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1
25
26 package org.objectweb.easybeans.component.smartclient.client;
27
28 import static org.objectweb.easybeans.component.smartclient.api.ProtocolConstants.PROTOCOL_VERSION;
29
30 import java.io.File  ;
31 import java.io.FileOutputStream ;
32 import java.io.IOException ;
33 import java.net.InetSocketAddress ;
34 import java.net.URL ;
35 import java.net.URLClassLoader ;
36 import java.nio.ByteBuffer ;
37 import java.nio.channels.SocketChannel ;
38 import java.util.logging.Level ;
39 import java.util.logging.Logger ;
40
41 import org.objectweb.easybeans.component.smartclient.api.Message;
42 import org.objectweb.easybeans.component.smartclient.api.ProtocolConstants;
43 import org.objectweb.easybeans.component.smartclient.message.ClassAnswer;
44 import org.objectweb.easybeans.component.smartclient.message.ClassNotFound;
45 import org.objectweb.easybeans.component.smartclient.message.ClassRequest;
46 import org.objectweb.easybeans.component.smartclient.message.ProviderURLAnswer;
47 import org.objectweb.easybeans.component.smartclient.message.ProviderURLRequest;
48 import org.objectweb.easybeans.component.smartclient.message.ResourceAnswer;
49 import org.objectweb.easybeans.component.smartclient.message.ResourceRequest;
50
51
55 public class AskingClassLoader extends URLClassLoader {
56
57
60 private static Logger logger = Logger.getLogger(AskingClassLoader.class.getName());
61
62
65 private static final int DEFAULT_BUFFER_SIZE = 1024;
66
67
70 private InetSocketAddress socketAddress = null;
71
72
75 private static int nbClasses = 0;
76
77
80 private static int nbResources = 0;
81
82
85 private static long nbBytes = 0;
86
87
90 private static long timeToDownload = 0;
91
92
97 public AskingClassLoader(final String host, final int portNumber) {
98 super(new URL [0]);
99
100 socketAddress = new InetSocketAddress (host, portNumber);
102
103 Runtime.getRuntime().addShutdownHook(new ShutdownHook());
105
106 }
107
108
112 private SocketChannel getChannel() {
113 SocketChannel channel = null;
114
115 try {
117 channel = SocketChannel.open();
118 } catch (IOException e) {
119 cleanChannel(channel);
120 throw new IllegalStateException ("Cannot open a channel", e);
121 }
122
123 try {
125 channel.connect(socketAddress);
126 } catch (IOException e) {
127 cleanChannel(channel);
128 throw new IllegalStateException ("Cannot connect the channel", e);
129 }
130
131 return channel;
132 }
133
134
138 private void cleanChannel(final SocketChannel channel) {
139 if (channel != null) {
140 try {
141 channel.close();
142 } catch (IOException e) {
143 logger.log(Level.FINE, "Cannot close the given channel", e);
144 }
145 }
146 }
147
148
154 public ByteBuffer sendRequest(final Message message, final SocketChannel channel) {
155 try {
157 channel.write(message.getMessage());
158 } catch (IOException e) {
159 cleanChannel(channel);
160 throw new IllegalStateException ("Cannot send the given message '" + message + "'.", e);
161 }
162
163 ByteBuffer buffer = ByteBuffer.allocateDirect(DEFAULT_BUFFER_SIZE);
165
166 ByteBuffer completeBuffer = null;
167 try {
168 int length = 0;
169 boolean finished = false;
170 while (!finished && (channel.read(buffer)) != -1) {
171 if (buffer.position() >= Message.HEADER_SIZE) {
173 if (completeBuffer == null) {
175 length = buffer.getInt(2);
176 completeBuffer = ByteBuffer.allocate(Message.HEADER_SIZE + length + DEFAULT_BUFFER_SIZE);
179
180 }
181 }
182 buffer.flip();
184 completeBuffer.put(buffer);
185
186 buffer.clear();
188
189 if (completeBuffer.position() >= Message.HEADER_SIZE + length) {
190 completeBuffer.limit(Message.HEADER_SIZE + length);
191 completeBuffer.position(Message.HEADER_SIZE);
193 finished = true;
194 break;
195 }
196 }
197 } catch (Exception e) {
198 cleanChannel(channel);
199 throw new IllegalStateException ("Cannot read the answer from the server.", e);
200 }
201
202 return completeBuffer;
203
204 }
205
206
215 @Override
216 protected synchronized Class <?> findClass(final String name) throws ClassNotFoundException {
217 Class <?> clazz = null;
219
220 try {
221 super.findClass(name);
222 } catch (ClassNotFoundException cnfe) {
223 SocketChannel channel = null;
224 try {
225 long tStart = System.currentTimeMillis();
226 channel = getChannel();
228 ByteBuffer answerBuffer = sendRequest(new ClassRequest(name), channel);
229
230 byte opCode = getOpCode(answerBuffer, channel);
232
233 timeToDownload = timeToDownload + (System.currentTimeMillis() - tStart);
235
236 switch (opCode) {
238 case ProtocolConstants.CLASS_ANSWER:
239 ClassAnswer classAnswer = new ClassAnswer(answerBuffer);
240 try {
241 clazz = loadClass(name, classAnswer.getByteCode());
242 } catch (IOException e) {
243 throw new ClassNotFoundException ("Cannot find the class", e);
244 }
245 nbClasses++;
246 nbBytes = nbBytes + classAnswer.getByteCode().length;
247 break;
248 case ProtocolConstants.CLASS_NOT_FOUND:
