001package org.apache.turbine.services.session;
002
003
004/*
005 * Licensed to the Apache Software Foundation (ASF) under one
006 * or more contributor license agreements.  See the NOTICE file
007 * distributed with this work for additional information
008 * regarding copyright ownership.  The ASF licenses this file
009 * to you under the Apache License, Version 2.0 (the
010 * "License"); you may not use this file except in compliance
011 * with the License.  You may obtain a copy of the License at
012 *
013 *   http://www.apache.org/licenses/LICENSE-2.0
014 *
015 * Unless required by applicable law or agreed to in writing,
016 * software distributed under the License is distributed on an
017 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
018 * KIND, either express or implied.  See the License for the
019 * specific language governing permissions and limitations
020 * under the License.
021 */
022
023
024import java.util.Collection;
025
026import javax.servlet.http.HttpSession;
027
028import org.apache.turbine.om.security.User;
029import org.apache.turbine.services.Service;
030
031/**
032 * The SessionService allows access to the current sessions of the current context.
033 * The session objects that are cached by this service are obtained through
034 * a listener.  The listener must be configured in your web.xml file.
035 *
036 * @author <a href="mailto:quintonm@bellsouth.net">Quinton McCombs</a>
037 * @since 2.3
038 * @see org.apache.turbine.services.session.SessionListener
039 * @version $Id$
040 */
041public interface SessionService extends Service
042{
043
044    /**
045     * The key under which this service is stored in TurbineServices.
046     */
047    String SERVICE_NAME = "SessionService";
048
049    /**
050     * Gets all active sessions
051     *
052     * @return Collection of HttpSession objects
053     */
054    Collection<HttpSession> getActiveSessions();
055
056    /**
057     * Adds a session to the current list.  This method should only be
058     * called by the listener.
059     *
060     * @param session Session to add
061     */
062    void addSession(HttpSession session);
063
064    /**
065     * Removes a session from the current list.  This method should only be
066     * called by the listener.
067     *
068     * @param session Session to remove
069     */
070    void removeSession(HttpSession session);
071
072    /**
073     * Determines if a given user is currently logged in.  The actual
074     * implementation of the User object must implement the equals()
075     * method.  By default, Torque based objects (liek TurbineUser)
076     * have an implementation of equals() that will compare the
077     * result of getPrimaryKey().
078     *
079     * @param user User to check for
080     * @return true if the user is logged in on one of the
081     * active sessions.
082     */
083    boolean isUserLoggedIn(User user);
084
085    /**
086     * Gets a collection of all user objects representing the users currently
087     * logged in.  This will exclude any instances of anonymous user that
088     * Turbine will use before the user actually logs on.
089     *
090     * @return collection of org.apache.turbine.om.security.User objects
091     */
092    Collection<User> getActiveUsers();
093
094    /**
095     * Gets the User object of the the specified HttpSession.
096     *
097     * @param session The session from which to extract a user.
098     * @return The Turbine User object.
099     */
100    User getUserFromSession(HttpSession session);
101
102    /**
103     * Gets the HttpSession by the session identifier
104     *
105     * @param sessionId The unique session identifier.
106     * @return The session keyed by the specified identifier.
107     */
108    HttpSession getSession(String sessionId);
109
110    /**
111     * Get a collection of all session on which the given user
112     * is logged in.
113     *
114     * @param user the user
115     * @return Collection of HtttSession objects
116     */
117    Collection<HttpSession> getSessionsForUser(User user);
118}