| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache 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.apache.org/licenses/LICENSE-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.apache.shiro.session.mgt.eis; |
| |
| import org.apache.shiro.session.Session; |
| import org.apache.shiro.session.UnknownSessionException; |
| import org.apache.shiro.util.CollectionUtils; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| import java.io.Serializable; |
| import java.util.Collection; |
| import java.util.Collections; |
| import java.util.concurrent.ConcurrentHashMap; |
| import java.util.concurrent.ConcurrentMap; |
| |
| |
| /** |
| * Simple memory-based implementation of the SessionDAO that stores all of its sessions in an in-memory |
| * {@link ConcurrentMap}. <b>This implementation does not page to disk and is therefore unsuitable for applications |
| * that could experience a large amount of sessions</b> and would therefore cause {@code OutOfMemoryException}s. It is |
| * <em>not</em> recommended for production use in most environments. |
| * <h2>Memory Restrictions</h2> |
| * If your application is expected to host many sessions beyond what can be stored in the |
| * memory available to the JVM, it is highly recommended to use a different {@code SessionDAO} implementation which |
| * uses a more expansive or permanent backing data store. |
| * <p/> |
| * In this case, it is recommended to instead use a custom |
| * {@link CachingSessionDAO} implementation that communicates with a higher-capacity data store of your choice |
| * (file system, database, etc.). |
| * <h2>Changes in 1.0</h2> |
| * This implementation prior to 1.0 used to subclass the {@link CachingSessionDAO}, but this caused problems with many |
| * cache implementations that would expunge entries due to TTL settings, resulting in Sessions that would be randomly |
| * (and permanently) lost. The Shiro 1.0 release refactored this implementation to be 100% memory-based (without |
| * {@code Cache} usage to avoid this problem. |
| * |
| * @see CachingSessionDAO |
| * @since 0.1 |
| */ |
| public class MemorySessionDAO extends AbstractSessionDAO { |
| |
| private static final Logger log = LoggerFactory.getLogger(MemorySessionDAO.class); |
| |
| private ConcurrentMap<Serializable, Session> sessions; |
| |
| public MemorySessionDAO() { |
| this.sessions = new ConcurrentHashMap<Serializable, Session>(); |
| } |
| |
| protected Serializable doCreate(Session session) { |
| Serializable sessionId = generateSessionId(session); |
| assignSessionId(session, sessionId); |
| storeSession(sessionId, session); |
| return sessionId; |
| } |
| |
| protected Session storeSession(Serializable id, Session session) { |
| if (id == null) { |
| throw new NullPointerException("id argument cannot be null."); |
| } |
| return sessions.putIfAbsent(id, session); |
| } |
| |
| protected Session doReadSession(Serializable sessionId) { |
| return sessions.get(sessionId); |
| } |
| |
| public void update(Session session) throws UnknownSessionException { |
| storeSession(session.getId(), session); |
| } |
| |
| public void delete(Session session) { |
| if (session == null) { |
| throw new NullPointerException("session argument cannot be null."); |
| } |
| Serializable id = session.getId(); |
| if (id != null) { |
| sessions.remove(id); |
| } |
| } |
| |
| public Collection<Session> getActiveSessions() { |
| Collection<Session> values = sessions.values(); |
| if (CollectionUtils.isEmpty(values)) { |
| return Collections.emptySet(); |
| } else { |
| return Collections.unmodifiableCollection(values); |
| } |
| } |
| |
| } |