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Java > Open Source Codes > org > apache > catalina > storeconfig > StoreLoader


1 /*
2  * Copyright 1999-2001,2004 The Apache Software Foundation.
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  * http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 package org.apache.catalina.storeconfig;
17
18 import java.io.File JavaDoc;
19 import java.io.FileInputStream JavaDoc;
20 import java.io.IOException JavaDoc;
21 import java.io.InputStream JavaDoc;
22 import java.net.URL JavaDoc;
23
24 import org.apache.commons.logging.Log;
25 import org.apache.commons.logging.LogFactory;
26 import org.apache.tomcat.util.digester.Digester;
27 import org.xml.sax.SAXException JavaDoc;
28
29 /**
30  *
31  * @author Peter Rossbach
32  *
33  * <b>XML Format </b>
34  *
35  * <pre>
36  *
37  * &lt;Registry name=&quot;&quot; encoding=&quot;UTF8&quot; &gt;
38  * &lt;Description tag=&quot;Server&quot; standard=&quot;true&quot; default=&quot;true&quot;/&gt;
39  * tagClass=&quot;org.apache.catalina.core.StandardServer&quot;
40  * storeFactory=&quot;org.apache.catalina.storeconfig.StandardServerSF&quot;&gt;
41  * &lt;TransientAttributes&gt;
42  * &lt;Attribute&gt;&lt;/Attribute&gt;
43  * &lt;/TransientAttributes&gt;
44  * &lt;TransientChilds&gt;
45  * &lt;Child&gt;&lt;/Child&gt;
46  * &lt;/TransientChilds&gt;
47  * &lt;/Description&gt;
48  * ...
49  * &lt;/Tegistry&gt;
50  *
51  * </pre>
52  *
53  *
54  * Convention:
55  * <ul>
56  * <li>Factories at subpackage <i>org.apache.catalina.core.storeconfig.xxxSF
57  * </i>.</li>
58  * <li>Element name are the unique Class name</li>
59  * <li>SF for StoreFactory</li>
60  * <li>standard implementation is false</li>
61  * </ul>
62  * other things:
63  * <ul>
64  * <li>Registry XML format is a very good option</li>
65  * <li>Store format is not fix</li>
66  * <li>We hope with the parent declaration we can build recursive child store
67  * operation //dream</li>
68  * <li>Problem is to access child data from array,collections or normal detail
69  * object</li>
70  * <li>Default definitions for Listener, Valve Resource? - Based on interface
71  * type!</li>
72  * </ul>
73  */
74 public class StoreLoader {
75     private static Log log = LogFactory.getLog(StoreLoader.class);
76
77     /**
78      * The <code>Digester</code> instance used to parse registry descriptors.
79      */
80     protected static Digester digester = createDigester();
81
82     private StoreRegistry registry;
83     
84     private URL JavaDoc registryResource ;
85
86     /**
87      * @return Returns the registry.
88      */
89     public StoreRegistry getRegistry() {
90         return registry;
91     }
92
93     /**
94      * @param registry
95      * The registry to set.
96      */
97     public void setRegistry(StoreRegistry registry) {
98         this.registry = registry;
99     }
100
101     /**
102      * Create and configure the Digester we will be using for setup store
103      * registry.
104      */
105     protected static Digester createDigester() {
106         long t1 = System.currentTimeMillis();
107         // Initialize the digester
108 Digester digester = new Digester();
109         digester.setValidating(false);
110         digester.setClassLoader(StoreRegistry.class.getClassLoader());
111
112         // Configure the actions we will be using
113 digester.addObjectCreate("Registry",
114                 "org.apache.catalina.storeconfig.StoreRegistry", "className");
115         digester.addSetProperties("Registry");
116         digester
117                 .addObjectCreate("Registry/Description",
118                         "org.apache.catalina.storeconfig.StoreDescription",
119                         "className");
120         digester.addSetProperties("Registry/Description");
121         digester.addRule("Registry/Description", new StoreFactoryRule(
122                 "org.apache.catalina.storeconfig.StoreFactoryBase",
123                 "storeFactoryClass",
124                 "org.apache.catalina.storeconfig.StoreAppender",
125                 "storeAppenderClass"));
126         digester.addSetNext("Registry/Description", "registerDescription",
127                 "org.apache.catalina.storeconfig.StoreDescription");
128         digester.addCallMethod("Registry/Description/TransientAttribute",
129                 "addTransientAttribute", 0);
130         digester.addCallMethod("Registry/Description/TransientChild",
131                 "addTransientChild", 0);
132
133         long t2 = System.currentTimeMillis();
134         if (log.isDebugEnabled())
135             log.debug("Digester for server-registry.xml created " + (t2 - t1));
136         return (digester);
137
138     }
139
140     /**
141      *
142      * @param aFile
143      * @return
144      */
145     protected File JavaDoc serverFile(String JavaDoc aFile) {
146
147         if (aFile == null || (aFile != null && aFile.length() < 1))
148             aFile = "server-registry.xml";
