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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

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 * particular file as subject to the "Classpath" exception as provided

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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

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package java.rmi.activation;

import java.rmi.Remote;

import java.rmi.RemoteException;

import java.rmi.activation.UnknownGroupException;

import java.rmi.activation.UnknownObjectException;

/**

 * The <code>ActivationSystem</code> provides a means for registering

 * groups and "activatable" objects to be activated within those groups.

 * The <code>ActivationSystem</code> works closely with the

 * <code>Activator</code>, which activates objects registered via the

 * <code>ActivationSystem</code>, and the <code>ActivationMonitor</code>,

 * which obtains information about active and inactive objects,

 * and inactive groups.

 *

 * @author      Ann Wollrath

 * @see         Activator

 * @see         ActivationMonitor

 * @since       1.2

 */

public interface ActivationSystem extends Remote {

    /** The port to lookup the activation system. */

    public static final int SYSTEM_PORT = 1098;

    /**

     * The <code>registerObject</code> method is used to register an

     * activation descriptor, <code>desc</code>, and obtain an

     * activation identifier for a activatable remote object. The

     * <code>ActivationSystem</code> creates an

     * <code>ActivationID</code> (a activation identifier) for the

     * object specified by the descriptor, <code>desc</code>, and

     * records, in stable storage, the activation descriptor and its

     * associated identifier for later use. When the <code>Activator</code>

     * receives an <code>activate</code> 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.

     *

     * @param desc the object's activation descriptor

     * @return the activation id that can be used to activate the object

     * @exception ActivationException if registration fails (e.g., database

     * update failure, etc).

     * @exception UnknownGroupException if group referred to in

     * <code>desc</code> is not registered with this system

     * @exception RemoteException if remote call fails

     * @since 1.2

     */

    public ActivationID registerObject(ActivationDesc desc)

        throws ActivationException, UnknownGroupException, RemoteException;

    /**

     * Remove the activation id and associated descriptor previously

     * registered with the <code>ActivationSystem</code>; the object

     * can no longer be activated via the object's activation id.

     *

     * @param id the object's activation id (from previous registration)

     * @exception ActivationException if unregister fails (e.g., database

     * update failure, etc).

     * @exception UnknownObjectException if object is unknown (not registered)

     * @exception RemoteException if remote call fails

     * @since 1.2

     */

    public void unregisterObject(ActivationID id)

        throws ActivationException, UnknownObjectException, RemoteException;

    /**

     * Register the activation group. An activation group must be

     * registered with the <code>ActivationSystem</code> before objects

     * can be registered within that group.

     *

     * @param desc the group's descriptor

     * @return an identifier for the group

     * @exception ActivationException if group registration fails

     * @exception RemoteException if remote call fails

     * @since 1.2

     */

    public ActivationGroupID registerGroup(ActivationGroupDesc desc)

        throws ActivationException, RemoteException;

    /**

     * Callback to inform activation system that group is now

     * active. This call is made internally by the

     * <code>ActivationGroup.createGroup</code> method to inform

     * the <code>ActivationSystem</code> that the group is now

     * active.

     *

     * @param id the activation group's identifier

     * @param group the group's instantiator

     * @param incarnation the group's incarnation number

     * @return monitor for activation group

     * @exception UnknownGroupException if group is not registered

     * @exception ActivationException if a group for the specified

     * <code>id</code> is already active and that group is not equal

     * to the specified <code>group</code> or that group has a different

     * <code>incarnation</code> than the specified <code>group</code>

     * @exception RemoteException if remote call fails

     * @since 1.2

     */

    public ActivationMonitor activeGroup(ActivationGroupID id,

                                         ActivationInstantiator group,

                                         long incarnation)

        throws UnknownGroupException, ActivationException, 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.

     *

     * @param id the activation group's identifier

     * @exception ActivationException if unregister fails (e.g., database

     * update failure, etc).

     * @exception UnknownGroupException if group is not registered

     * @exception RemoteException if remote call fails

     * @since 1.2

     */

    public void unregisterGroup(ActivationGroupID id)

        throws ActivationException, UnknownGroupException, RemoteException;

    /**

     * Shutdown the activation system. Destroys all groups spawned by

     * the activation daemon and exits the activation daemon.

     * @exception RemoteException if failed to contact/shutdown the activation

     * daemon

     * @since 1.2

     */

    public void shutdown() throws RemoteException;

    /**

     * Set the activation descriptor, <code>desc</code> for the object with

     * the activation identifier, <code>id</code>. The change will take

     * effect upon subsequent activation of the object.

     *

     * @param id the activation identifier for the activatable object

     * @param desc the activation descriptor for the activatable object

     * @exception UnknownGroupException the group associated with

     * <code>desc</code> is not a registered group

     * @exception UnknownObjectException the activation <code>id</code>

     * is not registered

     * @exception ActivationException for general failure (e.g., unable

     * to update log)

     * @exception RemoteException if remote call fails

     * @return the previous value of the activation descriptor

     * @see #getActivationDesc

     * @since 1.2

     */

    public ActivationDesc setActivationDesc(ActivationID id,

                                            ActivationDesc desc)

        throws ActivationException, UnknownObjectException,

            UnknownGroupException, RemoteException;

    /**

     * Set the activation group descriptor, <code>desc</code> for the object

     * with the activation group identifier, <code>id</code>. The change will

     * take effect upon subsequent activation of the group.

     *

     * @param id the activation group identifier for the activation group

     * @param desc the activation group descriptor for the activation group

     * @exception UnknownGroupException the group associated with

     * <code>id</code> is not a registered group

     * @exception ActivationException for general failure (e.g., unable

     * to update log)

     * @exception RemoteException if remote call fails

     * @return the previous value of the activation group descriptor

     * @see #getActivationGroupDesc

     * @since 1.2

     */

    public ActivationGroupDesc setActivationGroupDesc(ActivationGroupID id,

                                                      ActivationGroupDesc desc)

       throws ActivationException, UnknownGroupException, RemoteException;

    /**

     * Returns the activation descriptor, for the object with the activation

     * identifier, <code>id</code>.

     *

     * @param id the activation identifier for the activatable object

     * @exception UnknownObjectException if <code>id</code> is not registered

     * @exception ActivationException for general failure

     * @exception RemoteException if remote call fails

     * @return the activation descriptor

     * @see #setActivationDesc

     * @since 1.2

     */

    public ActivationDesc getActivationDesc(ActivationID id)

       throws ActivationException, UnknownObjectException, RemoteException;

    /**

     * Returns the activation group descriptor, for the group

     * with the activation group identifier, <code>id</code>.

     *

     * @param id the activation group identifier for the group

     * @exception UnknownGroupException if <code>id</code> is not registered

     * @exception ActivationException for general failure

     * @exception RemoteException if remote call fails

     * @return the activation group descriptor

     * @see #setActivationGroupDesc

     * @since 1.2

     */

    public ActivationGroupDesc getActivationGroupDesc(ActivationGroupID id)

       throws ActivationException, UnknownGroupException, RemoteException;

}