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Java > Open Source Codes > com > sun > org > apache > bcel > internal > util > SyntheticRepository


1 package com.sun.org.apache.bcel.internal.util;
2
3 /* ====================================================================
4  * The Apache Software License, Version 1.1
5  *
6  * Copyright (c) 2001 The Apache Software Foundation. All rights
7  * reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  *
13  * 1. Redistributions of source code must retain the above copyright
14  * notice, this list of conditions and the following disclaimer.
15  *
16  * 2. Redistributions in binary form must reproduce the above copyright
17  * notice, this list of conditions and the following disclaimer in
18  * the documentation and/or other materials provided with the
19  * distribution.
20  *
21  * 3. The end-user documentation included with the redistribution,
22  * if any, must include the following acknowledgment:
23  * "This product includes software developed by the
24  * Apache Software Foundation (http://www.apache.org/)."
25  * Alternately, this acknowledgment may appear in the software itself,
26  * if and wherever such third-party acknowledgments normally appear.
27  *
28  * 4. The names "Apache" and "Apache Software Foundation" and
29  * "Apache BCEL" must not be used to endorse or promote products
30  * derived from this software without prior written permission. For
31  * written permission, please contact apache@apache.org.
32  *
33  * 5. Products derived from this software may not be called "Apache",
34  * "Apache BCEL", nor may "Apache" appear in their name, without
35  * prior written permission of the Apache Software Foundation.
36  *
37  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
38  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
39  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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41  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
42  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
43  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
44  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
45  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
46  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
47  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
48  * SUCH DAMAGE.
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50  *
51  * This software consists of voluntary contributions made by many
52  * individuals on behalf of the Apache Software Foundation. For more
53  * information on the Apache Software Foundation, please see
54  * <http://www.apache.org/>.
55  */
56
57 import java.io.*;
58
59 import java.util.Map JavaDoc;
60 import java.util.HashMap JavaDoc;
61
62 import com.sun.org.apache.bcel.internal.classfile.*;
63
64 /**
65  * This repository is used in situations where a Class is created
66  * outside the realm of a ClassLoader. Classes are loaded from
67  * the file systems using the paths specified in the given
68  * class path. By default, this is the value returned by
69  * ClassPath.getClassPath().
70  * <br>
71  * It is designed to be used as a singleton, however it
72  * can also be used with custom classpaths.
73  *
74 /**
75  * Abstract definition of a class repository. Instances may be used
76  * to load classes from different sources and may be used in the
77  * Repository.setRepository method.
78  *
79  * @see com.sun.org.apache.bcel.internal.Repository
80  *
81  * @version $Id: SyntheticRepository.java,v 1.1.2.1 2005/07/31 23:47:04 jeffsuttor Exp $
82  * @author <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A>
83  * @author David Dixon-Peugh
84  */
85 public class SyntheticRepository implements Repository {
86   private static final String JavaDoc DEFAULT_PATH = ClassPath.getClassPath();
87
88   private static HashMap JavaDoc _instances = new HashMap JavaDoc(); // CLASSPATH X REPOSITORY
89
90   private ClassPath _path = null;
91   private HashMap JavaDoc _loadedClasses = new HashMap JavaDoc(); // CLASSNAME X JAVACLASS
92
93   private SyntheticRepository(ClassPath path) {
94     _path = path;
95   }
96
97   public static SyntheticRepository getInstance() {
98     return getInstance(ClassPath.SYSTEM_CLASS_PATH);
99   }
100
101   public static SyntheticRepository getInstance(ClassPath classPath) {
102     SyntheticRepository rep = (SyntheticRepository)_instances.get(classPath);
103
104     if(rep == null) {
105       rep = new SyntheticRepository(classPath);
106       _instances.put(classPath, rep);
107     }
108
109     return rep;
110   }
111
112   /**
113    * Store a new JavaClass instance into this Repository.
114    */
115   public void storeClass(JavaClass clazz) {
116     _loadedClasses.put(clazz.getClassName(), clazz);
117     clazz.setRepository(this);
118  }
119
120   /**
121    * Remove class from repository
122    */
123   public void removeClass(JavaClass clazz) {
124     _loadedClasses.remove(clazz.getClassName());
125   }
126
127   /**
128    * Find an already defined (cached) JavaClass object by name.
129    */
130   public JavaClass findClass(String JavaDoc className) {
131     return (JavaClass)_loadedClasses.get(className);
132   }
133
134   /**
135    * Load a JavaClass object for the given class name using
136    * the CLASSPATH environment variable.
137    */
138   public JavaClass loadClass(String JavaDoc className)
139     throws ClassNotFoundException JavaDoc
140   {
141     if(className == null || className.equals("")) {
142       throw new IllegalArgumentException JavaDoc("Invalid class name " + className);
143     }
144
145     className = className.replace('/', '.'); // Just in case, canonical form
146
147     try {
148       return loadClass(_path.getInputStream(className), className);
149     } catch(IOException e) {
150       throw new ClassNotFoundException JavaDoc("Exception while looking for class " +
151                        className + ": " + e.toString());
152     }
153   }
154
155   /**
156    * Try to find class source via getResourceAsStream().
157    * @see Class
158    * @return JavaClass object for given runtime class
159    */
160   public JavaClass loadClass(Class JavaDoc clazz) throws ClassNotFoundException JavaDoc {
161     String JavaDoc className = clazz.getName();
162     String JavaDoc name = className;
163     int i = name.lastIndexOf('.');
164
165     if(i > 0) {
166       name = name.substring(i + 1);
167     }
168
169     return loadClass(clazz.getResourceAsStream(name + ".class"), className);
170   }
171
172   private JavaClass loadClass(InputStream is, String JavaDoc className)
173     throws ClassNotFoundException JavaDoc
174   {
175     JavaClass clazz = findClass(className);
176
177     if(clazz != null) {
178       return clazz;
179     }
180
181     try {
182       if(is != null) {
183     ClassParser parser = new ClassParser(is, className);
184     clazz = parser.parse();
185     
186     storeClass(clazz);
187     
188     return clazz;
189       }
190     } catch(IOException e) {
191       throw new ClassNotFoundException JavaDoc("Exception while looking for class " +
192                        className + ": " + e.toString());
193     }
194
195     throw new ClassNotFoundException JavaDoc("SyntheticRepository could not load " +
196                      className);
197   }
198
199   /** Clear all entries from cache.
200    */
201   public void clear() {
202     _loadedClasses.clear();
203   }
204 }
205
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