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1
10
11 package org.mule.registry;
12
13 import java.io.File  ;
14 import java.net.MalformedURLException ;
15 import java.net.URL ;
16 import java.net.URLClassLoader ;
17 import java.security.SecureClassLoader ;
18 import java.util.ArrayList ;
19 import java.util.HashMap ;
20 import java.util.Iterator ;
21 import java.util.List ;
22 import java.util.Map ;
23
24
27 public class ClassLoaderFactory
28 {
29
30 private static ClassLoaderFactory factory;
31 private Map sharedClassLoaders;
32
33 public static ClassLoaderFactory getInstance()
34 {
35 if (factory == null)
36 {
37 factory = new ClassLoaderFactory();
38 }
39 return factory;
40 }
41
42 private ClassLoaderFactory()
43 {
44 this.sharedClassLoaders = new HashMap ();
45 }
46
47 public ClassLoader createComponentClassLoader(RegistryComponent component) throws MalformedURLException
48 {
49 DelegatingClassLoader dcl = new DelegatingClassLoader();
50 Library[] libraries = component.getLibraries();
51 for (int i = 0; i < libraries.length; i++)
52 {
53 dcl.addClassLoader(getSharedClassLoader(libraries[i]));
54 }
55 URL [] urls = getUrlsFrom(component.getInstallRoot(), component.getClassPathElements());
56 boolean isParentFirst = component.isClassLoaderParentFirst();
57 JbiClassLoader ccl = new JbiClassLoader(urls, dcl, isParentFirst);
58 return ccl;
59 }
60
61 private ClassLoader getSharedClassLoader(Library library) throws MalformedURLException
62 {
63 ClassLoader cl = (ClassLoader )this.sharedClassLoaders.get(library.getName());
64 if (cl == null)
65 {
66 URL [] urls = getUrlsFrom(library.getInstallRoot(), library.getClassPathElements());
67 boolean isParentFirst = library.isClassLoaderParentFirst();
68 cl = new JbiClassLoader(urls, null, isParentFirst);
69 this.sharedClassLoaders.put(library.getName(), cl);
70 }
71 return cl;
72 }
73
74 private URL [] getUrlsFrom(String root, List paths) throws MalformedURLException
75 {
76 URL [] urls = new URL [paths.size()];
77 for (int i = 0; i < urls.length; i++)
78 {
79 String cpElement = (String )paths.get(i);
80 urls[i] = new File (root, cpElement).toURL();
81 }
82 return urls;
83 }
84
85
91 public static class JbiClassLoader extends URLClassLoader
92 {
93
94 private boolean parentFirst;
95
96 public JbiClassLoader(URL [] urls, ClassLoader parent, boolean parentFirst)
97 {
98 super(urls, parent);
99 this.parentFirst = parentFirst;
100 }
101
102 protected synchronized Class loadClass(String name, boolean resolve) throws ClassNotFoundException
103 {
104 Class clazz = findLoadedClass(name);
106 if (clazz == null)
107 {
108 if (this.parentFirst)
109 {
110 try
111 {
112 clazz = getParent().loadClass(name);
113 }
114 catch (ClassNotFoundException cnfe)
115 {
116 clazz = findClass(name);
117 }
118 }
119 else
120 {
121 try
122 {
123 clazz = findClass(name);
124 }
125 catch (ClassNotFoundException e)
126 {
127 clazz = getParent().loadClass(name);
128 }
129 }
130 }
131 if (resolve)
132 {
133 resolveClass(clazz);
134 }
135 return clazz;
136 }
137 }
138
139
144 public static class DelegatingClassLoader extends SecureClassLoader
145 {
146 private List loaders;
147
148 public DelegatingClassLoader()
149 {
150 this.loaders = new ArrayList ();
151 }
152
153 public void addClassLoader(ClassLoader loader)
154 {
155 if (loader == null)
156 {
157 throw new IllegalArgumentException ("loader can not be null");
158 }
159 loaders.add(loader);
160 }
161
162 protected Class findClass(String name) throws ClassNotFoundException
163 {
164 for (Iterator iter = this.loaders.iterator(); iter.hasNext();)
165 {
166 ClassLoader loader = (ClassLoader )iter.next();
167 try
168 {
169 return loader.loadClass(name);
170 }
171 catch (ClassNotFoundException e)
172 {
173 }
175 }
176 throw new ClassNotFoundException (name);
177 }
178 }
179
180 }
181 |
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