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1   /*
2    *  Licensed to the Apache Software Foundation (ASF) under one
3    *  or more contributor license agreements.  See the NOTICE file
4    *  distributed with this work for additional information
5    *  regarding copyright ownership.  The ASF licenses this file
6    *  to you under the Apache License, Version 2.0 (the
7    *  "License"); you may not use this file except in compliance
8    *  with the License.  You may obtain a copy of the License at
9    *
10   *    http://www.apache.org/licenses/LICENSE-2.0
11   *
12   *  Unless required by applicable law or agreed to in writing,
13   *  software distributed under the License is distributed on an
14   *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15   *  KIND, either express or implied.  See the License for the
16   *  specific language governing permissions and limitations
17   *  under the License.
18   *
19   */
20  package org.apache.mina.core.service;
21  
22  import java.util.AbstractSet;
23  import java.util.Iterator;
24  import java.util.List;
25  import java.util.Map;
26  import java.util.Set;
27  import java.util.concurrent.Executor;
28  import java.util.concurrent.ExecutorService;
29  import java.util.concurrent.Executors;
30  import java.util.concurrent.TimeUnit;
31  import java.util.concurrent.atomic.AtomicInteger;
32  
33  import org.apache.mina.core.IoUtil;
34  import org.apache.mina.core.filterchain.DefaultIoFilterChain;
35  import org.apache.mina.core.filterchain.DefaultIoFilterChainBuilder;
36  import org.apache.mina.core.filterchain.IoFilterChainBuilder;
37  import org.apache.mina.core.future.ConnectFuture;
38  import org.apache.mina.core.future.DefaultIoFuture;
39  import org.apache.mina.core.future.IoFuture;
40  import org.apache.mina.core.future.WriteFuture;
41  import org.apache.mina.core.session.AbstractIoSession;
42  import org.apache.mina.core.session.DefaultIoSessionDataStructureFactory;
43  import org.apache.mina.core.session.IdleStatus;
44  import org.apache.mina.core.session.IoSession;
45  import org.apache.mina.core.session.IoSessionConfig;
46  import org.apache.mina.core.session.IoSessionDataStructureFactory;
47  import org.apache.mina.core.session.IoSessionInitializationException;
48  import org.apache.mina.core.session.IoSessionInitializer;
49  import org.apache.mina.util.ExceptionMonitor;
50  import org.apache.mina.util.NamePreservingRunnable;
51  import org.slf4j.Logger;
52  import org.slf4j.LoggerFactory;
53  
54  /**
55   * Base implementation of {@link IoService}s.
56   * 
57   * An instance of IoService contains an Executor which will handle the incoming
58   * events.
59   *
60   * @author <a href="http://mina.apache.org">Apache MINA Project</a>
61   */
62  public abstract class AbstractIoService implements IoService {
63  
64      private static final Logger LOGGER = LoggerFactory.getLogger(AbstractIoService.class);
65  
66      /**
67       * The unique number identifying the Service. It's incremented
68       * for each new IoService created.
69       */
70      private static final AtomicInteger id = new AtomicInteger();
71  
72      /**
73       * The thread name built from the IoService inherited
74       * instance class name and the IoService Id
75       **/
76      private final String threadName;
77  
78      /**
79       * The associated executor, responsible for handling execution of I/O events.
80       */
81      private final Executor executor;
82  
83      /**
84       * A flag used to indicate that the local executor has been created
85       * inside this instance, and not passed by a caller.
86       * 
87       * If the executor is locally created, then it will be an instance
88       * of the ThreadPoolExecutor class.
89       */
90      private final boolean createdExecutor;
91  
92      /**
93       * The IoHandler in charge of managing all the I/O Events. It is
94       */
95      private IoHandler handler;
96  
97      /**
98       * The default {@link IoSessionConfig} which will be used to configure new sessions.
99       */
100     protected final IoSessionConfig sessionConfig;
101 
102     private final IoServiceListener serviceActivationListener = new IoServiceListener() {
103         public void serviceActivated(IoService service) {
104             // Update lastIoTime.
