AbsModuleClassLoader


1   /**
2    * JOnAS: Java(TM) Open Application Server
3    * Copyright (C) 1999 Bull S.A.
4    * Contact: jonas-team@objectweb.org
5    *
6    * This library is free software; you can redistribute it and/or
7    * modify it under the terms of the GNU Lesser General Public
8    * License as published by the Free Software Foundation; either
9    * version 2.1 of the License, or any later version.
10   *
11   * This library is distributed in the hope that it will be useful,
12   * but WITHOUT ANY WARRANTY; without even the implied warranty of
13   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14   * Lesser General Public License for more details.
15   *
16   * You should have received a copy of the GNU Lesser General Public
17   * License along with this library; if not, write to the Free Software
18   * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
19   * USA
20   *
21   * Initial developer(s): Guillaume SAUTHIER
22   * --------------------------------------------------------------------------
23   * $Id: AbsModuleClassLoader.java,v 1.6 2004/12/16 16:09:11 sauthieg Exp $
24   * --------------------------------------------------------------------------
25   */
26  
27  package org.objectweb.jonas_lib.loader;
28  
29  import java.io.File  ;
30  import java.io.IOException  ;
31  import java.net.URL  ;
32  import java.net.URLClassLoader  ;
33  import java.util.List  ;
34  import java.util.Iterator  ;
35  
36  import org.objectweb.jonas_lib.loader.factory.URLFactory;
37  import org.objectweb.jonas_lib.loader.locator.Locator;
38  
39  /**
40   * The <code>AbsModuleClassLoader</code> class is used in JOnAS
41   * for loading web, ejbjars and client modules.
42   *
43   * @author Guillaume Sauthier
44   */
45  public abstract class AbsModuleClassLoader extends URLClassLoader   {
46  
47      /** factories used to create URLs for URLClassLoader */
48      private URLFactory[] factories;
49  
50      /** locators used to search jar/dir for files, directories, ... */
51      private Locator[] locators;
52  
53      /** bases URLs */
54      private URL  [] bases;
55  
56      /**
57       * Create a new AbsModuleClassLoader for a list of URLs.
58       *
59       * @param modules the list of URL to be used in the ClassLoader.
60       *
61       * @throws IOException when Initialization fails.
62       */
63      public AbsModuleClassLoader(URL  [] modules) throws IOException   {
64          super(new URL  [0]);
65          bases = modules;
66          init();
67      }
68  
69      /**
70       * Create a new AbsModuleClassLoader for a list of URLs with a specified parent loader.
71       *
72       * @param modules the list of URL to be used in the ClassLoader.
73       * @param parent the parent ClassLoader to be used.
74       *
75       * @throws IOException when Initialization fails.
76       */
77      public AbsModuleClassLoader(URL  [] modules, ClassLoader   parent) throws IOException   {
78          super(new URL  [0], parent);
79          bases = modules;
80          init();
81      }
82  
83      /**
84       * Base Initialization of the ClassLoader, storage of URL list.
85       *
86       * @throws IOException when URL pointed file is not supported (not an jar nor a directory).
87       */
88      protected void init() throws IOException   {
89          factories = new URLFactory[bases.length];
90          locators = new Locator[bases.length];
91  
92          // Create factories and locator for each URL
93          for (int i = 0; i < bases.length; i++) {
94  
95              factories[i] = URLFactory.getFactory(bases[i]);
96              locators[i] = Locator.getLocator(bases[i]);
97          }
98      }
99  
100     /**
101      * Add specified location into the repository.
102      * If location is found in multiple URLs of the bases, new
103      * URLs will be added multiple times.
104      *
105      * @param location an entry name (for a jar) or a path name (for a directory)
106      *
107      * @throws IOException when constructed URL is malformed
108      */
109     protected void addInRepository(String   location) throws IOException   {
110         // test existence in each base URL
111         for (int i = 0; i < bases.length; i++) {
112             if (locators[i].hasDirectory(location)
113                 || locators[i].hasFile(location)) {
114                 addURL(factories[i].getURL(location));
115             }
116         }
117     }
118 
119     /**
120      * Add specified location childs into the repository.
121      * Search will be performed on the bases URLs.
122      *
123      * @param location an entry name (for a jar) or a path name (for a directory)
124      *
125      * @throws IOException When a directory content cannot be explored.
126      *
127      * TODO test existence is now done in AbsModuleClassLoader
128      */
129     protected void addContentInRepository(String   location) throws IOException   {
130         // test existence in each base URL
131         for (int i = 0; i < bases.length; i++) {
132             List   list = locators[i].listContent(location);
133             for (Iterator   l = list.iterator(); l.hasNext();) {
134                 addURL(factories[i].getURL((String  ) l.next()));
135             }
136         }
137     }
138 
139     /**
140      * @return Returns a String representation of the AbsModuleClassLoader
141      */
142     public String   toString() {
143         StringBuffer   sb = new StringBuffer  ();
144 
145         sb.append("classloader : " + getClass().getName() + "\n");
146         sb.append("\tmodules bases (not in loader!) : \n");
147         for (int i = 0; i < bases.length; i++) {
148             sb.append("\t\t -" + bases[i] + "\n");
149         }
150         sb.append("\trepositories :\n");
151         URL  [] rep = getURLs();
152         for (int i = 0; i < rep.length; i++) {
153             sb.append("\t\t -" + rep[i] + "\n");
154         }
155         sb.append("\tparent : " + getParent() + "\n");
156 
157         return sb.toString();
158     }
159 
160     /**
161      * @return Returns the bases.
162      */
163     public URL  [] getBases() {
164         return bases;
165     }
166 
167     /**
168      * @return Returns a String representation of the classpath used by this classloader
169      */
170     public String   getClasspath() {
171         URL  [] urls = getURLs();
172         StringBuffer   cp = new StringBuffer  ();
173         for (int i = 0; i < urls.length; i++) {
174             String   url = urls[i].getFile();
175             // do not add URL with !/ inside
176             if (url.indexOf("!/") == -1) {
177                 cp.append(File.pathSeparator + url);
178             }
179         }
180         return  cp.toString();
181     }
182 }
183
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