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1   package org.apache.turbine.services;
2   
3   
4   /*
5    * Licensed to the Apache Software Foundation (ASF) under one
6    * or more contributor license agreements.  See the NOTICE file
7    * distributed with this work for additional information
8    * regarding copyright ownership.  The ASF licenses this file
9    * to you under the Apache License, Version 2.0 (the
10   * "License"); you may not use this file except in compliance
11   * with the License.  You may obtain a copy of the License at
12   *
13   *   http://www.apache.org/licenses/LICENSE-2.0
14   *
15   * Unless required by applicable law or agreed to in writing,
16   * software distributed under the License is distributed on an
17   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
18   * KIND, either express or implied.  See the License for the
19   * specific language governing permissions and limitations
20   * under the License.
21   */
22  
23  
24  import org.apache.turbine.pipeline.PipelineData;
25  import org.apache.turbine.util.RunData;
26  
27  /**
28   * <p>This class provides a <code>Service</code> implementation that
29   * Services used in Turbine are required to extend.  The
30   * functionality provided in addition to <code>BaseService</code>
31   * functionality is recognizing objects used in early initialization
32   * of <code>Services</code> in Turbine, and passing them to
33   * appropriate convenience methods.  These methods should be overriden
34   * to provide desired initialization functionality.</p>
35   *
36   * <p><strong>Note!</strong><br>Remember to call
37   * <code>setInit(true)</code> after successful initialization.</p>
38   *
39   * <p><strong>Note!</strong><br>If you need to use another
40   * <code>Service</code> inside your early initialization, remember to
41   * request initialization of that <code>Service</code> before using
42   * it:</p>
43   *
44   * <pre><code>
45   * getServiceBroker().initClass("OtherService",data);
46   * OtherService service =
47   *         (OtherService)getServiceBroker().getService("OtherService");
48   * </code></pre>
49   *
50   * @author <a href="mailto:greg@shwoop.com">Greg Ritter</a>
51   * @author <a href="mailto:bmclaugh@algx.net">Brett McLaughlin</a>
52   * @author <a href="mailto:burton@apache.org">Kevin Burton</a>
53   * @author <a href="mailto:krzewski@e-point.pl">Rafal Krzewski</a>
54   * @author <a href="mailto:jon@latchkey.com">Jon S. Stevens</a>
55   * @author <a href="mailto:jvanzyl@periapt.com">Jason van Zyl</a>
56   * @author <a href="mailto:peter@courcoux.biz">Peter Courcoux</a>
57   * @version $Id: TurbineBaseService.java 1078552 2011-03-06 19:58:46Z tv $
58   */
59  public abstract class TurbineBaseService
60          extends BaseService
61  {
62      /**
63       * Performs early initialization.  Overrides init() method in
64       * BaseService to detect objects used in Turbine's Service
65       * initialization and pass them to apropriate init() methods.
66       *
67       * @param data An Object to use for initialization activities.
68       * @exception InitializationException if initialization of this
69       * class was not successful.
70       */
71      @Override
72      public void init(Object data)
73              throws InitializationException
74      {
75          if (data instanceof RunData)
76          {
77              init((RunData) data);
78          }
79          else if (data instanceof PipelineData)
80          {
81              init((PipelineData) data);
82          }
83      }
84  
85      /**
86       * Performs early initialization.
87       *
88       * @deprecated Use the PipelineData version instead.
89       * @param data An RunData to use for initialization activities.
90       * @exception InitializationException if initialization of this
91       * class was not successful.
92       */
93      @Deprecated
94      public void init(RunData data) throws InitializationException
95      {
96          // empty
97      }
98  
99      /**
100      * Performs early initialization.
101      *
102      * @param data A PipelineData to use for initialization activities.
103      * @exception InitializationException if initialization of this
104      * class was not successful.
105      */
106     public void init(PipelineData data) throws InitializationException
107     {
108         // empty
109     }
110 
111 
112     /**
113      * Performs late initialization.
114      *
115      * If your class relies on early initialization, and the object it
116      * expects was not received, you can use late initialization to
117      * throw an exception and complain.
118      *
119      * @exception InitializationException, if initialization of this
120      * class was not successful.
121      */
122     @Override
123     public void init() throws InitializationException
124     {
125         setInit(true);
126     }
127 
128     /**
129      * Returns to uninitialized state.
130      *
131      * You can use this method to release resources thet your Service
132      * allocated when Turbine shuts down.
133      */
134     @Override
135     public void shutdown()
136     {
137         setInit(false);
138     }
139 }