/**********************************************************************************
* $URL: https://source.sakaiproject.org/svn/presence/trunk/presence-api/api/src/java/org/sakaiproject/presence/api/PresenceService.java $
* $Id: PresenceService.java 105079 2012-02-24 23:08:11Z ottenhoff@longsight.com $
***********************************************************************************
*
* Copyright (c) 2003, 2004, 2005, 2006, 2007, 2008 The 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.presence.api;
import java.util.List;
import org.sakaiproject.event.api.UsageSession;
import org.sakaiproject.user.api.User;
/**
* <p>
* A PresenceService keeps track of a session's presence at various locations in the system.
* </p>
* <p>
* Location is a combination of site id, (optional) page id and (optional) tool id
* </p>
*/
public interface PresenceService
{
/** This string starts the references to resources in this service. */
static final String REFERENCE_ROOT = "/presence";
/** Name for the event of establishing presence at a location. */
static final String EVENT_PRESENCE = "pres.begin";
/** Name for the event of ending presence at a location. */
static final String EVENT_ABSENCE = "pres.end";
/**
* Form a presence reference from a location id
*
* @param id
* the location id.
* @return A presence reference based on a location id.
*/
String presenceReference(String id);
/**
* Construct a location id from site, page, and tool.
*
* @param site
* The site id.
* @param page
* The page id (optional).
* @param tool
* The tool id (optional).
* @return a Location Id.
*/
String locationId(String site, String page, String tool);
/**
* Form a description for the location.
*
* @param location
* The presence location.
* @return A description for the location.
*/
String getLocationDescription(String location);
/**
* Establish or refresh the presence of the current session in a location.
*
* @param session
* The session object.
* @param locationId
* A presence location id.
*/
void setPresence(String locationId);
/**
* Establish or refresh the presence of the current session in a location.
*
* @param session
* The session object.
* @param locationId
* A presence location id.
* @param timeout
* The length of time in seconds for which the presence should persist before timing out if not refreshed.
*/
void setPresence(String locationId, int timeout);
/**
* Remove the presence of the current session from a location.
*
* @param session
* The session object.
* @param locationId
* A presence location id.
*/
void removePresence(String locationId);
/**
* Remove presence in all locations for the given session.
*
* @param session
* The session object.
* @param sessionId
* A session id.
*/
void removeSessionPresence(String sessionId);
/**
* Access a List of sessions (UsageSession) now present in a location.
*
* @param locationId
* A presence location id.
* @return The a List of sessions (UsageSession) now present in the location (may be empty).
*/
List<UsageSession> getPresence(String locationId);
/**
* Access a List of users (User) now present in a location.
*
* @param locationId
* A presence location id.
* @return The a List of users (User) now present in the location (may be empty).
*/
List<User> getPresentUsers(String locationId);
/**
* Access a List of users (User) now present in a location.
*
* @param locationId
* A presence location id.
* @param siteId
* A siteId (added when integrating PrivacyManager)
*
* @return The a List of users (User) now present in the location (may be empty).
*/
List<User> getPresentUsers(String locationId, String siteId);
/**
* Access a List of all location ids (String).
*
* @return The List of all location ids (Strings) (may be empty).
*/
List<String> getLocations();
/**
* Access the time (in seconds) after which a presence will timeout.
*
* @return The time (seconds) after which a presence will timeout.
*/
int getTimeout();
}