|
1
16 package org.apache.cocoon.portal.event.impl;
17
18 import java.lang.reflect.Method  ;
19 import java.util.ArrayList ;
20 import java.util.HashMap ;
21 import java.util.Iterator ;
22 import java.util.List ;
23 import java.util.Map ;
24
25 import org.apache.avalon.framework.activity.Disposable;
26 import org.apache.avalon.framework.activity.Initializable;
27 import org.apache.avalon.framework.configuration.Configurable;
28 import org.apache.avalon.framework.configuration.Configuration;
29 import org.apache.avalon.framework.configuration.ConfigurationException;
30 import org.apache.avalon.framework.container.ContainerUtil;
31 import org.apache.avalon.framework.context.Context;
32 import org.apache.avalon.framework.context.ContextException;
33 import org.apache.avalon.framework.context.Contextualizable;
34 import org.apache.avalon.framework.logger.AbstractLogEnabled;
35 import org.apache.avalon.framework.service.ServiceException;
36 import org.apache.avalon.framework.service.ServiceManager;
37 import org.apache.avalon.framework.service.ServiceSelector;
38 import org.apache.avalon.framework.service.Serviceable;
39 import org.apache.avalon.framework.thread.ThreadSafe;
40 import org.apache.cocoon.ProcessingException;
41 import org.apache.cocoon.components.ContextHelper;
42 import org.apache.cocoon.portal.PortalService;
43 import org.apache.cocoon.portal.event.Event;
44 import org.apache.cocoon.portal.event.EventConverter;
45 import org.apache.cocoon.portal.event.EventManager;
46 import org.apache.cocoon.portal.event.Publisher;
47 import org.apache.cocoon.portal.event.Receiver;
48 import org.apache.cocoon.portal.event.Register;
49 import org.apache.cocoon.portal.event.Subscriber;
50 import org.apache.cocoon.portal.event.aspect.EventAspect;
51 import org.apache.cocoon.util.ClassUtils;
52 import org.apache.cocoon.util.Deprecation;
53
54
62 public class DefaultEventManager
63 extends AbstractLogEnabled
64 implements EventManager,
65 Serviceable,
66 Initializable,
67 ThreadSafe,
68 Configurable,
69 Disposable,
70 Contextualizable,
71 Publisher, Register {
72
73 private final String rootEventType = Event.class.getName();
74 private Class eventClass;
75
76 private List subscribers = new ArrayList ();
77
78 private Map receivers = new HashMap ();
79
80 private ServiceManager manager;
81 private Configuration configuration;
82
83 protected EventAspectChain chain;
84
85 protected ServiceSelector aspectSelector;
86
87 protected Context context;
88
89
90 protected PortalService service;
91
92
93 protected Map receiverClasses = new HashMap ();
94
95
98 public void service(ServiceManager manager) throws ServiceException {
99 this.manager = manager;
100 this.service = (PortalService)manager.lookup(PortalService.ROLE);
101 }
102
103
106 public Publisher getPublisher() {
107 return this;
108 }
109
110
113 public Register getRegister() {
114 return this;
115 }
116
117
120 protected Map getObjectModel() {
121 return ContextHelper.getObjectModel( this.context );
122 }
123
124
127 public void configure(Configuration conf)
128 throws ConfigurationException {
129 this.configuration = conf;
130 }
131
132
135 public void dispose() {
136 if (this.manager != null) {
137 if ( this.chain != null) {
138 this.chain.dispose( this.aspectSelector );
139 }
140 this.manager.release( this.aspectSelector );
141 this.aspectSelector = null;
142 this.manager.release(this.service);
143 this.service = null;
144 this.manager = null;
145 }
146 }
147
148
151 public void initialize()
152 throws Exception {
153 this.eventClass = Class.forName( rootEventType );
154 if ( this.getLogger().isDebugEnabled() ) {
155 this.getLogger().debug("Initialising eventClass " + eventClass);
156 }
157
158 Configuration roles = this.configuration.getChild("subscriber-roles", false);
161 if ( roles != null ) {
162 Configuration[] rolesConf = roles.getChildren("role");
163 for(int i=0; i<rolesConf.length;i++) {
164 final Configuration current = rolesConf[i];
165 final String name = current.getAttribute("name");
166
167 Subscriber subscriber = null;
168 try {
169 subscriber = (Subscriber) this.manager.lookup(name);
170 Deprecation.logger.warn("Subscriber is deprecated. Please convert the following component to a Receiver: " + subscriber.getClass().getName());
171 this.subscribe(subscriber);
172 } finally {
173 this.manager.release(subscriber);
174 }
175 }
176 }
177 Configuration classes = this.configuration.getChild("subscriber-classes", false);
179 if ( classes != null ) {
180 Configuration[] classesConf = classes.getChildren("class");
181 for(int i=0; i<classesConf.length;i++) {
182 final Configuration current = classesConf[i];
183 final String name = current.getAttribute("name");
184
185 Deprecation.logger.warn("Subscriber is deprecated. Please convert the following component to a Receiver: " + name);
186 Subscriber subscriber = (Subscriber) ClassUtils.newInstance(name);
187 ContainerUtil.enableLogging(subscriber, this.getLogger());
188 ContainerUtil.contextualize(subscriber, this.context);
