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1
12 package org.eclipse.ant.internal.core;
13
14
15 import java.io.IOException  ;
16 import java.net.URL ;
17 import java.net.URLClassLoader ;
18 import java.util.ArrayList ;
19 import java.util.Collections ;
20 import java.util.Enumeration ;
21 import java.util.List ;
22
23 public class AntClassLoader extends URLClassLoader {
24
25 private static final String ANT_PACKAGES_PREFIX = "org.apache.tools"; private static final String ANT_URL_PREFIX = "org/apache/tools";
28 private boolean fAllowPluginLoading = false;
29
30 protected ClassLoader [] fPluginLoaders;
31
32 private ClassLoader fContextClassloader = null;
33
34 public AntClassLoader(URL [] urls, ClassLoader [] pluginLoaders) {
35 super(urls, ClassLoader.getSystemClassLoader());
36 fPluginLoaders = pluginLoaders;
37 }
38
39
42 protected Class findClass(String name) throws ClassNotFoundException {
43 Class result = null;
44 if (fAllowPluginLoading || !(name.startsWith(ANT_PACKAGES_PREFIX))) {
47 result = loadClassPlugins(name);
48 }
49
50 if (result != null) {
51 return result;
52 }
53
54 return super.findClass(name);
55 }
56
57 protected Class loadClassPlugins(String name) {
58 ClassLoader originalClassLoader = Thread.currentThread().getContextClassLoader();
61 if (fContextClassloader != null) {
62 Thread.currentThread().setContextClassLoader(fContextClassloader);
63 }
64 try {
65 Class result = null;
66 if (fPluginLoaders != null) {
67 for (int i = 0; (i < fPluginLoaders.length) && (result == null); i++) {
68 try {
69 result = fPluginLoaders[i].loadClass(name);
70 } catch (ClassNotFoundException e) {
71 }
74 }
75 }
76 return result;
77 } finally {
78 Thread.currentThread().setContextClassLoader(originalClassLoader);
79 }
80 }
81
82
85 public URL findResource(String name) {
86 if (fAllowPluginLoading || !(name.startsWith(ANT_URL_PREFIX))) {
87 URL result = findResourcePlugins(name);
88 if (result != null) {
89 return result;
90 }
91 }
92
93 return super.findResource(name);
94 }
95
96 private URL findResourcePlugins(String name) {
97 ClassLoader originalClassLoader = Thread.currentThread().getContextClassLoader();
100 if (fContextClassloader != null) {
101 Thread.currentThread().setContextClassLoader(fContextClassloader);
102 }
103 try {
104 URL result = null;
105 if (fPluginLoaders != null) {
106 for (int i = 0; i < fPluginLoaders.length; i++) {
107 result = fPluginLoaders[i].getResource(name);
108 if (result != null) {
109 return result;
110 }
111 }
112 }
113 } finally {
114 Thread.currentThread().setContextClassLoader(originalClassLoader);
115 }
116 return null;
117 }
118
119
122 public Enumeration findResources(String name) throws IOException {
123 ClassLoader originalClassLoader = Thread.currentThread().getContextClassLoader();
124 if (fContextClassloader != null) {
125 Thread.currentThread().setContextClassLoader(fContextClassloader);
126 }
127 List all = new ArrayList ();
128 try {
129 if (fAllowPluginLoading || !(name.startsWith(ANT_URL_PREFIX) || name.startsWith(ANT_URL_PREFIX, 1))) {
130 if (fPluginLoaders != null) {
131 Enumeration result = null;
132 for (int i = 0; i < fPluginLoaders.length; i++) {
133 result = fPluginLoaders[i].getResources(name);
134 while (result.hasMoreElements()) {
135 all.add(result.nextElement());
136 }
137 }
138 }
139 }
140
141 Enumeration superResources = super.findResources(name);
142 if (all.isEmpty()) {
143 return superResources;
144 }
145
146 while (superResources.hasMoreElements()) {
147 all.add(superResources.nextElement());
148 }
149 return Collections.enumeration(all);
150 } finally {
151 Thread.currentThread().setContextClassLoader(originalClassLoader);
152 }
153 }
154
155
162 public void allowPluginClassLoadersToLoadAnt(boolean allowLoading) {
163 fAllowPluginLoading = allowLoading;
164 }
165
166 public void setPluginContextClassloader(ClassLoader classLoader) {
167 fContextClassloader = classLoader;
168 }
169 } |
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