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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one
3    * or more contributor license agreements.  See the NOTICE file
4    * distributed with this work for additional information
5    * regarding copyright ownership.  The ASF licenses this file
6    * to you under the Apache License, Version 2.0 (the
7    * "License"); you may not use this file except in compliance
8    * with the License.  You may obtain a copy of the License at
9    *
10   *     http://www.apache.org/licenses/LICENSE-2.0
11   *
12   * Unless required by applicable law or agreed to in writing,
13   * software distributed under the License is distributed on an
14   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15   * KIND, either express or implied.  See the License for the
16   * specific language governing permissions and limitations
17   * under the License.
18   */
19  package org.apache.shiro.session.mgt.eis;
20  
21  import org.apache.shiro.cache.AbstractCacheManager;
22  import org.apache.shiro.cache.Cache;
23  import org.apache.shiro.cache.CacheException;
24  import org.apache.shiro.cache.MapCache;
25  import org.apache.shiro.session.Session;
26  
27  import java.io.Serializable;
28  import java.util.concurrent.ConcurrentHashMap;
29  
30  /**
31   * SessionDAO implementation that relies on an enterprise caching product as the EIS system of record for all sessions.
32   * It is expected that an injected {@link org.apache.shiro.cache.Cache Cache} or
33   * {@link org.apache.shiro.cache.CacheManager CacheManager} is backed by an enterprise caching product that can support
34   * all application sessions and/or provide disk paging for resilient data storage.
35   * <h2>Production Note</h2>
36   * This implementation defaults to using an in-memory map-based {@code CacheManager}, which is great for testing but
37   * will typically not scale for production environments and could easily cause {@code OutOfMemoryException}s.  Just
38   * don't forget to configure<b>*</b> an instance of this class with a production-grade {@code CacheManager} that can
39   * handle disk paging for large numbers of sessions and you'll be fine.
40   * <p/>
41   * <b>*</b>If you configure Shiro's {@code SecurityManager} instance with such a {@code CacheManager}, it will be
42   * automatically applied to an instance of this class and you won't need to explicitly set it in configuration.
43   * <h3>Implementation Details</h3>
44   * This implementation relies heavily on the {@link CachingSessionDAO parent class}'s transparent caching behavior for
45   * all storage operations with the enterprise caching product.  Because the parent class uses a {@code Cache} or
46   * {@code CacheManager} to perform caching, and the cache is considered the system of record, nothing further needs to
47   * be done for the {@link #doReadSession}, {@link #doUpdate} and {@link #doDelete} method implementations.  This class
48   * implements those methods as required by the parent class, but they essentially do nothing.
49   *
50   * @since 1.0
51   */
52  public class EnterpriseCacheSessionDAO extends CachingSessionDAO {
53  
54      public EnterpriseCacheSessionDAO() {
55          setCacheManager(new AbstractCacheManager() {
56              @Override
57              protected Cache<Serializable, Session> createCache(String name) throws CacheException {
58                  return new MapCache<Serializable, Session>(name, new ConcurrentHashMap<Serializable, Session>());
59              }
60          });
61      }
62  
63      protected Serializable doCreate(Session session) {
64          Serializable sessionId = generateSessionId(session);
65          assignSessionId(session, sessionId);
66          return sessionId;
67      }
68  
69      protected Session doReadSession(Serializable sessionId) {
70          return null; //should never execute because this implementation relies on parent class to access cache, which
71          //is where all sessions reside - it is the cache implementation that determines if the
72          //cache is memory only or disk-persistent, etc.
73      }
74  
75      protected void doUpdate(Session session) {
76          //does nothing - parent class persists to cache.
77      }
78  
79      protected void doDelete(Session session) {
80          //does nothing - parent class removes from cache.
81      }
82  }