105             AbstractIoService s = (AbstractIoService) service;
106             IoServiceStatistics _stats = s.getStatistics();
107             _stats.setLastReadTime(s.getActivationTime());
108             _stats.setLastWriteTime(s.getActivationTime());
109             _stats.setLastThroughputCalculationTime(s.getActivationTime());
110 
111         }
112 
113         public void serviceDeactivated(IoService service) throws Exception {
114             // Empty handler
115         }
116 
117         public void serviceIdle(IoService service, IdleStatus idleStatus) throws Exception {
118             // Empty handler
119         }
120 
121         public void sessionCreated(IoSession session) throws Exception {
122             // Empty handler
123         }
124 
125         public void sessionClosed(IoSession session) throws Exception {
126             // Empty handler
127         }
128 
129         public void sessionDestroyed(IoSession session) throws Exception {
130             // Empty handler
131         }
132     };
133 
134     /**
135      * Current filter chain builder.
136      */
137     private IoFilterChainBuilder filterChainBuilder = new DefaultIoFilterChainBuilder();
138 
139     private IoSessionDataStructureFactory sessionDataStructureFactory = new DefaultIoSessionDataStructureFactory();
140 
141     /**
142      * Maintains the {@link IoServiceListener}s of this service.
143      */
144     private final IoServiceListenerSupport listeners;
145 
146     /**
147      * A lock object which must be acquired when related resources are
148      * destroyed.
149      */
150     protected final Object disposalLock = new Object();
151 
152     private volatile boolean disposing;
153 
154     private volatile boolean disposed;
155 
156     /**
157      * {@inheritDoc}
158      */
159     private IoServiceStatistics stats = new IoServiceStatistics(this);
160 
161     /**
162      * Constructor for {@link AbstractIoService}. You need to provide a default
163      * session configuration and an {@link Executor} for handling I/O events. If
164      * a null {@link Executor} is provided, a default one will be created using
165      * {@link Executors#newCachedThreadPool()}.
166      * 
167      * @param sessionConfig
168      *            the default configuration for the managed {@link IoSession}
169      * @param executor
170      *            the {@link Executor} used for handling execution of I/O
171      *            events. Can be <code>null</code>.
172      */
173     protected AbstractIoService(IoSessionConfig sessionConfig, Executor executor) {
174         if (sessionConfig == null) {
175             throw new IllegalArgumentException("sessionConfig");
176         }
177 
178         if (getTransportMetadata() == null) {
179             throw new IllegalArgumentException("TransportMetadata");
180         }
181 
182         if (!getTransportMetadata().getSessionConfigType().isAssignableFrom(sessionConfig.getClass())) {
183             throw new IllegalArgumentException("sessionConfig type: " + sessionConfig.getClass() + " (expected: "
184                     + getTransportMetadata().getSessionConfigType() + ")");
185         }
186 
187         // Create the listeners, and add a first listener : a activation listener
188         // for this service, which will give information on the service state.
189         listeners = new IoServiceListenerSupport(this);
190         listeners.add(serviceActivationListener);
191 
192         // Stores the given session configuration
193         this.sessionConfig = sessionConfig;
194 
195         // Make JVM load the exception monitor before some transports
196         // change the thread context class loader.
197         ExceptionMonitor.getInstance();
198 
199         if (executor == null) {
200             this.executor = Executors.newCachedThreadPool();
201             createdExecutor = true;
202         } else {
203             this.executor = executor;
204             createdExecutor = false;
205         }
206 
207         threadName = getClass().getSimpleName() + '-' + id.incrementAndGet();
208     }
209 
210     /**
211      * {@inheritDoc}
212      */
213     public final IoFilterChainBuilder getFilterChainBuilder() {
214         return filterChainBuilder;
215     }
216 
217     /**
218      * {@inheritDoc}
219      */
220     public final void setFilterChainBuilder(IoFilterChainBuilder builder) {
221         if (builder == null) {
222             builder = new DefaultIoFilterChainBuilder();
223         }
224         filterChainBuilder = builder;
225     }
226 
227     /**
228      * {@inheritDoc}
229      */
230     public final DefaultIoFilterChainBuilder getFilterChain() {
231         if (filterChainBuilder instanceof DefaultIoFilterChainBuilder) {
232             return (DefaultIoFilterChainBuilder) filterChainBuilder;
233         }
234 
