Java Platform 1.2

java.rmi.activation
Class Activatable

java.lang.Object
  |
  +--java.rmi.server.RemoteObject
        |
        +--java.rmi.server.RemoteServer
              |
              +--java.rmi.activation.Activatable
public abstract class Activatable
extends RemoteServer

The Activatable class provides support for remote objects that require persistent access over time and that can be activated by the system.

Since:
JDK1.2
See Also:
Serialized Form

Fields inherited from class java.rmi.server.RemoteObject
ref
 
Constructor Summary
protected Activatable(ActivationID id, int port)
          Constructor used to activate/export the object on a specified port.
protected Activatable(ActivationID id, int port, RMIClientSocketFactory csf, RMIServerSocketFactory ssf)
          Constructor used to activate/export the object on a specified port.
protected Activatable(String location, MarshalledObject data, boolean restart, int port)
          Constructor used to register and export the object on a specified port (an anonymous port is chosen if port=0) .
protected Activatable(String location, MarshalledObject data, boolean restart, int port, RMIClientSocketFactory csf, RMIServerSocketFactory ssf)
          Constructor used to register and export the object on a specified port (an anonymous port is chosen if port=0) .
 
Method Summary
static Remote exportObject(Remote obj, ActivationID id, int port)
          Export the activatable remote object to the RMI runtime to make the object available to receive incoming calls.
static Remote exportObject(Remote obj, ActivationID id, int port, RMIClientSocketFactory csf, RMIServerSocketFactory ssf)
          Export the activatable remote object to the RMI runtime to make the object available to receive incoming calls.
static ActivationID exportObject(Remote obj, String location, MarshalledObject data, boolean restart, int port)
          This exportObject method may be invoked explicitly by an "activatable" object, that does not extend the Activatable class, in order to both a) register the object's activation descriptor, constructed from the supplied location, and data, with the activation system (so the object can be activated), and b) export the remote object, obj, on a specific port (if port=0, then an anonymous port is chosen).
static ActivationID exportObject(Remote obj, String location, MarshalledObject data, boolean restart, int port, RMIClientSocketFactory csf, RMIServerSocketFactory ssf)
          This exportObject method may be invoked explicitly by an "activatable" object, that does not extend the Activatable class, in order to both a) register the object's activation descriptor, constructed from the supplied location, and data, with the activation system (so the object can be activated), and b) export the remote object, obj, on a specific port (if port=0, then an anonymous port is chosen).
protected  ActivationID getID()
          Returns the object's activation identifier.
static boolean inactive(ActivationID id)
          Informs the system that the object with the corresponding activation id is currently inactive.
static Remote register(ActivationDesc desc)
          Register an object descriptor for an activatable remote object so that is can be activated on demand.
static boolean unexportObject(Remote obj, boolean force)
          Remove the remote object, obj, from the RMI runtime.
static void unregister(ActivationID id)
          Revokes previous registration for the activation descriptor associated with id.
 
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
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
 

Constructor Detail

Activatable

protected Activatable(String location,
                      MarshalledObject data,
                      boolean restart,
                      int port)
               throws ActivationException,
                      RemoteException
Constructor used to register and export the object on a specified port (an anonymous port is chosen if port=0) . A concrete subclass of this class must call this constructor to register and export the object during initial construction. As a side-effect of activatable object construction, the remote object is both "registered" with the activation system and "exported" (on an anonymous port if port=0) to the RMI runtime so that it is available to accept incoming calls from clients.
Parameters:
location - the location for classes for this object
data - the object's initialization data
port - the port on which the object is exported (an anonymous port is used if port=0)
restart - if true, the object is restarted when the activator is restarted; if false, the object is activated on demand.
Throws:
ActivationException - if object registration fails.
RemoteException - if either of the following fails: a) registering the object with the activation system or b) exporting the object to the RMI runtime.
Since:
JDK1.2

Activatable

protected Activatable(String location,
                      MarshalledObject data,
                      boolean restart,
                      int port,
                      RMIClientSocketFactory csf,
                      RMIServerSocketFactory ssf)
               throws ActivationException,
                      RemoteException
Constructor used to register and export the object on a specified port (an anonymous port is chosen if port=0) .

