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1
18
19 package alt.jiapi.util;
20
21 import java.io.File  ;
22 import java.io.IOException ;
23 import java.net.JarURLConnection ;
24 import java.net.MalformedURLException ;
25 import java.net.URL ;
26 import java.net.URLClassLoader ;
27 import java.security.CodeSource ;
28 import java.security.cert.Certificate ;
29 import java.util.Collections ;
30 import java.util.ArrayList ;
31 import java.util.HashMap ;
32 import java.util.List ;
33 import java.util.Map ;
34 import java.util.StringTokenizer ;
35
36 import org.apache.log4j.Category;
37
38 import alt.jiapi.InstrumentationContext;
39 import alt.jiapi.Runtime;
40 import alt.jiapi.reflect.JiapiClass;
41 import alt.jiapi.JiapiException;
42
43
54 public class InstrumentingClassLoader extends URLClassLoader {
55 private static Category log = Runtime.getLogCategory(InstrumentingClassLoader.class);
56
57 protected Map classes;
58 protected InstrumentationContext ctx;
59
60
63 public static ClassLoader createClassLoader() {
64 return createClassLoader((InstrumentationContext)null);
65 }
66
67
70 public static ClassLoader createClassLoader(InstrumentationContextProvider icp) throws JiapiException {
71 return createClassLoader(icp.getInstrumentationContext());
72 }
73
74
77 public static ClassLoader createClassLoader(InstrumentationContextProvider icp, ClassLoader parent) throws JiapiException {
78 return createClassLoader(icp.getInstrumentationContext(), parent);
79 }
80
81
84 public static ClassLoader createClassLoader(InstrumentationContext ctx) {
85 return createClassLoader(ctx, getSystemClassLoader());
86 }
87
88
91 public static ClassLoader createClassLoader(InstrumentationContext ctx,
92 ClassLoader parent) {
93 URL urls[] = getClassPathUrls();
94 SecurityManager sm = System.getSecurityManager();
95 if (sm != null) {
96 sm.checkCreateClassLoader();
97 }
98
99
101 return new InstrumentingClassLoader(ctx, urls, parent);
102 }
103
104 protected InstrumentingClassLoader(InstrumentationContext ctx, URL [] urls,
105 ClassLoader parent) {
106 super(urls, parent);
107 this.ctx = ctx;
108
109 classes = Collections.synchronizedMap(new HashMap ());
110 }
111
112 protected synchronized Class loadClass(String className, boolean resolve)
113 throws ClassNotFoundException {
114
116 Class cl = null;
117 JiapiClass jiapiClass = null;
118 log.debug("loadClass(" + className + ")");
119
121 if (className.startsWith("java.") || className.startsWith("javax.") ||
124 className.startsWith("sun.") || className.startsWith("alt.jiapi.")) {
125 return getParent().loadClass(className);
128 }
129
130 if ((cl = (Class ) classes.get(className)) == null) {
131 log.debug("cache miss: " + className);
132 SecurityManager sm = System.getSecurityManager();
134 if (sm != null) {
135 int i = className.lastIndexOf('.');
136 if (i != -1) {
137 sm.checkPackageAccess(className.substring(0, i));
138 }
139 }
140
141 if (ctx == null) {
142 return bootstrap(className);
143 }
144
145 String path = className.replace('.', '/').concat(".class");
147 URL location = super.findResource(path);
148
149 if (location == null) {
150
152 return getParent().loadClass(className);
153 }
154
155 try {
156 jiapiClass = ctx.getLoader().loadClass(className, location);
157 }
158 catch(java.io.IOException ioe) {
159 throw new ClassNotFoundException (className);
160 }
161
162 ctx.instrument(jiapiClass);
163
164 byte[] bytes = jiapiClass.getByteCode();
165
166 if (System.getProperty("dump") != null) {
167 try {
168 jiapiClass.dump(new java.io.FileOutputStream (jiapiClass.getName() + ".dump"));
169 }
170 catch(Throwable t) {
171 }
172 }
173
174 if (bytes != null) {
175 CodeSource cs = createCodeSource(location);
176 cl = defineClass(className, bytes, 0, bytes.length, cs);
177 }
178
179 log.debug(cl + " was loaded with " + cl.getClassLoader());
180
181 classes.put(className, cl);
186 }
187
188 if (resolve) {
189 resolveClass(cl);
190 }
191
192 return cl;
193 }
194
195
200 protected CodeSource createCodeSource(URL location) {
201 Certificate []certs = null;
202 if (location.getProtocol().equals("jar")) {
203 try {
204 JarURLConnection jarConnection =
205 (JarURLConnection ) location.openConnection();
206
207 certs = jarConnection.getCertificates();
208 location = jarConnection.getJarFileURL();
209 } catch (IOException ioe) {
210 ioe.printStackTrace();
211 throw new RuntimeException (ioe.getMessage());
212 }
213 }
214
215 return new CodeSource (location, certs);
216 }
217
218
219
222 private static URL []getClassPathUrls() {
223 String string = System.getProperty("java.class.path");
224 List urls = new ArrayList ();
225 if (string != null) {
226 StringTokenizer st = new StringTokenizer (string,
227 File.pathSeparator);
228
229 while (st.hasMoreTokens()) {
230 try {
231 urls.add((new File (st.nextToken())).toURL());
232 } catch (IOException ioe) {
233 }
236 }
237 }
238
239 return ((URL []) urls.toArray(new URL [0]));
240 }
241
242
247 public void setContext(InstrumentationContext ctx) {
248 this.ctx = ctx;
249 }
250
251 public Class bootstrap(String className) throws ClassNotFoundException {
253 String s = className.replace('.', '/') + ".class";
254
255 return findClass(s);
256 }
257
258 byte [] byteBuffer = new byte[65000];
260 public Class findClass(String name) throws ClassNotFoundException {
261 log.debug("findClass(" + name + ")");
262 Class c = null;
263 try {
265 URL url = findResource(name);
266 if (url == null) {
267 throw new ClassNotFoundException (name);
268 }
269
270 java.io.InputStream is = url.openStream();
271 int count = 0;
272 while (is.available() > 0) {
273 int elemsRead = is.read(byteBuffer, count, is.available());
274 if (elemsRead == -1) {
275 break;
276 }
277 count += elemsRead;
278 }
279
280 c = defineClass(name.substring(0, name.lastIndexOf('.')),
281 byteBuffer, 0, count);
282 }
283 catch (java.io.IOException e) {
284 e.printStackTrace();
285 throw new ClassNotFoundException (name);
286 }
287
288 classes.put(c.getName(), c);
289 return c;
290 }
291 }
292
293 |
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