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Java > Open Source Codes > org > apache > turbine > services > avaloncomponent > TurbineAvalonComponentService


1 package org.apache.turbine.services.avaloncomponent;
2
3 /*
4  * Copyright 2001-2004 The Apache Software Foundation.
5  *
6  * Licensed under the Apache License, Version 2.0 (the "License")
7  * you may not use this file except in compliance with the License.
8  * 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, software
13  * distributed under the License is distributed on an "AS IS" BASIS,
14  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15  * See the License for the specific language governing permissions and
16  * limitations under the License.
17  */
18
19 import java.util.Iterator JavaDoc;
20 import java.util.List JavaDoc;
21 import java.util.Vector JavaDoc;
22
23 import org.apache.commons.logging.Log;
24 import org.apache.commons.logging.LogFactory;
25
26 import org.apache.avalon.excalibur.component.DefaultRoleManager;
27 import org.apache.avalon.excalibur.component.ExcaliburComponentManager;
28 import org.apache.avalon.excalibur.logger.Log4JLoggerManager;
29 import org.apache.avalon.excalibur.logger.LoggerManager;
30 import org.apache.avalon.framework.activity.Disposable;
31 import org.apache.avalon.framework.activity.Initializable;
32 import org.apache.avalon.framework.component.Component;
33 import org.apache.avalon.framework.component.ComponentException;
34 import org.apache.avalon.framework.configuration.Configuration;
35 import org.apache.avalon.framework.configuration.DefaultConfigurationBuilder;
36 import org.apache.avalon.framework.context.DefaultContext;
37 import org.apache.avalon.framework.logger.Logger;
38
39 import org.apache.turbine.Turbine;
40 import org.apache.turbine.services.InitializationException;
41 import org.apache.turbine.services.TurbineBaseService;
42
43 /**
44  * An implementation of AvalonComponentService which loads all the
45  * components given in the TurbineResources.properties File.
46  * <p>
47  * For component which require the location of the application or
48  * context root, there are two ways to get it.
49  * <ol>
50  * <li>
51  * Implement the Contextualizable interface. The full path to the
52  * correct OS directory can be found under the ComponentAppRoot key.
53  * </li>
54  * <li>
55  * The system property "applicationRoot" is also set to the full path
56  * of the correct OS directory.
57  * </li>
58  * </ol>
59  * If you want to initialize Torque by using the AvalonComponentService, you
60  * must activate Torque at initialization time by specifying
61  *
62  * services.AvalonComponentService.lookup = org.apache.torque.Torque
63  *
64  * in your TurbineResources.properties.
65  *
66  * @author <a HREF="mailto:quintonm@bellsouth.net">Quinton McCombs</a>
67  * @author <a HREF="mailto:hps@intermeta.de">Henning P. Schmiedehausen</a>
68  * @version $Id: TurbineAvalonComponentService.java,v 1.17.2.3 2004/08/16 22:57:48 henning Exp $
69  */
70 public class TurbineAvalonComponentService
71         extends TurbineBaseService
72         implements AvalonComponentService, Initializable, Disposable
73 {
74     /** Logging */
75     private static Log log = LogFactory.getLog(
76             TurbineAvalonComponentService.class);
77
78     /** Component manager */
79     private ExcaliburComponentManager manager = null;
80
81     // -------------------------------------------------------------
82 // Service initialization
83 // -------------------------------------------------------------
84
85     /**
86      * Load all configured components and initialize them. This is
87      * a zero parameter variant which queries the Turbine Servlet
88      * for its config.
89      *
90      * @throws InitializationException Something went wrong in the init
91      * stage
92      */
93     public void init()
94             throws InitializationException
95     {
96         try
97         {
98             initialize();
99
100             setInit(true);
101         }
102         catch (Exception JavaDoc e)
103         {
104             throw new InitializationException("init failed", e);
105         }
106     }
107
108     /**
109      * Shuts the Component Service down, calls dispose on the components that
110      * implement this interface
111      *
112      */
113     public void shutdown()
114     {
115         dispose();
116         setInit(false);
117     }
118
119     // -------------------------------------------------------------
120 // Avalon lifecycle interfaces
121 // -------------------------------------------------------------
122
123     /**
124      * Initializes the container
125      *
126      * @throws Exception generic exception
127      */
128     public void initialize() throws Exception JavaDoc
129     {
130         org.apache.commons.configuration.Configuration conf
131                 = getConfiguration();
132
133         // get the filenames and expand them relative to webapp root
134 String JavaDoc sysConfigFilename = Turbine.getRealPath(
135                 conf.getString(COMPONENT_CONFIG_KEY, COMPONENT_CONFIG_VALUE));
136         String JavaDoc roleConfigFilename = Turbine.getRealPath(
137                 conf.getString(COMPONENT_ROLE_KEY, COMPONENT_ROLE_VALUE));
138
139         log.debug("Config File: " + sysConfigFilename);
140         log.debug("Role File: " + roleConfigFilename);
141
142         // process configuration files
143
144         DefaultConfigurationBuilder builder = new DefaultConfigurationBuilder();
145         Configuration sysConfig = builder.buildFromFile(sysConfigFilename);
146         Configuration roleConfig = builder.buildFromFile(roleConfigFilename);
147
148         // Create the LoggerManager for Log4J
149 LoggerManager lm = new Log4JLoggerManager();
150
151         // Setup the RoleManager
152 DefaultRoleManager roles = new DefaultRoleManager();
153
154         Logger logger = lm.getLoggerForCategory(AVALON_LOG_CATEGORY);
155
156         roles.enableLogging(logger);
157         roles.configure(roleConfig);
158
159         // Setup ECM
160 manager = new ExcaliburComponentManager();
161
162         manager.setLoggerManager(lm);
163         manager.enableLogging(logger);
164
165         DefaultContext context = new DefaultContext();
166         String JavaDoc realPath = Turbine.getRealPath("/");
167
168         context.put(AvalonComponentService.COMPONENT_APP_ROOT, realPath);
169         System.setProperty("applicationRoot", realPath);
170
171         log.debug("Application Root is " + realPath);
172
173         manager.contextualize(context);
174         manager.setRoleManager(roles);
175         manager.configure(sysConfig);
176
177         // Init ECM!!!!
178 manager.initialize();
179
180         List JavaDoc lookupComponents = conf.getList(COMPONENT_LOOKUP_KEY,
181                 new Vector JavaDoc());
182         
183         for (Iterator JavaDoc it = lookupComponents.iterator(); it.hasNext();)
184         {
185             String JavaDoc component = (String JavaDoc) it.next();
186             try
187             {
188                 Component c = manager.lookup(component);
189                 log.info("Lookup for Component " + component + " successful");
190                 manager.release(c);
191             }
192             catch (Exception JavaDoc e)
193             {
194                 log.error("Lookup for Component " + component + " failed!");
195             }
196         }
197     }
198
199     /**
200      * Disposes of the container and releases resources
201      */
202     public void dispose()
203     {
204         manager.dispose();
205     }
206
207     /**
208      * Returns an instance of the named component
209      *
210      * @param roleName Name of the role the component fills.
211      * @return an instance of the named component
212      * @throws ComponentException generic exception
213      */
214     public Component lookup(String JavaDoc roleName)
215             throws ComponentException
216     {
217         return manager.lookup(roleName);
218     }
219
220     /**
221      * Releases the component
222      *
223      * @param component the component to release
224      */
225     public void release(Component component)
226     {
227         manager.release(component);
228     }
229
230 }
231
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