net.jini.activation
Class ActivationGroup

java.lang.Object
  java.rmi.server.RemoteObject
      java.rmi.server.RemoteServer
          java.rmi.server.UnicastRemoteObject
              java.rmi.activation.ActivationGroup
                  net.jini.activation.ActivationGroup

All Implemented Interfaces:

Serializable, ActivationInstantiator, Remote

public abstract class ActivationGroup
extends ActivationGroup

Subclass of java.rmi.activation.ActivationGroup to allow activatable objects that are exported using an Exporter to go inactive.

This class can be used only productively in conjunction with an activation system daemon implementation that will cause the createGroup method of this class to be called. The standard rmid does not do this.

Since:

2.0

Author:

Sun Microsystems, Inc.

See Also:

Serialized Form

Field Summary

Fields inherited from class java.rmi.server.RemoteObject

ref

Constructor Summary

protected

ActivationGroup(ActivationGroupID id) Constructs an activation group with the specified activation group identifier.

Method Summary

static ActivationGroup	createGroup(ActivationGroupID id, ActivationGroupDesc desc, long incarnation) Creates and sets the activation group for the current virtual machine.
static boolean	inactive(ActivationID id, Exporter exporter) Attempts to make the remote object that is associated with the specified activation identifier, and that was exported through the specified exporter, inactive.
abstract boolean	inactiveObject(ActivationID id, Exporter exporter) Attempts to make the remote object that is associated with the specified activation identifier, and that was exported through the specified exporter, inactive.

Methods inherited from class java.rmi.activation.ActivationGroup

activeObject, activeObject, currentGroupID, getSystem, inactiveGroup, inactiveObject, setSystem

Methods inherited from class java.rmi.server.UnicastRemoteObject

clone, exportObject, exportObject, exportObject, unexportObject

Methods inherited from class java.rmi.server.RemoteServer

getClientHost, getLog, setLog

Methods inherited from class java.rmi.server.RemoteObject

equals, getRef, hashCode, toString, toStub

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.rmi.activation.ActivationInstantiator

newInstance

Constructor Detail

ActivationGroup

protected ActivationGroup(ActivationGroupID id)
                   throws RemoteException

Constructs an activation group with the specified activation group identifier. This constructor exports the group as a UnicastRemoteObject. A subclass constructor can, if desired, unexport the group and then re-export it a different way.

Parameters:

id - the activation group identifier

Throws:

RemoteException - if this group could not be exported

Method Detail

createGroup

public static ActivationGroup createGroup(ActivationGroupID id,
                                          ActivationGroupDesc desc,
                                          long incarnation)
                                   throws ActivationException

Creates and sets the activation group for the current virtual machine. This method calls java.rmi.activation.ActivationGroup.createGroup with the same arguments, and returns the result. This method must be called in order to use the inactive method of this class.

Parameters:

id - the activation group identifier

desc - the activation group descriptor

incarnation - the group incarnation number (zero on initial creation)

Returns:

the created activation group

Throws:

ActivationException - if a group already exists, if the group's class is not a subclass of this class, or if an exception occurs creating the group

SecurityException - if a security manager exists and invoking its checkSetFactory method throws a SecurityException

inactive

public static boolean inactive(ActivationID id,
                               Exporter exporter)
                        throws ActivationException,
                               RemoteException

Attempts to make the remote object that is associated with the specified activation identifier, and that was exported through the specified exporter, inactive. This method calls the inactiveObject method of the current group with the same arguments, and returns the result. The overall effect is as follows. The unexport method of the specified exporter is called with false as an argument. If that call returns false, this method returns false. If that call returns true, the object is marked inactive in this virtual machine, the ActivationMonitor.inactiveObject method of the group's monitor is called to inform the activation system daemon that the object is inactive, and this method returns true.

Parameters:

id - the object's activation identifier

exporter - the exporter to use to unexport the object

Returns:

true if the object was successfully made inactive; false otherwise

Throws:

UnknownObjectException - if the object is not known to be active (it may already be inactive)

ActivationException - if the group is not active

RemoteException - if the remote call to the activation monitor fails

inactiveObject

public abstract boolean inactiveObject(ActivationID id,
                                       Exporter exporter)
                                throws ActivationException,
                                       RemoteException

Attempts to make the remote object that is associated with the specified activation identifier, and that was exported through the specified exporter, inactive. The unexport method of the specified exporter is called with false as an argument. If that call returns false, this method returns false. If that call returns true, the object is marked inactive in this virtual machine, the ActivationMonitor.inactiveObject method of the group's monitor is called to inform the activation system daemon that the object is inactive, and this method returns true.

Parameters:

id - the object's activation identifier

exporter - the exporter to use to unexport the object

Returns:

true if the object was successfully made inactive; false otherwise

Throws:

UnknownObjectException - if the object is not known to be active (it may already be inactive)

ActivationException - if the group is not active

RemoteException - if the remote call to the activation monitor fails