235         throw new IllegalStateException("Current filter chain builder is not a DefaultIoFilterChainBuilder.");
236     }
237 
238     /**
239      * {@inheritDoc}
240      */
241     public final void addListener(IoServiceListener listener) {
242         listeners.add(listener);
243     }
244 
245     /**
246      * {@inheritDoc}
247      */
248     public final void removeListener(IoServiceListener listener) {
249         listeners.remove(listener);
250     }
251 
252     /**
253      * {@inheritDoc}
254      */
255     public final boolean isActive() {
256         return listeners.isActive();
257     }
258 
259     /**
260      * {@inheritDoc}
261      */
262     public final boolean isDisposing() {
263         return disposing;
264     }
265 
266     /**
267      * {@inheritDoc}
268      */
269     public final boolean isDisposed() {
270         return disposed;
271     }
272 
273     /**
274      * {@inheritDoc}
275      */
276     public final void dispose() {
277         dispose(false);
278     }
279 
280     /**
281      * {@inheritDoc}
282      */
283     public final void dispose(boolean awaitTermination) {
284         if (disposed) {
285             return;
286         }
287 
288         synchronized (disposalLock) {
289             if (!disposing) {
290                 disposing = true;
291 
292                 try {
293                     dispose0();
294                 } catch (Exception e) {
295                     ExceptionMonitor.getInstance().exceptionCaught(e);
296                 }
297             }
298         }
299 
300         if (createdExecutor) {
301             ExecutorService e = (ExecutorService) executor;
302             e.shutdownNow();
303             if (awaitTermination) {
304 
305                 try {
306                     LOGGER.debug("awaitTermination on {} called by thread=[{}]", this, Thread.currentThread().getName());
307                     e.awaitTermination(Integer.MAX_VALUE, TimeUnit.SECONDS);
308                     LOGGER.debug("awaitTermination on {} finished", this);
309                 } catch (InterruptedException e1) {
310                     LOGGER.warn("awaitTermination on [{}] was interrupted", this);
311                     // Restore the interrupted status
312                     Thread.currentThread().interrupt();
313                 }
314             }
315         }
316         disposed = true;
317     }
318 
319     /**
320      * Implement this method to release any acquired resources.  This method
321      * is invoked only once by {@link #dispose()}.
322      */
323     protected abstract void dispose0() throws Exception;
324 
325     /**
326      * {@inheritDoc}
327      */
328     public final Map<Long, IoSession> getManagedSessions() {
329         return listeners.getManagedSessions();
330     }
331 
332     /**
333      * {@inheritDoc}
334      */
335     public final int getManagedSessionCount() {
336         return listeners.getManagedSessionCount();
337     }
338 
339     /**
340      * {@inheritDoc}
341      */
342     public final IoHandler getHandler() {
343         return handler;
344     }
345 
346     /**
347      * {@inheritDoc}
348      */
349     public final void setHandler(IoHandler handler) {
350         if (handler == null) {
351             throw new IllegalArgumentException("handler cannot be null");
352         }
353 
354         if (isActive()) {
355             throw new IllegalStateException("handler cannot be set while the service is active.");
356         }
357 
358         this.handler = handler;
359     }
360 
361     /**
362      * {@inheritDoc}
363      */
364     public final IoSessionDataStructureFactory getSessionDataStructureFactory() {
365         return sessionDataStructureFactory;
366     }
367 
368     /**
369      * {@inheritDoc}
370      */
371     public final void setSessionDataStructureFactory(IoSessionDataStructureFactory sessionDataStructureFactory) {
372         if (sessionDataStructureFactory == null) {
373             throw new IllegalArgumentException("sessionDataStructureFactory");
374         }
375 
376         if (isActive()) {
377             throw new IllegalStateException("sessionDataStructureFactory cannot be set while the service is active.");
378         }
379 
380         this.sessionDataStructureFactory = sessionDataStructureFactory;
381     }
382 
383     /**
384      * {@inheritDoc}
385      */
386     public IoServiceStatistics getStatistics() {
387         return stats;
388     }
389 
390     /**
391      * {@inheritDoc}
392      */
393     public final long getActivationTime() {
394         return listeners.getActivationTime();
395     }
396 
397     /**
398      * {@inheritDoc}
399      */
400     public final Set<WriteFuture> broadcast(Object message) {
401         // Convert to Set.  We do not return a List here because only the
402         // direct caller of MessageBroadcaster knows the order of write
403         // operations.
