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1   package org.apache.turbine.services;
2   
3   /*
4    * Licensed to the Apache Software Foundation (ASF) under one
5    * or more contributor license agreements.  See the NOTICE file
6    * distributed with this work for additional information
7    * regarding copyright ownership.  The ASF licenses this file
8    * to you under the Apache License, Version 2.0 (the
9    * "License"); you may not use this file except in compliance
10   * with the License.  You may obtain a copy of the License at
11   *
12   *   http://www.apache.org/licenses/LICENSE-2.0
13   *
14   * Unless required by applicable law or agreed to in writing,
15   * software distributed under the License is distributed on an
16   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17   * KIND, either express or implied.  See the License for the
18   * specific language governing permissions and limitations
19   * under the License.
20   */
21  
22  import javax.servlet.ServletConfig;
23  
24  import org.apache.turbine.util.RunData;
25  
26  /***
27   * <p>This class provides a <code>Service</code> implementation that
28   * Services used in Turbine are required to extend.  The
29   * functionality provided in addition to <code>BaseService</code>
30   * functionality is recognizing objects used in early initialization
31   * of <code>Services</code> in Turbine, and passing them to
32   * appropriate convenience methods.  These methods should be overriden
33   * to provide desired initialization functionality.</p>
34   *
35   * <p><strong>Note!</strong><br>Remember to call
36   * <code>setInit(true)</code> after successful initialization.</p>
37   *
38   * <p><strong>Note!</strong><br>If you need to use another
39   * <code>Service</code> inside your early initialization, remember to
40   * request initialization of that <code>Service</code> before using
41   * it:</p>
42   *
43   * <pre><code>
44   * getServiceBroker().initClass("OtherService",data);
45   * OtherService service =
46   *         (OtherService)getServiceBroker().getService("OtherService");
47   * </code></pre>
48   *
49   * @author <a href="mailto:greg@shwoop.com">Greg Ritter</a>
50   * @author <a href="mailto:bmclaugh@algx.net">Brett McLaughlin</a>
51   * @author <a href="mailto:burton@apache.org">Kevin Burton</a>
52   * @author <a href="mailto:krzewski@e-point.pl">Rafal Krzewski</a>
53   * @author <a href="mailto:jon@latchkey.com">Jon S. Stevens</a>
54   * @author <a href="mailto:jvanzyl@periapt.com">Jason van Zyl</a>
55   * @version $Id: TurbineBaseService.java 534527 2007-05-02 16:10:59Z tv $
56   */
57  public abstract class TurbineBaseService
58          extends BaseService
59  {
60      /***
61       * Performs early initialization.  Overrides init() method in
62       * BaseService to detect objects used in Turbine's Service
63       * initialization and pass them to apropriate init() methods.
64       *
65       * @param data An Object to use for initialization activities.
66       * @exception InitializationException if initialization of this
67       * class was not successful.
68       */
69      public void init(Object data)
70              throws InitializationException
71      {
72          if (data instanceof ServletConfig)
73          {
74              init((ServletConfig) data);
75          }
76          else if (data instanceof RunData)
77          {
78              init((RunData) data);
79          }
80      }
81  
82      /***
83       * Performs early initialization.
84       *
85       * @param config A ServletConfing to use for initialization
86       * activities.
87       * @exception InitializationException if initialization of this
88       * class was not successful.
89       * @deprecated Use init() instead
90       */
91      public void init(ServletConfig config) throws InitializationException
92      {
93      }
94  
95      /***
96       * Performs early initialization.
97       *
98       * @param data An RunData to use for initialization activities.
99       * @exception InitializationException if initialization of this
100      * class was not successful.
101      */
102     public void init(RunData data) throws InitializationException
103     {
104     }
105 
106     /***
107      * Performs late initialization.
108      *
109      * If your class relies on early initialization, and the object it
110      * expects was not received, you can use late initialization to
111      * throw an exception and complain.
112      *
113      * @exception InitializationException, if initialization of this
114      * class was not successful.
115      */
116     public void init() throws InitializationException
117     {
118         setInit(true);
119     }
120 
121     /***
122      * Returns to uninitialized state.
123      *
124      * You can use this method to release resources thet your Service
125      * allocated when Turbine shuts down.
126      */
127     public void shutdown()
128     {
129         setInit(false);
130     }
131 }