Source Code Cross Referenced for JIoEndpoint.java in  » Sevlet-Container » apache-tomcat-6.0.14 » org » apache » tomcat » util » net » Java Source Code / Java DocumentationJava Source Code and Java Documentation

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Java Source Code / Java Documentation » Sevlet Container » apache tomcat 6.0.14 » org.apache.tomcat.util.net 
Source Cross Referenced  Class Diagram Java Document (Java Doc) 


001:        /*
002:         *  Licensed to the Apache Software Foundation (ASF) under one or more
003:         *  contributor license agreements.  See the NOTICE file distributed with
004:         *  this work for additional information regarding copyright ownership.
005:         *  The ASF licenses this file to You under the Apache License, Version 2.0
006:         *  (the "License"); you may not use this file except in compliance with
007:         *  the License.  You may obtain a copy of the License at
008:         *
009:         *      http://www.apache.org/licenses/LICENSE-2.0
010:         *
011:         *  Unless required by applicable law or agreed to in writing, software
012:         *  distributed under the License is distributed on an "AS IS" BASIS,
013:         *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014:         *  See the License for the specific language governing permissions and
015:         *  limitations under the License.
016:         */
017:
018:        package org.apache.tomcat.util.net;
019:
020:        import java.io.IOException;
021:        import java.net.BindException;
022:        import java.net.InetAddress;
023:        import java.net.ServerSocket;
024:        import java.net.Socket;
025:        import java.util.concurrent.Executor;
026:
027:        import org.apache.juli.logging.Log;
028:        import org.apache.juli.logging.LogFactory;
029:        import org.apache.tomcat.util.res.StringManager;
030:
031:        /**
032:         * Handle incoming TCP connections.
033:         *
034:         * This class implement a simple server model: one listener thread accepts on a socket and
035:         * creates a new worker thread for each incoming connection.
036:         *
037:         * More advanced Endpoints will reuse the threads, use queues, etc.
038:         *
039:         * @author James Duncan Davidson
040:         * @author Jason Hunter
041:         * @author James Todd
042:         * @author Costin Manolache
043:         * @author Gal Shachor
044:         * @author Yoav Shapira
045:         * @author Remy Maucherat
046:         */
047:        public class JIoEndpoint {
048:
049:            // -------------------------------------------------------------- Constants
050:
051:            protected static Log log = LogFactory.getLog(JIoEndpoint.class);
052:
053:            protected StringManager sm = StringManager
054:                    .getManager("org.apache.tomcat.util.net.res");
055:
056:            /**
057:             * The Request attribute key for the cipher suite.
058:             */
059:            public static final String CIPHER_SUITE_KEY = "javax.servlet.request.cipher_suite";
060:
061:            /**
062:             * The Request attribute key for the key size.
063:             */
064:            public static final String KEY_SIZE_KEY = "javax.servlet.request.key_size";
065:
066:            /**
067:             * The Request attribute key for the client certificate chain.
068:             */
069:            public static final String CERTIFICATE_KEY = "javax.servlet.request.X509Certificate";
070:
071:            /**
072:             * The Request attribute key for the session id.
073:             * This one is a Tomcat extension to the Servlet spec.
074:             */
075:            public static final String SESSION_ID_KEY = "javax.servlet.request.ssl_session";
076:
077:            // ----------------------------------------------------------------- Fields
078:
079:            /**
080:             * Available workers.
081:             */
082:            protected WorkerStack workers = null;
083:
084:            /**
085:             * Running state of the endpoint.
086:             */
087:            protected volatile boolean running = false;
088:
089:            /**
090:             * Will be set to true whenever the endpoint is paused.
091:             */
092:            protected volatile boolean paused = false;
093:
094:            /**
095:             * Track the initialization state of the endpoint.
096:             */
097:            protected boolean initialized = false;
098:
099:            /**
100:             * Current worker threads busy count.
101:             */
102:            protected int curThreadsBusy = 0;
103:
104:            /**
105:             * Current worker threads count.
