2009/05/20 - Apache Shale has been retired.

For more information, please explore the Attic.


1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to you under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *      http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   *
17   * $Id: Application.java 464373 2006-10-16 04:21:54Z rahul $
18   */
19  
20  package org.apache.shale.examples.sqlbrowser;
21  
22  import java.util.ArrayList;
23  import java.util.List;
24  import javax.faces.FacesException;
25  import javax.faces.context.FacesContext;
26  import javax.faces.model.SelectItem;
27  import javax.naming.Context;
28  import javax.naming.InitialContext;
29  import javax.naming.NameClassPair;
30  import javax.naming.NamingEnumeration;
31  import javax.sql.DataSource;
32  import org.apache.shale.tiger.managed.Bean;
33  import org.apache.shale.tiger.managed.Scope;
34  
35  /***
36   * <p>Application scope managed bean for the SQL Browser application.</p>
37   */
38  @Bean(name="appbean", scope=Scope.APPLICATION)
39  public class Application {
40      
41  
42      public Application() {
43          System.err.println("Application constructor()");
44      }
45  
46  
47      // ------------------------------------------------------ Manifest Constants
48  
49  
50      /***
51       * <p>The prefix of the JNDI name for all relevant data sources.</p>
52       */
53      private static final String PREFIX = "java:comp/env";
54  
55  
56      // ------------------------------------------------------ Instance Variables
57  
58  
59      /***
60       * <p>The list of <code>DataSource</code>s available via JNDI for this
61       * web application.</p>
62       */
63      private SelectItem[] dataSources = null;
64  
65  
66      // ---------------------------------------------------------- Public Methods
67  
68  
69      /***
70       * <p>Return the list of <code>DataSource</code>s available via JNDI
71       * for this web application.</p>
72       */
73      public SelectItem[] getDataSources() {
74  
75          System.err.println("Application getDataSources()");
76          if (dataSources == null) {
77              List<SelectItem> list = new ArrayList<SelectItem>();
78              internal(list);
79              try {
80                  InitialContext context = new InitialContext();
81                  append(context, PREFIX, list);
82              } catch (Exception e) {
83                  throw new FacesException(e);
84              }
85              dataSources = (SelectItem[]) list.toArray(new SelectItem[list.size()]);
86          }
87          System.err.println("Application getDataSources() --> " + dataSources.length);
88          return dataSources;
89  
90      }
91  
92  
93      // --------------------------------------------------------- Private Methods
94  
95  
96      /***
97       * <p>Append any data sources found in the specified JNDI context
98       * to the specified list.  If a JNDI subcontext is found, apply this
99       * method recursively.</p>
100      *
101      * @param context JNDI context to be searched
102      * @param prefix Prefix for the fully qualified resource names to be added
103      * @param list List of data sources to which new ones should be added
104      */
105     private void append(Context context, String prefix, List<SelectItem> list) {
106 
107         ClassLoader cl = Thread.currentThread().getContextClassLoader();
108         if (cl == null) {
109             cl = Application.class.getClassLoader();
110         }
111         try {
112             NamingEnumeration<NameClassPair> entries = context.list(prefix);
113             while (entries.hasMore()) {
114                 NameClassPair entry = entries.next();
115                 Class clazz = cl.loadClass(entry.getClassName());
116                 if (DataSource.class.isAssignableFrom(clazz)) {
117                     list.add(new SelectItem(prefix + "/" + entry.getName(),
118                                             (prefix + "/" + entry.getName()).substring(PREFIX.length())));
119                 } else if (Context.class.isAssignableFrom(clazz)) {
120                     Context search = (Context) context.lookup(entry.getName());
121                     append(search, prefix + "/" + entry.getName(), list);
122                 }
123             }
124         } catch (Exception e) {
125             throw new FacesException(e);
126         }
127 
128     }
129 
130 
131     /***
132      * <p>Append the default internal data source for this application.</p>
133      *
134      * @param list List of <code>SelectItem</code> of available data sources
135      */
136     private void internal(List<SelectItem> list) {
137 
138         FacesContext context = FacesContext.getCurrentInstance();
139         // FIXME - localize the label
140         list.add(new SelectItem("", "(Internal)"));
141 
142     }
143 
144 
145 }