   * @param csf the client socket factory
   * @param ssf the server socket factory
   *  
   * @return the remote stub of the activatable object
   * 
   * @throws RemoteException if the object export fails
   */
  public static Remote exportObject(Remote obj, ActivationID id, int port,
                                    RMIClientSocketFactory csf,
                                    RMIServerSocketFactory ssf)
      throws RemoteException
  {
    Remote stub = export(id, obj, port, ssf); 
    return stub;

  }

  /**
   * Make the remote object unavailable for incoming calls. This method also
   * unregisters the object, so it cannot be activated again by incomming call
   * (unless registered).
   * 
   * @param obj the object to unexport
   * @param force if true, cancel all pending or running calls to that object
   *          (if false, the object with such calls is not unexported and false
   *          is returned by this method).
   * @return if the object was successfully unexported, false otherwise
   * @throws NoSuchObjectException if such object is not known
   */
  public static boolean unexportObject(Remote obj, boolean force)
      throws NoSuchObjectException
  {
    Object aref = UnicastServer.getExportedRef(obj);
    
    // Unregister it also (otherwise will be activated during the subsequent
    // call.
    if (aref instanceof ActivatableServerRef)
      {
        ActivatableServerRef aar = (ActivatableServerRef) aref;
        UnicastServer.unregisterActivatable(aar.actId);
      }
    return UnicastRemoteObject.unexportObject(obj, force);
  }
  
  static Remote exportObject(Remote obj, int port, 
                             RMIServerSocketFactory serverSocketFactory) 
    throws RemoteException
  {
    UnicastServerRef sref = null;
    if (obj instanceof RemoteObject)
      sref = (UnicastServerRef) ((RemoteObject) obj).getRef();

    if (sref == null)
      sref = new UnicastServerRef(new ObjID(), port, serverSocketFactory);

    Remote stub = sref.exportObject(obj);
    // addStub(obj, stub); 
    // TODO Need to change the place of the stub repository
    return stub;
  }
  
  /**
   * Create and export the new remote object, making it available at the given
   * port, using sockets, produced by the specified factories.
   * 
   * @param port the port, on that the object should become available. Zero
   *          means anonymous port.
   * @param serverSocketFactory the server socket factory
   */
  public static Remote export(ActivationID id, Remote obj, int port,
                              RMIServerSocketFactory serverSocketFactory)
      throws RemoteException
  {
    UnicastServerRef sref = null;
    if (obj instanceof RemoteObject)
      sref = (UnicastServerRef) ((RemoteObject) obj).getRef();

    if (sref == null)
      sref = new ActivatableServerRef(makeId(id), id, port, serverSocketFactory);

    Remote stub = sref.exportObject(obj);
    // addStub(obj, stub); // need probably the stub repository elsewhere
    return stub;
  }  
  
  /**
   * Make the object ID from the activation ID. The same activation ID always
   * produces the identical object id.
   * 
   * @param aid the activation id
   * 
   * @return the object id
   */
  public static ObjID makeId(ActivationID aid)
  {
    ObjID id = new ObjID(0);
    
    // The fields of both ObjID and ActivationID must be package private,
    // so we need to use the reflection to access them anyway.
    // Probably other implementations use some very different approach.
    
    try
      {
        Field idUid =  ObjID.class.getDeclaredField("space");
        Field aidUid = ActivationID.class.getDeclaredField("uid");
        
        aidUid.setAccessible(true);
        idUid.setAccessible(true);
        
        idUid.set(id, aidUid.get(aid));
      }
    catch (Exception e)
      {
        InternalError ierr = new InternalError("Unable to set UID field");
        ierr.initCause(e);
        throw ierr;
      }
    
    return id;
  }  
  
}