java.rmi.activation

Class ActivationID

java.lang.Object

java.rmi.activation.ActivationID

All Implemented Interfaces:

Serializable

public class ActivationID
extends Object
implements Serializable

Activation makes use of special identifiers to denote remote objects that can be activated over time. An activation identifier (an instance of the class ActivationID) contains several pieces of information needed for activating an object:

• a remote reference to the object's activator (a RemoteRef instance), and
• a unique identifier (a UID instance) for the object.

An activation identifier for an object can be obtained by registering an object with the activation system. Registration is accomplished in a few ways:

• via the Activatable.register method
• via the first Activatable constructor (that takes three arguments and both registers and exports the object, and
• via the first Activatable.exportObject method that takes the activation descriptor, object and port as arguments; this method both registers and exports the object.

Since:

1.2

See Also:

Activatable, Serialized Form

Constructor Summary

Constructors

Constructor and Description
ActivationID(Activator activator) The constructor for ActivationID takes a single argument, activator, that specifies a remote reference to the activator responsible for activating the object associated with this identifier.

Method Summary

Modifier and Type	Method and Description
Remote	activate(boolean force) Activate the object for this id.
boolean	equals(Object obj) Compares two activation ids for content equality.
int	hashCode() Returns a hashcode for the activation id.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ActivationID

public ActivationID(Activator activator)

The constructor for ActivationID takes a single argument, activator, that specifies a remote reference to the activator responsible for activating the object associated with this identifier. An instance of ActivationID is globally unique.

Parameters:

activator - reference to the activator responsible for activating the object

Throws:

UnsupportedOperationException - if and only if activation is not supported by this implementation

Since:

1.2

Method Detail

activate

public Remote activate(boolean force)
                throws ActivationException,
                       UnknownObjectException,
                       RemoteException

Activate the object for this id.

Parameters:

force - if true, forces the activator to contact the group when activating the object (instead of returning a cached reference); if false, returning a cached value is acceptable.

Returns:

the reference to the active remote object

Throws:

ActivationException - if activation fails

UnknownObjectException - if the object is unknown

RemoteException - if remote call fails

Since:

1.2

hashCode

public int hashCode()

Returns a hashcode for the activation id. Two identifiers that refer to the same remote object will have the same hash code.

Overrides:

hashCode in class Object

Returns:

a hash code value for this object.

Since:

1.2

See Also:

Hashtable

equals

public boolean equals(Object obj)

Compares two activation ids for content equality. Returns true if both of the following conditions are true: 1) the unique identifiers equivalent (by content), and 2) the activator specified in each identifier refers to the same remote object.

Overrides:

equals in class Object

Parameters:

obj - the Object to compare with

Returns:

true if these Objects are equal; false otherwise.

Since:

1.2

See Also:

Hashtable