106:             */
107:            protected int curThreads = 0;
108:
109:            /**
110:             * Sequence number used to generate thread names.
111:             */
112:            protected int sequence = 0;
113:
114:            /**
115:             * Associated server socket.
116:             */
117:            protected ServerSocket serverSocket = null;
118:
119:            // ------------------------------------------------------------- Properties
120:
121:            /**
122:             * Acceptor thread count.
123:             */
124:            protected int acceptorThreadCount = 0;
125:
126:            public void setAcceptorThreadCount(int acceptorThreadCount) {
127:                this .acceptorThreadCount = acceptorThreadCount;
128:            }
129:
130:            public int getAcceptorThreadCount() {
131:                return acceptorThreadCount;
132:            }
133:
134:            /**
135:             * External Executor based thread pool.
136:             */
137:            protected Executor executor = null;
138:
139:            public void setExecutor(Executor executor) {
140:                this .executor = executor;
141:            }
142:
143:            public Executor getExecutor() {
144:                return executor;
145:            }
146:
147:            /**
148:             * Maximum amount of worker threads.
149:             */
150:            protected int maxThreads = 40;
151:
152:            public void setMaxThreads(int maxThreads) {
153:                this .maxThreads = maxThreads;
154:            }
155:
156:            public int getMaxThreads() {
157:                return maxThreads;
158:            }
159:
160:            /**
161:             * Priority of the acceptor and poller threads.
162:             */
163:            protected int threadPriority = Thread.NORM_PRIORITY;
164:
165:            public void setThreadPriority(int threadPriority) {
166:                this .threadPriority = threadPriority;
167:            }
168:
169:            public int getThreadPriority() {
170:                return threadPriority;
171:            }
172:
173:            /**
174:             * Server socket port.
175:             */
176:            protected int port;
177:
178:            public int getPort() {
179:                return port;
180:            }
181:
182:            public void setPort(int port) {
183:                this .port = port;
184:            }
185:
186:            /**
187:             * Address for the server socket.
188:             */
189:            protected InetAddress address;
190:
191:            public InetAddress getAddress() {
192:                return address;
193:            }
194:
195:            public void setAddress(InetAddress address) {
196:                this .address = address;
197:            }
198:
199:            /**
200:             * Handling of accepted sockets.
201:             */
202:            protected Handler handler = null;
203:
204:            public void setHandler(Handler handler) {
205:                this .handler = handler;
206:            }
207:
208:            public Handler getHandler() {
209:                return handler;
210:            }
211:
212:            /**
213:             * Allows the server developer to specify the backlog that
214:             * should be used for server sockets. By default, this value
215:             * is 100.
216:             */
217:            protected int backlog = 100;
218:
219:            public void setBacklog(int backlog) {
220:                if (backlog > 0)
221:                    this .backlog = backlog;
222:            }
223:
224:            public int getBacklog() {
225:                return backlog;
226:            }
227:
228:            /**
229:             * Socket TCP no delay.
230:             */
231:            protected boolean tcpNoDelay = false;
232:
233:            public boolean getTcpNoDelay() {
234:                return tcpNoDelay;
235:            }
236:
237:            public void setTcpNoDelay(boolean tcpNoDelay) {
238:                this .tcpNoDelay = tcpNoDelay;
239:            }
240:
241:            /**
242:             * Socket linger.
243:             */
244:            protected int soLinger = 100;
245:
246:            public int getSoLinger() {
247:                return soLinger;
248:            }
249:
250:            public void setSoLinger(int soLinger) {
251:                this .soLinger = soLinger;
252:            }
253:
254:            /**
255:             * Socket timeout.
256:             */
257:            protected int soTimeout = -1;
258:
259:            public int getSoTimeout() {
260:                return soTimeout;
261:            }
262:
263:            public void setSoTimeout(int soTimeout) {
264:                this .soTimeout = soTimeout;
265:            }
266:
267:            /**
268:             * The default is true - the created threads will be
269:             *  in daemon mode. If set to false, the control thread
270:             *  will not be daemon - and will keep the process alive.