149         File JavaDoc file = new File JavaDoc(aFile);
150         if (!file.isAbsolute())
151             file = new File JavaDoc(System.getProperty("catalina.base") + "/conf",
152                     aFile);
153         try {
154             file = file.getCanonicalFile();
155         } catch (IOException JavaDoc e) {
156             log.error(e);
157         }
158         return (file);
159     }
160
161     /**
162      * Load Description from external source
163      *
164      * @param aURL
165      */
166     public void load(String JavaDoc aURL) {
167         synchronized (digester) {
168             File JavaDoc aRegistryFile = serverFile(aURL);
169             try {
170                 registry = (StoreRegistry) digester.parse(aRegistryFile);
171                 registryResource = aRegistryFile.toURL();
172             } catch (IOException JavaDoc e) {
173                 log.error(e);
174             } catch (SAXException JavaDoc e) {
175                 log.error(e);
176             }
177         }
178
179     }
180
181     /**
182      * Load from defaults
183      * <ul>
184      * <li>System Property URL catalina.storeregistry</li>
185      * <li>File $catalina.base/conf/server-registry.xml</li>
186      * <li>class resource org/apache/catalina/storeconfig/server-registry.xml
187      * </li>
188      * </ul>
189      */
190     public void load() {
191
192         InputStream JavaDoc is = null;
193         Throwable JavaDoc error = null;
194         registryResource = null ;
195         try {
196             String JavaDoc configUrl = getConfigUrl();
197             if (configUrl != null) {
198                 is = (new URL JavaDoc(configUrl)).openStream();
199                 if (log.isInfoEnabled())
200                     log
201                             .info("Find registry server-registry.xml from system property at url "
202                                     + configUrl);
203                 ;
204                 registryResource = new URL JavaDoc(configUrl);
205             }
206         } catch (Throwable JavaDoc t) {
207             // Ignore
208 }
209         if (is == null) {
210             try {
211                 File JavaDoc home = new File JavaDoc(getCatalinaBase());
212                 File JavaDoc conf = new File JavaDoc(home, "conf");
213                 File JavaDoc reg = new File JavaDoc(conf, "server-registry.xml");
214                 is = new FileInputStream JavaDoc(reg);
215                 if (log.isInfoEnabled())
216                     log.info("Find registry server-registry.xml at file "
217                             + reg.getCanonicalPath());
218                 ;
219                 registryResource = reg.toURL() ;
220             } catch (Throwable JavaDoc t) {
221                 // Ignore
222 }
223         }
224         if (is == null) {
225             try {
226                 is = StoreLoader.class
227                         .getResourceAsStream("/org/apache/catalina/storeconfig/server-registry.xml");
228                 if (log.isInfoEnabled())
229                     log
230                             .info("Find registry server-registry.xml at classpath resource");
231                 registryResource = StoreLoader.class
232                     .getResource("/org/apache/catalina/storeconfig/server-registry.xml");
233                 
234             } catch (Throwable JavaDoc t) {
235                 // Ignore
236 }
237         }
238         if (is != null) {
239             try {
240                 synchronized (digester) {
241                     registry = (StoreRegistry) digester.parse(is);
242                 }
243             } catch (Throwable JavaDoc t) {
244                 error = t;
245             } finally {
246                 try {
247                     is.close();
248                 } catch (IOException JavaDoc e) {
249                 }
250             }
251         }
252         if ((is == null) || (error != null)) {
253             log.error(error);
254         }
255     }
256
257     /**
258      * Get the value of the catalina.home environment variable.
259      */
260     private static String JavaDoc getCatalinaHome() {
261         return System.getProperty("catalina.home", System
262                 .getProperty("user.dir"));
263     }
264
265     /**
266      * Get the value of the catalina.base environment variable.
267      */
268     private static String JavaDoc getCatalinaBase() {
269         return System.getProperty("catalina.base", getCatalinaHome());
270     }
271
272     /**
273      * Get the value of the configuration URL.
274      */
275     private static String JavaDoc getConfigUrl() {
276         return System.getProperty("catalina.storeconfig");
277     }
278     
279     
280
281     /**
282      * @return Returns the registryResource.
283      */
284     public URL JavaDoc getRegistryResource() {
285         return registryResource;
286     }
287 }
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