001    /*
002     * Licensed to the Apache Software Foundation (ASF) under one
003     * or more contributor license agreements.  See the NOTICE file
004     * distributed with this work for additional information
005     * regarding copyright ownership.  The ASF licenses this file
006     * to you under the Apache License, Version 2.0 (the
007     * "License"); you may not use this file except in compliance
008     * with the License.  You may obtain a copy of the License at
009     *
010     *     http://www.apache.org/licenses/LICENSE-2.0
011     *
012     * Unless required by applicable law or agreed to in writing,
013     * software distributed under the License is distributed on an
014     * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015     * KIND, either express or implied.  See the License for the
016     * specific language governing permissions and limitations
017     * under the License.
018     */
019    package org.apache.shiro.session.mgt.eis;
020    
021    import org.apache.shiro.cache.AbstractCacheManager;
022    import org.apache.shiro.cache.Cache;
023    import org.apache.shiro.cache.CacheException;
024    import org.apache.shiro.cache.MapCache;
025    import org.apache.shiro.session.Session;
026    
027    import java.io.Serializable;
028    import java.util.concurrent.ConcurrentHashMap;
029    
030    /**
031     * SessionDAO implementation that relies on an enterprise caching product as the EIS system of record for all sessions.
032     * It is expected that an injected {@link org.apache.shiro.cache.Cache Cache} or
033     * {@link org.apache.shiro.cache.CacheManager CacheManager} is backed by an enterprise caching product that can support
034     * all application sessions and/or provide disk paging for resilient data storage.
035     * <h2>Production Note</h2>
036     * This implementation defaults to using an in-memory map-based {@code CacheManager}, which is great for testing but
037     * will typically not scale for production environments and could easily cause {@code OutOfMemoryException}s.  Just
038     * don't forget to configure<b>*</b> an instance of this class with a production-grade {@code CacheManager} that can
039     * handle disk paging for large numbers of sessions and you'll be fine.
040     * <p/>
041     * <b>*</b>If you configure Shiro's {@code SecurityManager} instance with such a {@code CacheManager}, it will be
042     * automatically applied to an instance of this class and you won't need to explicitly set it in configuration.
043     * <h3>Implementation Details</h3>
044     * This implementation relies heavily on the {@link CachingSessionDAO parent class}'s transparent caching behavior for
045     * all storage operations with the enterprise caching product.  Because the parent class uses a {@code Cache} or
046     * {@code CacheManager} to perform caching, and the cache is considered the system of record, nothing further needs to
047     * be done for the {@link #doReadSession}, {@link #doUpdate} and {@link #doDelete} method implementations.  This class
048     * implements those methods as required by the parent class, but they essentially do nothing.
049     *
050     * @since 1.0
051     */
052    public class EnterpriseCacheSessionDAO extends CachingSessionDAO {
053    
054        public EnterpriseCacheSessionDAO() {
055            setCacheManager(new AbstractCacheManager() {
056                @Override
057                protected Cache<Serializable, Session> createCache(String name) throws CacheException {
058                    return new MapCache<Serializable, Session>(name, new ConcurrentHashMap<Serializable, Session>());
059                }
060            });
061        }
062    
063        protected Serializable doCreate(Session session) {
064            Serializable sessionId = generateSessionId(session);
065            assignSessionId(session, sessionId);
066            return sessionId;
067        }
068    
069        protected Session doReadSession(Serializable sessionId) {
070            return null; //should never execute because this implementation relies on parent class to access cache, which
071            //is where all sessions reside - it is the cache implementation that determines if the
072            //cache is memory only or disk-persistent, etc.
073        }
074    
075        protected void doUpdate(Session session) {
076            //does nothing - parent class persists to cache.
077        }
078    
079        protected void doDelete(Session session) {
080            //does nothing - parent class removes from cache.
081        }
082    }