271:             */
272:            protected boolean daemon = true;
273:
274:            public void setDaemon(boolean b) {
275:                daemon = b;
276:            }
277:
278:            public boolean getDaemon() {
279:                return daemon;
280:            }
281:
282:            /**
283:             * Name of the thread pool, which will be used for naming child threads.
284:             */
285:            protected String name = "TP";
286:
287:            public void setName(String name) {
288:                this .name = name;
289:            }
290:
291:            public String getName() {
292:                return name;
293:            }
294:
295:            /**
296:             * Server socket factory.
297:             */
298:            protected ServerSocketFactory serverSocketFactory = null;
299:
300:            public void setServerSocketFactory(ServerSocketFactory factory) {
301:                this .serverSocketFactory = factory;
302:            }
303:
304:            public ServerSocketFactory getServerSocketFactory() {
305:                return serverSocketFactory;
306:            }
307:
308:            public boolean isRunning() {
309:                return running;
310:            }
311:
312:            public boolean isPaused() {
313:                return paused;
314:            }
315:
316:            public int getCurrentThreadCount() {
317:                return curThreads;
318:            }
319:
320:            public int getCurrentThreadsBusy() {
321:                return workers != null ? curThreads - workers.size() : 0;
322:            }
323:
324:            // ------------------------------------------------ Handler Inner Interface
325:
326:            /**
327:             * Bare bones interface used for socket processing. Per thread data is to be
328:             * stored in the ThreadWithAttributes extra folders, or alternately in
329:             * thread local fields.
330:             */
331:            public interface Handler {
332:                public boolean process(Socket socket);
333:            }
334:
335:            // --------------------------------------------------- Acceptor Inner Class
336:
337:            /**
338:             * Server socket acceptor thread.
339:             */
340:            protected class Acceptor implements  Runnable {
341:
342:                /**
343:                 * The background thread that listens for incoming TCP/IP connections and
344:                 * hands them off to an appropriate processor.
345:                 */
346:                public void run() {
347:
348:                    // Loop until we receive a shutdown command
349:                    while (running) {
350:
351:                        // Loop if endpoint is paused
352:                        while (paused) {
353:                            try {
354:                                Thread.sleep(1000);
355:                            } catch (InterruptedException e) {
356:                                // Ignore
357:                            }
358:                        }
359:
360:                        // Accept the next incoming connection from the server socket
361:                        try {
362:                            Socket socket = serverSocketFactory
363:                                    .acceptSocket(serverSocket);
364:                            serverSocketFactory.initSocket(socket);
365:                            // Hand this socket off to an appropriate processor
366:                            if (!processSocket(socket)) {
367:                                // Close socket right away
368:                                try {
369:                                    socket.close();
370:                                } catch (IOException e) {
371:                                    // Ignore
372:                                }
373:                            }
374:                        } catch (IOException x) {
375:                            if (running)
376:                                log.error(sm.getString("endpoint.accept.fail"),
377:                                        x);
378:                        } catch (Throwable t) {
379:                            log.error(sm.getString("endpoint.accept.fail"), t);
380:                        }
381:
382:                        // The processor will recycle itself when it finishes
383:
384:                    }
385:
386:                }
387:
388:            }
389:
390:            // ------------------------------------------- SocketProcessor Inner Class
391:
392:            /**
393:             * This class is the equivalent of the Worker, but will simply use in an
394:             * external Executor thread pool.
