java.rmi.activation
Interface ActivationSystem

public abstract interface ActivationSystem

extends Remote

The ActivationSystem provides a means for registering groups and "activatable" objects to be activated within those groups. The ActivationSystem works closely with the Activator, which activates objects registered via the ActivationSystem, and the ActivationMonitor, which obtains information about active and inactive objects, and inactive groups.

Since:

JDK1.2

See Also:

Activator, ActivationMonitor

Field Summary

static int

SYSTEM_PORT The port to lookup the activation system

Method Summary

ActivationMonitor	activeGroup(ActivationGroupID id, ActivationInstantiator group, long incarnation) Callback to inform activation system that group is now active.
ActivationDesc	getActivationDesc(ActivationID id) Returns the activation descriptor, for the object with the activation identifier, id.
ActivationGroupDesc	getActivationGroupDesc(ActivationGroupID id) Returns the activation group descriptor, for the group with the activation group identifier, id.
ActivationGroupID	registerGroup(ActivationGroupDesc desc) Register the activation group.
ActivationID	registerObject(ActivationDesc desc) The registerObject method is used to register an activation descriptor, desc, and obtain an activation identifier for a activatable remote object.
ActivationDesc	setActivationDesc(ActivationID id, ActivationDesc desc) Set the activation descriptor, desc for the object with the activation identifier, id.
ActivationGroupDesc	setActivationGroupDesc(ActivationGroupID id, ActivationGroupDesc desc) Set the activation group descriptor, desc for the object with the activation group identifier, id.
void	shutdown() Shutdown the activation system.
void	unregisterGroup(ActivationGroupID id) Remove the activation group.
void	unregisterObject(ActivationID id) Remove the activation id and associated descriptor previously registered with the ActivationSystem; the object can no longer be activated via the object's activation id.

Field Detail

SYSTEM_PORT

public static final int SYSTEM_PORT

The port to lookup the activation system

Method Detail

registerObject

public ActivationID registerObject(ActivationDesc desc)
                            throws ActivationException,
                                   UnknownGroupException,
                                   RemoteException

The registerObject method is used to register an activation descriptor, desc, and obtain an activation identifier for a activatable remote object. The ActivationSystem creates an ActivationID (a activation identifier) for the object specified by the descriptor, desc, and records, in stable storage, the activation descriptor and its associated identifier for later use. When the Activator receives an activate request for a specific identifier, it looks up the activation descriptor (registered previously) for the specified identifier and uses that information to activate the object.

Parameters:

desc - the object's activation descriptor

Returns:

the activation id that can be used to activate the object

Throws:

ActivationException - if registration fails (e.g., database update failure, etc).

UnknownGroupException - if group referred to in desc is not registered with this system

RemoteException - if remote call fails

Since:

JDK1.2

unregisterObject

public void unregisterObject(ActivationID id)
                      throws ActivationException,
                             UnknownObjectException,
                             RemoteException

Remove the activation id and associated descriptor previously registered with the ActivationSystem; the object can no longer be activated via the object's activation id.

Parameters:

id - the object's activation id (from previous registration)

Throws:

ActivationException - if unregister fails (e.g., database update failure, etc).

UnknownObjectException - if object is unknown (not registered)

RemoteException - if remote call fails

Since:

JDK1.2

registerGroup

public ActivationGroupID registerGroup(ActivationGroupDesc desc)
                                throws ActivationException,
                                       RemoteException

Register the activation group. An activation group must be registered with the ActivationSystem before objects can be registered within that group.

Parameters:

desc - the group's descriptor

Returns:

an identifier for the group

Throws:

ActivationException - if group registration fails

RemoteException - if remote call fails

Since:

JDK1.2

activeGroup

public ActivationMonitor activeGroup(ActivationGroupID id,
                                     ActivationInstantiator group,
                                     long incarnation)
                              throws UnknownGroupException,
                                     ActivationException,
                                     RemoteException

Callback to inform activation system that group is now active. This call is made internally by the ActivationGroup.createGroup method to inform the ActivationSystem that the group is now active.

Parameters:

id - the activation group's identifier

group - the group's instantiator

incarnation - the group's incarnation number

Throws:

UnknownGroupException - if group is not registered

ActivationException - if group is already active

RemoteException - if remote call fails

Since:

JDK1.2

unregisterGroup

public void unregisterGroup(ActivationGroupID id)
                     throws ActivationException,
                            UnknownGroupException,
                            RemoteException

Remove the activation group. An activation group makes this call back to inform the activator that the group should be removed (destroyed). If this call completes successfully, objects can no longer be registered or activated within the group. All information of the group and its associated objects is removed from the system.

Parameters:

id - the activation group's identifier

Throws:

ActivationException - if unregister fails (e.g., database update failure, etc).

UnknownGroupException - if group is not registered

RemoteException - if remote call fails

Since:

JDK1.2

shutdown

public void shutdown()
              throws RemoteException

Shutdown the activation system. Destroys all groups spawned by the activation daemon and exits the activation daemon.

Since:

JDK1.2

setActivationDesc

public ActivationDesc setActivationDesc(ActivationID id,
                                        ActivationDesc desc)
                                 throws ActivationException,
                                        UnknownObjectException,
                                        UnknownGroupException,
                                        RemoteException

Set the activation descriptor, desc for the object with the activation identifier, id. The change will take effect upon subsequent activation of the object.

Parameters:

id - the activation identifier for the activatable object

desc - the activation descriptor for the activatable object

Returns:

the previous value of the activation descriptor

Throws:

UnknownGroupException - the group associated with desc is not a registered group

UnknownObjectException - the activation id is not registered

ActivationException - for general failure (e.g., unable to update log)

RemoteException - if remote call fails

Since:

JDK1.2

setActivationGroupDesc

public ActivationGroupDesc setActivationGroupDesc(ActivationGroupID id,
                                                  ActivationGroupDesc desc)
                                           throws ActivationException,
                                                  UnknownGroupException,
                                                  RemoteException

Set the activation group descriptor, desc for the object with the activation group identifier, id. The change will take effect upon subsequent activation of the group.

Parameters:

id - the activation group identifier for the activation group

desc - the activation group descriptor for the activation group

Returns:

the previous value of the activation group descriptor

Throws:

UnknownGroupException - the group associated with id is not a registered group

ActivationException - for general failure (e.g., unable to update log)

RemoteException - if remote call fails

Since:

JDK1.2

getActivationDesc

public ActivationDesc getActivationDesc(ActivationID id)
                                 throws ActivationException,
                                        UnknownObjectException,
                                        RemoteException

Returns the activation descriptor, for the object with the activation identifier, id.

Parameters:

id - the activation identifier for the activatable object

Returns:

the activation descriptor

Throws:

UnknownObjectException - if id is not registered

ActivationException - for general failure

RemoteException - if remote call fails

Since:

JDK1.2

getActivationGroupDesc

public ActivationGroupDesc getActivationGroupDesc(ActivationGroupID id)
                                           throws ActivationException,
                                                  UnknownGroupException,
                                                  RemoteException

Returns the activation group descriptor, for the group with the activation group identifier, id.

Parameters:

id - the activation group identifier for the group

Returns:

the activation group descriptor

Throws:

UnknownGroupException - if id is not registered

ActivationException - for general failure

RemoteException - if remote call fails

Since:

JDK1.2