A concrete subclass of this class must call this constructor to register and export the object during initial construction. As a side-effect of activatable object construction, the remote object is both "registered" with the activation system and "exported" (on an anonymous port if port=0) to the RMI runtime so that it is available to accept incoming calls from clients. Note that objects created via this constructor will be activated on demand, not restarted when the activation daemon starts. If an activatable objects requires restart when the activation daemon rmid starts, use the second Activatable constructor form.

Parameters:
location - the location for classes for this object
data - the object's initialization data
restart - if true, the object is restarted when the activator is restarted; if false, the object is activated on demand.
port - the port on which the object is exported (an anonymous port is used if port=0)
csf - the client-side socket factory for making calls to the remote object
ssf - the server-side socket factory for receiving remote calls
Throws:
ActivationException - if object registration fails.
RemoteException - if either of the following fails: a) registering the object with the activation system or b) exporting the object to the RMI runtime.
Since:
JDK1.2

Activatable

protected Activatable(ActivationID id,
                      int port)
               throws RemoteException
Constructor used to activate/export the object on a specified port. An "activatable" remote object must have a constructor that takes two arguments:

A concrete subclass of this class must call this constructor when it is activated via the two parameter constructor described above. As a side-effect of construction, the remote object is "exported" to the RMI runtime (on the specified port) and is available to accept incoming calls from clients.

Parameters:
id - activation identifier for the object
port - the port number on which the object is exported
Throws:
RemoteException - if exporting the object to the RMI runtime fails
Since:
JDK1.2

Activatable

protected Activatable(ActivationID id,
                      int port,
                      RMIClientSocketFactory csf,
                      RMIServerSocketFactory ssf)
               throws RemoteException
Constructor used to activate/export the object on a specified port. An "activatable" remote object must have a constructor that takes two arguments:

A concrete subclass of this class must call this constructor when it is activated via the two parameter constructor described above. As a side-effect of construction, the remote object is "exported" to the RMI runtime (on the specified port) and is available to accept incoming calls from clients.

Parameters:
id - activation identifier for the object
port - the port number on which the object is exported
csf - the client-side socket factory for making calls to the remote object
ssf - the server-side socket factory for receiving remote calls
Throws:
RemoteException - if exporting the object to the RMI runtime fails
Since:
JDK1.2
Method Detail

getID

protected ActivationID getID()
Returns the object's activation identifier. The method is protected so that only subclasses can obtain an object's identifier.
Returns:
the object's activation identifier
Since:
JDK1.2

register

public static Remote register(ActivationDesc desc)
                       throws UnknownGroupException,
                              ActivationException,
                              RemoteException
Register an object descriptor for an activatable remote object so that is can be activated on demand.
Parameters:
desc - the object's descriptor
Returns:
the stub for the activatable remote object
Throws:
UnknownGroupException - if group id in desc is not registered with the activation system
ActivationException - if activation system is not running
RemoteException - if remote call fails
Since:
JDK1.2

inactive

public static boolean inactive(ActivationID id)
                        throws UnknownObjectException,
                               ActivationException,
                               RemoteException
Informs the system that the object with the corresponding activation id is currently inactive. If the object is currently active, the object is "unexported" from the RMI runtime (only if there are no pending or in-progress calls) so the that it can no longer receive incoming calls. This call informs this VM's ActivationGroup that the object is inactive, that, in turn, informs its ActivationMonitor. If this call completes successfully, a subsequent activate request to the activator will cause the object to reactivate. The operation may still succeed if the object is considered active but has already unexported itself.
Parameters:
id - the object's activation identifier
Throws:
UnknownObjectException - if object is not known (it may already be inactive)
ActivationException - if group is not active
RemoteException - if call informing monitor fails
Since:
JDK1.2

unregister

public static void unregister(ActivationID id)
                       throws UnknownObjectException,
                              ActivationException,
                              RemoteException
Revokes previous registration for the activation descriptor associated with id. An object can no longer be activated via that id.
Parameters:
id - the object's activation identifier
Throws:
UnknownObjectException - if object (id) is unknown
ActivationException - if activation system is not running
RemoteException - if remote call to activation system fails
Since:
JDK1.2

exportObject

public static ActivationID exportObject(Remote obj,
                                        String location,
                                        MarshalledObject data,
                                        boolean restart,
                                        int port)
                                 throws ActivationException,
                                        RemoteException
This exportObject method may be invoked explicitly by an "activatable" object, that does not extend the Activatable class, in order to both a) register the object's activation descriptor, constructed from the supplied location, and data, with the activation system (so the object can be activated), and b) export the remote object, obj, on a specific port (if port=0, then an anonymous port is chosen). Once the object is exported, it can receive incoming RMI calls.