395:             */
396:            protected class SocketProcessor implements  Runnable {
397:
398:                protected Socket socket = null;
399:
400:                public SocketProcessor(Socket socket) {
401:                    this .socket = socket;
402:                }
403:
404:                public void run() {
405:
406:                    // Process the request from this socket
407:                    if (!setSocketOptions(socket) || !handler.process(socket)) {
408:                        // Close socket
409:                        try {
410:                            socket.close();
411:                        } catch (IOException e) {
412:                        }
413:                    }
414:
415:                    // Finish up this request
416:                    socket = null;
417:
418:                }
419:
420:            }
421:
422:            // ----------------------------------------------------- Worker Inner Class
423:
424:            protected class Worker implements  Runnable {
425:
426:                protected Thread thread = null;
427:                protected boolean available = false;
428:                protected Socket socket = null;
429:
430:                /**
431:                 * Process an incoming TCP/IP connection on the specified socket.  Any
432:                 * exception that occurs during processing must be logged and swallowed.
433:                 * <b>NOTE</b>:  This method is called from our Connector's thread.  We
434:                 * must assign it to our own thread so that multiple simultaneous
435:                 * requests can be handled.
436:                 *
437:                 * @param socket TCP socket to process
438:                 */
439:                synchronized void assign(Socket socket) {
440:
441:                    // Wait for the Processor to get the previous Socket
442:                    while (available) {
443:                        try {
444:                            wait();
445:                        } catch (InterruptedException e) {
446:                        }
447:                    }
448:
449:                    // Store the newly available Socket and notify our thread
450:                    this .socket = socket;
451:                    available = true;
452:                    notifyAll();
453:
454:                }
455:
456:                /**
457:                 * Await a newly assigned Socket from our Connector, or <code>null</code>
458:                 * if we are supposed to shut down.
459:                 */
460:                private synchronized Socket await() {
461:
462:                    // Wait for the Connector to provide a new Socket
463:                    while (!available) {
464:                        try {
465:                            wait();
466:                        } catch (InterruptedException e) {
467:                        }
468:                    }
469:
470:                    // Notify the Connector that we have received this Socket
471:                    Socket socket = this .socket;
472:                    available = false;
473:                    notifyAll();
474:
475:                    return (socket);
476:
477:                }
478:
479:                /**
480:                 * The background thread that listens for incoming TCP/IP connections and
481:                 * hands them off to an appropriate processor.
482:                 */
483:                public void run() {
484:
485:                    // Process requests until we receive a shutdown signal
486:                    while (running) {
487:
488:                        // Wait for the next socket to be assigned
489:                        Socket socket = await();
490:                        if (socket == null)
491:                            continue;
492:
493:                        // Process the request from this socket
494:                        if (!setSocketOptions(socket)
495:                                || !handler.process(socket)) {
496:                            // Close socket
497:                            try {
498:                                socket.close();
499:                            } catch (IOException e) {
500:                            }
501:                        }
502:
503:                        // Finish up this request
504:                        socket = null;
505:                        recycleWorkerThread(this );
506:
507:                    }
508:
509:                }
510:
511:                /**
512:                 * Start the background processing thread.
513:                 */
514:                public void start() {
515:                    thread = new Thread(this );
516:                    thread.setName(getName() + "-" + (++curThreads));
517:                    thread.setDaemon(true);
518:                    thread.start();
519:                }
520:
521:            }
522:
523:            // -------------------- Public methods --------------------
524:
525:            public void init() throws Exception {
526:
527:                if (initialized)
528:                    return;
529:
530:                // Initialize thread count defaults for acceptor
531:                if (acceptorThreadCount == 0) {
532:                    acceptorThreadCount = 1;
533:                }
534:                if (serverSocketFactory == null) {
535:                    serverSocketFactory = ServerSocketFactory.getDefault();
536:                }
537:                if (serverSocket == null) {
538:                    try {
539:                        if (address == null) {
540:                            serverSocket = serverSocketFactory.createSocket(
541:                                    port, backlog);
542:                        } else {
543:                            serverSocket = serverSocketFactory.createSocket(
544:                                    port, backlog, address);
545:                        }
546:                    } catch (BindException be) {
