/*
* JBoss, Home of Professional Open Source.
* Copyright 2008, Red Hat Middleware LLC, and individual contributors
* as indicated by the @author tags. See the copyright.txt file in the
* distribution for a full listing of individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.jboss.ha.hasessionstate.interfaces;
import org.jboss.ha.hasessionstate.interfaces.PackagedSession;
import org.jboss.ha.framework.interfaces.HAPartition;
/**
* Interface for services providing clustered state session availability
*
* @see org.jboss.ha.hasessionstate.server.HASessionStateImpl
*
* @author <a href="mailto:sacha.labourey@cogito-info.ch">Sacha Labourey</a>
* @version $Revision: 81001 $
*
* <p><b>Revisions:</b><br>
*/
public interface HASessionState
{
public void init () throws Exception;
public void start () throws Exception;
/**
* Listener used to indicate that a session's state has changed.
* Information that can be used to clean a cache for example. It indicates that
* another node has touched a session that we previously owned.
*
*/
public interface HASessionStateListener
{
public void sessionExternallyModified (PackagedSession session);
}
/**
* Subscribe to receive notifications when objects gets modified on another node.
*
*/
public void subscribe (String appName, HASessionStateListener listener);
public void unsubscribe (String appName, HASessionStateListener listener);
public HAPartition getCurrentHAPartition ();
/**
* Return the name of this node as used in the computations
*/
public String getNodeName ();
/**
* Share a new session state in the sub-partition of this cluster
* @param appName Application name for which is state is shared
* @param keyId Key identifier of the state
*/
public void createSession (String appName, Object keyId);
/**
* Modifies a state already shared
* @param appName Application name hosting this state
* @param keyId Key identifier of the state to modify
* @param state New state
*/
public void setState (String appName, Object keyId, byte[] state)
throws java.rmi.RemoteException;
/**
* Get a particular state
* @param appName Application hosting the state
* @param keyId Key identifier of the state
* @return The state value
*/
public PackagedSession getState (String appName, Object keyId);
/**
* Get a state and, if it is not already the case, takes its ownership (a state is
* always owned by a node)
* @param appName Application hosting the state
* @param keyId Key identifier of the state
* @throws java.rmi.RemoteException Thrown if an exception occurs while getting the ownership of the state
* @return The state value
*/
public PackagedSession getStateWithOwnership (String appName, Object keyId) throws java.rmi.RemoteException;
/**
* Take ownership of a state. Each state is owned by a node.
* @param appName Application hosting the state
* @param keyId Key identifier of the state
* @throws java.rmi.RemoteException Trown if a communication exception occurs while asking other node to get the ownership
*/
public void takeOwnership (String appName, Object keyId) throws java.rmi.RemoteException;
/**
* Remove a session from the sub-partition
* @param appName Application hosting the state
* @param keyId Key identifier of the state
*/
public void removeSession (String appName, Object keyId);
}