This method does not need to be called if obj extends Activatable, since the first constructor calls this method.

Parameters:
obj - the object being exported
location - the object's code location
data - the object's bootstrapping data
restart - if true, the object is restarted when the activator is restarted; if false, the object is activated on demand.
port - the port on which the object is exported (an anonymous port is used if port=0)
Throws:
ActivationException - if activation group is not active
RemoteException - if object registration or export fails
Since:
JDK1.2

exportObject

public static ActivationID exportObject(Remote obj,
                                        String location,
                                        MarshalledObject data,
                                        boolean restart,
                                        int port,
                                        RMIClientSocketFactory csf,
                                        RMIServerSocketFactory ssf)
                                 throws ActivationException,
                                        RemoteException
This exportObject method may be invoked explicitly by an "activatable" object, that does not extend the Activatable class, in order to both a) register the object's activation descriptor, constructed from the supplied location, and data, with the activation system (so the object can be activated), and b) export the remote object, obj, on a specific port (if port=0, then an anonymous port is chosen). Once the object is exported, it can receive incoming RMI calls.

This method does not need to be called if obj extends Activatable, since the first constructor calls this method.

Parameters:
obj - the object being exported
location - the object's code location
data - the object's bootstrapping data
restart - if true, the object is restarted when the activator is restarted; if false, the object is activated on demand.
port - the port on which the object is exported (an anonymous port is used if port=0)
csf - the client-side socket factory for making calls to the remote object
ssf - the server-side socket factory for receiving remote calls
Returns:
the activation identifier obtained from registering the descriptor, desc, with the activation system the wrong group
Throws:
ActivationException - if activation group is not active
RemoteException - if object registration or export fails
Since:
JDK1.2

exportObject

public static Remote exportObject(Remote obj,
                                  ActivationID id,
                                  int port)
                           throws RemoteException
Export the activatable remote object to the RMI runtime to make the object available to receive incoming calls. The object is exported on an anonymous port, if port is zero.

During activation, this exportObject method should be invoked explicitly by an "activatable" object, that does not extend the Activatable class. There is no need for objects that do extend the Activatable class to invoke this method directly; this method is called by the second constructor above (which a subclass should invoke from its special activation constructor).

Parameters:
obj - the remote object implementation
id - the object's activation identifier
port - the port on which the object is exported (an anonymous port is used if port=0)
Returns:
the stub for the activatable remote object
Throws:
RemoteException - if object export fails
Since:
JDK1.2

exportObject

public static Remote exportObject(Remote obj,
                                  ActivationID id,
                                  int port,
                                  RMIClientSocketFactory csf,
                                  RMIServerSocketFactory ssf)
                           throws RemoteException
Export the activatable remote object to the RMI runtime to make the object available to receive incoming calls. The object is exported on an anonymous port, if port is zero.

During activation, this exportObject method should be invoked explicitly by an "activatable" object, that does not extend the Activatable class. There is no need for objects that do extend the Activatable class to invoke this method directly; this method is called by the second constructor above (which a subclass should invoke from its special activation constructor).

Parameters:
obj - the remote object implementation
id - the object's activation identifier
port - the port on which the object is exported (an anonymous port is used if port=0)
csf - the client-side socket factory for making calls to the remote object
ssf - the server-side socket factory for receiving remote calls
Returns:
the stub for the activatable remote object
Throws:
RemoteException - if object export fails
Since:
JDK1.2

unexportObject

public static boolean unexportObject(Remote obj,
                                     boolean force)
                              throws NoSuchObjectException
Remove the remote object, obj, from the RMI runtime. If successful, the object can no longer accept incoming RMI calls. If the force parameter is true, the object is forcibly unexported even if there are pending calls to the remote object or the remote object still has calls in progress. If the force parameter is false, the object is only unexported if there are no pending or in progress calls to the object.
Parameters:
obj - the remote object to be unexported
force - if true, unexports the object even if there are pending or in-progress calls; if false, only unexports the object if there are no pending or in-progress calls
Returns:
true if operation is successful, false otherwise
Throws:
NoSuchObjectException - if the remote object is not currently exported
Since:
JDK1.2
Java Platform 1.2
Submit a bug or feature Version 1.2 of Java Platform API Specification
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