547:                        throw new BindException(be.getMessage() + ":" + port);
548:                    }
549:                }
550:                //if( serverTimeout >= 0 )
551:                //    serverSocket.setSoTimeout( serverTimeout );
552:
553:                initialized = true;
554:
555:            }
556:
557:            public void start() throws Exception {
558:                // Initialize socket if not done before
559:                if (!initialized) {
560:                    init();
561:                }
562:                if (!running) {
563:                    running = true;
564:                    paused = false;
565:
566:                    // Create worker collection
567:                    if (executor == null) {
568:                        workers = new WorkerStack(maxThreads);
569:                    }
570:
571:                    // Start acceptor threads
572:                    for (int i = 0; i < acceptorThreadCount; i++) {
573:                        Thread acceptorThread = new Thread(new Acceptor(),
574:                                getName() + "-Acceptor-" + i);
575:                        acceptorThread.setPriority(threadPriority);
576:                        acceptorThread.setDaemon(daemon);
577:                        acceptorThread.start();
578:                    }
579:                }
580:            }
581:
582:            public void pause() {
583:                if (running && !paused) {
584:                    paused = true;
585:                    unlockAccept();
586:                }
587:            }
588:
589:            public void resume() {
590:                if (running) {
591:                    paused = false;
592:                }
593:            }
594:
595:            public void stop() {
596:                if (running) {
597:                    running = false;
598:                    unlockAccept();
599:                }
600:            }
601:
602:            /**
603:             * Deallocate APR memory pools, and close server socket.
604:             */
605:            public void destroy() throws Exception {
606:                if (running) {
607:                    stop();
608:                }
609:                if (serverSocket != null) {
610:                    try {
611:                        if (serverSocket != null)
612:                            serverSocket.close();
613:                    } catch (Exception e) {
614:                        log.error(sm.getString("endpoint.err.close"), e);
615:                    }
616:                    serverSocket = null;
617:                }
618:                initialized = false;
619:            }
620:
621:            /**
622:             * Unlock the accept by using a local connection.
623:             */
624:            protected void unlockAccept() {
625:                Socket s = null;
626:                try {
627:                    // Need to create a connection to unlock the accept();
628:                    if (address == null) {
629:                        s = new Socket("127.0.0.1", port);
630:                    } else {
631:                        s = new Socket(address, port);
632:                        // setting soLinger to a small value will help shutdown the
633:                        // connection quicker
634:                        s.setSoLinger(true, 0);
635:                    }
636:                } catch (Exception e) {
637:                    if (log.isDebugEnabled()) {
638:                        log.debug(sm.getString("endpoint.debug.unlock", ""
639:                                + port), e);
640:                    }
641:                } finally {
642:                    if (s != null) {
643:                        try {
644:                            s.close();
645:                        } catch (Exception e) {
646:                            // Ignore
647:                        }
648:                    }
649:                }
650:            }
651:
652:            /**
653:             * Set the options for the current socket.
654:             */
655:            protected boolean setSocketOptions(Socket socket) {
656:                // Process the connection
657:                int step = 1;
658:                try {
659:
660:                    // 1: Set socket options: timeout, linger, etc
661:                    if (soLinger >= 0) {
662:                        socket.setSoLinger(true, soLinger);
663:                    }
664:                    if (tcpNoDelay) {
665:                        socket.setTcpNoDelay(tcpNoDelay);
666:                    }
667:                    if (soTimeout > 0) {
668:                        socket.setSoTimeout(soTimeout);
669:                    }
670:
671:                    // 2: SSL handshake
672:                    step = 2;
673:                    serverSocketFactory.handshake(socket);
674:
675:                } catch (Throwable t) {
676:                    if (log.isDebugEnabled()) {
677:                        if (step == 2) {
678:                            log
679:                                    .debug(
680:                                            sm
681:                                                    .getString("endpoint.err.handshake"),
682:                                            t);
683:                        } else {
684:                            log.debug(sm.getString("endpoint.err.unexpected"),
685:                                    t);
686:                        }
687:                    }
688:                    // Tell to close the socket
689:                    return false;
690:                }
691:                return true;
692:            }
693:
694:            /**
695:             * Create (or allocate) and return an available processor for use in
696:             * processing a specific HTTP request, if possible.  If the maximum
697:             * allowed processors have already been created and are in use, return
698:             * <code>null</code> instead.