404         final List<WriteFuture> futures = IoUtil.broadcast(message, getManagedSessions().values());
405         return new AbstractSet<WriteFuture>() {
406             @Override
407             public Iterator<WriteFuture> iterator() {
408                 return futures.iterator();
409             }
410 
411             @Override
412             public int size() {
413                 return futures.size();
414             }
415         };
416     }
417 
418     public final IoServiceListenerSupport getListeners() {
419         return listeners;
420     }
421 
422     protected final void executeWorker(Runnable worker) {
423         executeWorker(worker, null);
424     }
425 
426     protected final void executeWorker(Runnable worker, String suffix) {
427         String actualThreadName = threadName;
428         if (suffix != null) {
429             actualThreadName = actualThreadName + '-' + suffix;
430         }
431         executor.execute(new NamePreservingRunnable(worker, actualThreadName));
432     }
433 
434     // TODO Figure out make it work without causing a compiler error / warning.
435     @SuppressWarnings("unchecked")
436     protected final void initSession(IoSession session, IoFuture future, IoSessionInitializer sessionInitializer) {
437         // Update lastIoTime if needed.
438         if (stats.getLastReadTime() == 0) {
439             stats.setLastReadTime(getActivationTime());
440         }
441 
442         if (stats.getLastWriteTime() == 0) {
443             stats.setLastWriteTime(getActivationTime());
444         }
445 
446         // Every property but attributeMap should be set now.
447         // Now initialize the attributeMap.  The reason why we initialize
448         // the attributeMap at last is to make sure all session properties
449         // such as remoteAddress are provided to IoSessionDataStructureFactory.
450         try {
451             ((AbstractIoSession) session).setAttributeMap(session.getService().getSessionDataStructureFactory()
452                     .getAttributeMap(session));
453         } catch (IoSessionInitializationException e) {
454             throw e;
455         } catch (Exception e) {
456             throw new IoSessionInitializationException("Failed to initialize an attributeMap.", e);
457         }
458 
459         try {
460             ((AbstractIoSession) session).setWriteRequestQueue(session.getService().getSessionDataStructureFactory()
461                     .getWriteRequestQueue(session));
462         } catch (IoSessionInitializationException e) {
463             throw e;
464         } catch (Exception e) {
465             throw new IoSessionInitializationException("Failed to initialize a writeRequestQueue.", e);
466         }
467 
468         if ((future != null) && (future instanceof ConnectFuture)) {
469             // DefaultIoFilterChain will notify the future. (We support ConnectFuture only for now).
470             session.setAttribute(DefaultIoFilterChain.SESSION_CREATED_FUTURE, future);
471         }
472 
473         if (sessionInitializer != null) {
474             sessionInitializer.initializeSession(session, future);
475         }
476 
477         finishSessionInitialization0(session, future);
478     }
479 
480     /**
481      * Implement this method to perform additional tasks required for session
482      * initialization. Do not call this method directly;
483      * {@link #initSession(IoSession, IoFuture, IoSessionInitializer)} will call
484      * this method instead.
485      */
486     protected void finishSessionInitialization0(IoSession session, IoFuture future) {
487         // Do nothing. Extended class might add some specific code
488     }
489 
490     /**
491      * A specific class used to 
492      * @author elecharny
493      *
494      */
495     protected static class ServiceOperationFuture extends DefaultIoFuture {
496         public ServiceOperationFuture() {
497             super(null);
498         }
499 
500         public final boolean isDone() {
501             return getValue() == Boolean.TRUE;
502         }
503 
504         public final void setDone() {
505             setValue(Boolean.TRUE);
506         }
507 
508         public final Exception getException() {
509             if (getValue() instanceof Exception) {
510                 return (Exception) getValue();
511             }
512 
513             return null;
514         }
515 
516         public final void setException(Exception exception) {
517             if (exception == null) {
518                 throw new IllegalArgumentException("exception");
519             }
520             
521             setValue(exception);
522         }
523     }
524 
525     /**
526      * {@inheritDoc}
527      */
528     public int getScheduledWriteBytes() {
529         return stats.getScheduledWriteBytes();
530     }
531 
532     /**
533      * {@inheritDoc}
534      */
535     public int getScheduledWriteMessages() {
536         return stats.getScheduledWriteMessages();
537     }
538 
539 }