/**********************************************************************************
* $URL: https://source.sakaiproject.org/svn/kernel/trunk/api/src/main/java/org/sakaiproject/event/api/ActivityService.java $
* $Id: ActivityService.java 121849 2013-03-27 19:00:36Z azeckoski@unicon.net $
***********************************************************************************
*
* Copyright (c) 2003, 2004, 2005, 2006, 2008 Sakai Foundation
*
* Licensed under the Educational Community License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.opensource.org/licenses/ECL-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
**********************************************************************************/
package org.sakaiproject.event.api;
import java.util.List;
import java.util.Map;
/**
*
* ActivityService provides the ability to check if users are online and when they were last active.
*
* <p>
* Users are registered and updated each time they publish an event. As such you can tell <b>if</b> a user is active
* and <b>when</b> they were last active (last event time).
* </p>
*
* <p>
* For clustered environments, you may experience discrepancies when a new node comes online as the cache will start afresh
* so users will only be repopulated into the cache once they start publishing events.</p>
*
* @since 1.2.1
*/
public interface ActivityService {
/**
* Check if a userId has an active Sakai session.
* @param userId userId to check
* @return true if active, false if not
*/
public boolean isUserActive(String userId);
/**
* Get the list of users with active Sakai sessions, given the supplied list of userIds.
* @param userIds userIds to check
* @return List of userIds that have active Sakai sessions
*/
public List<String> getActiveUsers(List<String> userIds);
/**
* Get last event time for the given user
*
* @param userId userId to check
* @return time of event as Long, null if no event.
*/
Long getLastEventTimeForUser(String userId);
/**
* Get last event time for the given list of users
*
* @param userIds List of userId's to check
* @return map of userId and time of last event. If no event, there will be no entry in the map for that user.
*/
Map<String, Long> getLastEventTimeForUsers(List<String> userIds);
}