699:             */
700:            protected Worker createWorkerThread() {
701:
702:                synchronized (workers) {
703:                    if (workers.size() > 0) {
704:                        curThreadsBusy++;
705:                        return workers.pop();
706:                    }
707:                    if ((maxThreads > 0) && (curThreads < maxThreads)) {
708:                        curThreadsBusy++;
709:                        return (newWorkerThread());
710:                    } else {
711:                        if (maxThreads < 0) {
712:                            curThreadsBusy++;
713:                            return (newWorkerThread());
714:                        } else {
715:                            return (null);
716:                        }
717:                    }
718:                }
719:
720:            }
721:
722:            /**
723:             * Create and return a new processor suitable for processing HTTP
724:             * requests and returning the corresponding responses.
725:             */
726:            protected Worker newWorkerThread() {
727:
728:                Worker workerThread = new Worker();
729:                workerThread.start();
730:                return (workerThread);
731:
732:            }
733:
734:            /**
735:             * Return a new worker thread, and block while to worker is available.
736:             */
737:            protected Worker getWorkerThread() {
738:                // Allocate a new worker thread
739:                Worker workerThread = createWorkerThread();
740:                while (workerThread == null) {
741:                    try {
742:                        synchronized (workers) {
743:                            workers.wait();
744:                        }
745:                    } catch (InterruptedException e) {
746:                        // Ignore
747:                    }
748:                    workerThread = createWorkerThread();
749:                }
750:                return workerThread;
751:            }
752:
753:            /**
754:             * Recycle the specified Processor so that it can be used again.
755:             *
756:             * @param workerThread The processor to be recycled
757:             */
758:            protected void recycleWorkerThread(Worker workerThread) {
759:                synchronized (workers) {
760:                    workers.push(workerThread);
761:                    curThreadsBusy--;
762:                    workers.notify();
763:                }
764:            }
765:
766:            /**
767:             * Process given socket.
768:             */
769:            protected boolean processSocket(Socket socket) {
770:                try {
771:                    if (executor == null) {
772:                        getWorkerThread().assign(socket);
773:                    } else {
774:                        executor.execute(new SocketProcessor(socket));
775:                    }
776:                } catch (Throwable t) {
777:                    // This means we got an OOM or similar creating a thread, or that
778:                    // the pool and its queue are full
779:                    log.error(sm.getString("endpoint.process.fail"), t);
780:                    return false;
781:                }
782:                return true;
783:            }
784:
785:            // ------------------------------------------------- WorkerStack Inner Class
786:
787:            public class WorkerStack {
788:
789:                protected Worker[] workers = null;
790:                protected int end = 0;
791:
792:                public WorkerStack(int size) {
793:                    workers = new Worker[size];
794:                }
795:
796:                /** 
797:                 * Put the object into the queue.
798:                 * 
799:                 * @param   object      the object to be appended to the queue (first element). 
800:                 */
801:                public void push(Worker worker) {
802:                    workers[end++] = worker;
803:                }
804:
805:                /**
806:                 * Get the first object out of the queue. Return null if the queue
807:                 * is empty. 
808:                 */
809:                public Worker pop() {
810:                    if (end > 0) {
811:                        return workers[--end];
812:                    }
813:                    return null;
814:                }
815:
816:                /**
817:                 * Get the first object out of the queue, Return null if the queue
818:                 * is empty.
819:                 */
820:                public Worker peek() {
821:                    return workers[end];
822:                }
823:
824:                /**
825:                 * Is the queue empty?
826:                 */
827:                public boolean isEmpty() {
828:                    return (end == 0);
829:                }
830:
831:                /**
832:                 * How many elements are there in this queue?
833:                 */
834:                public int size() {
835:                    return (end);
836:                }
837:            }
838:
839:        }
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