249 ClassNotFound classNotFound = new ClassNotFound(answerBuffer);
250 throw new ClassNotFoundException ("The class '" + classNotFound.getName()
251 + "' was not found on the remote side");
252 default:
253 throw new ClassNotFoundException ("Invalid opCode '" + opCode + "' received");
254 }
255 } finally {
256 cleanChannel(channel);
258 }
259 }
260
261 return clazz;
262
263 }
264
265
269 public String getProviderURL() {
270 String providerURL = null;
271 SocketChannel channel = null;
272 try {
273 long tStart = System.currentTimeMillis();
274 channel = getChannel();
276 ByteBuffer answerBuffer = sendRequest(new ProviderURLRequest(), channel);
277
278 byte opCode = getOpCode(answerBuffer, channel);
280
281 timeToDownload = timeToDownload + (System.currentTimeMillis() - tStart);
283
284 switch (opCode) {
286 case ProtocolConstants.PROVIDER_URL_ANSWER:
287 ProviderURLAnswer providerURLAnswer = new ProviderURLAnswer(answerBuffer);
288 providerURL = providerURLAnswer.getProviderURL();
289 break;
290 default:
291 throw new IllegalStateException ("Invalid opCode '" + opCode + "' received");
292 }
293 } finally {
294 cleanChannel(channel);
296 }
297 return providerURL;
298 }
299
300
306 private byte getOpCode(final ByteBuffer buffer, final SocketChannel channel) {
307 byte version = buffer.get(0);
309 if (version != PROTOCOL_VERSION) {
310 cleanChannel(channel);
311 throw new IllegalStateException ("Invalid protocol version : waiting '" + PROTOCOL_VERSION + "', got '" + version
312 + "'.");
313 }
314
315 byte opCode = buffer.get(1);
317 int length = buffer.getInt(2);
319 if (length < 0) {
320 cleanChannel(channel);
321 throw new IllegalStateException ("Invalid length for client '" + length + "'.");
322 }
323 return opCode;
324 }
325
326
333 @Override
334 public synchronized URL findResource(final String name) {
335 URL url = null;
336 url = super.findResource(name);
337
338 if (url != null) {
339 return url;
340 }
341
342 if (name.startsWith("META-INF")) {
343 return null;
344 }
345
346 SocketChannel channel = null;
347 try {
348 long tStart = System.currentTimeMillis();
349
350 channel = getChannel();
352 ByteBuffer answerBuffer = sendRequest(new ResourceRequest(name), channel);
353
354 byte opCode = getOpCode(answerBuffer, channel);
356
357 timeToDownload = timeToDownload + (System.currentTimeMillis() - tStart);
359
360 switch (opCode) {
362 case ProtocolConstants.RESOURCE_ANSWER:
363 ResourceAnswer resourceAnswer = new ResourceAnswer(answerBuffer);
364 String resourceName = resourceAnswer.getResourceName();
365 byte[] bytes = resourceAnswer.getBytes();
366
367 nbResources++;
368 nbBytes = nbBytes + resourceAnswer.getBytes().length;
369
370 File fConfDir = new File (System.getProperty("java.io.tmpdir") + File.separator + "easybeans-smart");
371 if (!fConfDir.exists()) {
372 fConfDir.mkdir();
373 }
374
375 String [] tokens = resourceName.split("/");
377 StringBuilder sb = new StringBuilder ();
378 for (String token : tokens) {
379 if (sb.length() > 0) {
380 sb.append(File.separator);
381 }
382 sb.append(token);
383 }
384
385 File urlFile = new File (fConfDir, sb.toString());
387 if (!urlFile.getParentFile().exists()) {
388 urlFile.getParentFile().mkdir();
389 }
390
391 FileOutputStream fos = new FileOutputStream (urlFile);
393 fos.write(bytes);
394 fos.close();
395 url = urlFile.toURI().toURL();
396 break;
397 case ProtocolConstants.RESOURCE_NOT_FOUND:
398 url = null;
399 break;
400 default:
401 throw new IllegalStateException ("Invalid opCode '" + opCode + "' received");
402 }
403 } catch (Exception e) {
404 logger.log(Level.SEVERE, "Cannot handle : findResource '" + name + "'", e);
405 } finally {
406 cleanChannel(channel);
408 }
409
410 return url;
411 }
412
413
420
421 private Class loadClass(final String className, final byte[] bytecode) throws IOException {
422 Class clazz = null;
424 try {
425 ClassLoader loader = this;
426 Class cls = Class.forName("java.lang.ClassLoader");
427 java.lang.reflect.Method method = cls.getDeclaredMethod("defineClass", new Class [] {String .class, byte[].class,
428 int.class, int.class });
429
430 method.setAccessible(true);
432 try {
433 Object [] args = new Object [] {className, bytecode, new Integer (0), new Integer (bytecode.length) };
434 clazz = (Class ) method.invoke(loader, args);
435 } finally {
436 method.setAccessible(false);
437 }
438 } catch (Exception e) {
439 IOException ioe = new IOException ("Cannt define class with name '" + className + "'.");
440 ioe.initCause(e);
441 throw ioe;
442 }
443 return clazz;
444 }
445
446
450 static class ShutdownHook extends Thread {
451
452
455 @Override
456 public void run() {
457 System.out.println("Downloaded '" + nbClasses + "' classes, '" + nbResources + "' resources for a total of '"
459 + nbBytes + "' bytes and it took '" + timeToDownload + "' ms.");
460 }
461 }
462 }
463 |
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