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1   package org.apache.turbine.pipeline;
2   
3   import java.util.HashMap;
4   import java.util.Map;
5   
6   
7   /*
8    * Licensed to the Apache Software Foundation (ASF) under one
9    * or more contributor license agreements.  See the NOTICE file
10   * distributed with this work for additional information
11   * regarding copyright ownership.  The ASF licenses this file
12   * to you under the Apache License, Version 2.0 (the
13   * "License"); you may not use this file except in compliance
14   * with the License.  You may obtain a copy of the License at
15   *
16   *   http://www.apache.org/licenses/LICENSE-2.0
17   *
18   * Unless required by applicable law or agreed to in writing,
19   * software distributed under the License is distributed on an
20   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
21   * KIND, either express or implied.  See the License for the
22   * specific language governing permissions and limitations
23   * under the License.
24   */
25  
26  
27  /**
28   * <p>A <b>PipelineData</b> is a holder for data being passed from one
29   * Valve to the next.
30   * The detailed contract for a Valve is included in the description of
31   * the <code>invoke()</code> method below.</p>
32   *
33   * <b>HISTORICAL NOTE</b>:  The "PipelineData" name was assigned to this
34   * holder as it functions similarly to the RunData object, but without
35   * the additional methods
36   *
37   * @author <a href="mailto:epugh@opensourceconnections.com">Eric Pugh</a>
38   * @author <a href="mailto:peter@courcoux.biz">Peter Courcoux</a>
39   */
40  public class DefaultPipelineData implements PipelineData
41  {
42      private final Map<Class<?>, Map<Class<?>, ? super Object>> map =
43          new HashMap<Class<?>, Map<Class<?>, ? super Object>>();
44  
45      /**
46       * Put a configured map of objects into the pipeline data object
47       *
48       * @param key the key class
49       * @param value the value map
50       */
51      @Override
52      public void put(Class<?> key, Map<Class<?>, ? super Object> value)
53      {
54          map.put(key, value);
55      }
56  
57      /**
58       * Get the configured map of objects for the given key
59       *
60       * @param key the key class
61       * @return the value map or null if no such key exists
62       */
63      @Override
64      public Map<Class<?>, ? super Object> get(Class<?> key)
65      {
66          return map.get(key);
67      }
68  
69      /**
70       * Get a value from the configured map of objects for the given keys
71       *
72       * @param key the key class
73       * @param innerKey the key into the value map
74       * @return the inner value or null if no such keys exist
75       */
76      @Override
77      @SuppressWarnings("unchecked")
78      public <T> T get(Class<?> key, Class<T> innerKey)
79      {
80          Map<Class<?>, ? super Object> innerMap = get(key);
81          if (innerMap == null)
82          {
83              return null;
84          }
85          return (T) innerMap.get(innerKey);
86      }
87  }