189 ContainerUtil.service(subscriber, this.manager );
190 ContainerUtil.initialize(subscriber);
191 this.subscribe(subscriber);
192 }
193 }
194 roles = this.configuration.getChild("receiver-roles", false);
196 if ( roles != null ) {
197 Configuration[] rolesConf = roles.getChildren("role");
198 for(int i=0; i<rolesConf.length;i++) {
199 final Configuration current = rolesConf[i];
200 final String name = current.getAttribute("name");
201
202 Receiver receiver = null;
203 try {
204 receiver = (Receiver) this.manager.lookup(name);
205 this.subscribe(receiver);
206 } finally {
207 this.manager.release(receiver);
208 }
209 }
210 }
211 classes = this.configuration.getChild("receiver-classes", false);
213 if ( classes != null ) {
214 Configuration[] classesConf = classes.getChildren("class");
215 for(int i=0; i<classesConf.length;i++) {
216 final Configuration current = classesConf[i];
217 final String name = current.getAttribute("name");
218
219 Receiver receiver = (Receiver)ClassUtils.newInstance(name);
220 ContainerUtil.enableLogging(receiver, this.getLogger());
221 ContainerUtil.contextualize(receiver, this.context);
222 ContainerUtil.service(receiver, this.manager );
223 ContainerUtil.initialize(receiver);
224 this.subscribe(receiver);
225 }
226 }
227
228 }
229
230
233 public void publish( final Event event ) {
234 this.send(event);
235 }
236
237
240 public void subscribe( final Subscriber subscriber ) {
241 if ( !eventClass.isAssignableFrom( subscriber.getEventType() ) ) {
242 throw new RuntimeException ("Invalid event type " + subscriber.getEventType()
243 +" for subscriber " + subscriber);
244 }
245
246 if ( getLogger().isDebugEnabled() ) {
247 getLogger().debug( "Subscribing event " + subscriber.getEventType().getName() );
248 }
249
250 if ( !subscribers.contains( subscriber ) ) {
252 subscribers.add( subscriber );
253 if ( getLogger().isDebugEnabled() ) {
254 getLogger().debug( "Subscribed Event " + subscriber.getEventType().getName() );
255 getLogger().debug( "Subscribers now active: " + subscribers.size() );
256 }
257 }
258 }
259
260
263 public void unsubscribe( Subscriber subscriber ) {
264
265 if ( !eventClass.isAssignableFrom( subscriber.getEventType() ) ) {
266 throw new RuntimeException ("Invalid event type " + subscriber.getEventType()
267 +" for unsubscribing " + subscriber);
268 }
269 if ( subscribers.contains( subscriber ) ) {
270 subscribers.remove( subscriber );
271 if ( getLogger().isDebugEnabled() ) {
272 getLogger().debug( "Unsubscribed Event " + subscriber.getEventType().getName() );
273 getLogger().debug( "Subscribers now active: " + subscribers.size() );
274 }
275 } else {
276 getLogger().warn( "Subscriber " + subscriber + " not found" );
277 }
278 }
279
280
283 public void processEvents()
284 throws ProcessingException {
285 if ( this.configuration != null ) {
286 try {
287 this.aspectSelector = (ServiceSelector) this.manager.lookup( EventAspect.ROLE+"Selector");
288 this.chain = new EventAspectChain();
289 this.chain.configure(this.aspectSelector, this.configuration.getChild("event-aspects"));
290 } catch (ConfigurationException ce) {
291 throw new ProcessingException("Unable configure component.", ce);
292 } catch (ServiceException ce) {
293 throw new ProcessingException("Unable to lookup component.", ce);
294 }
295 this.configuration = null;
296 }
297 DefaultEventAspectContext context = new DefaultEventAspectContext(this.chain);
298 EventConverter converter = null;
299 PortalService service = null;
300 try {
301 service = (PortalService)this.manager.lookup(PortalService.ROLE);
302 converter = (EventConverter) this.manager.lookup(EventConverter.ROLE);
303 Publisher publisher = this.getPublisher();
304
305 converter.start();
306
307 context.setEventPublisher( publisher );
309 context.setObjectModel(this.getObjectModel());
310 context.setEventConverter(converter);
311 context.invokeNext( service );
312
313 converter.finish();
314
315 } catch (ServiceException ce) {
316 throw new ProcessingException("Unable to lookup component.", ce);
317 } finally {
318 this.manager.release(converter);
319 this.manager.release(service);
320 }
321
322 }
323
324
327 public void contextualize(Context context)
328 throws ContextException {
329 this.context = context;
330 }
331
332
335 public void send(Event event) {
336 if ( getLogger().isDebugEnabled() ) {
337 getLogger().debug("Publishing event " + event.getClass());
338 }
339 for ( Iterator e = subscribers.iterator(); e.hasNext(); ){
340 Subscriber subscriber = (Subscriber)e.next();
341 if (subscriber.getEventType().isAssignableFrom(event.getClass())
342 && (subscriber.getFilter() == null || subscriber.getFilter().filter(event))) {
343 if ( getLogger().isDebugEnabled() ) {
344 getLogger().info("Informing subscriber "+subscriber+" of event "+event.getClass());
345 }
346 subscriber.inform(event);
347 }
348 }
349 for (Iterator re = receivers.entrySet().iterator(); re.hasNext(); ) {
350 final Map.Entry current = (Map.Entry )re.next();
351 final Receiver receiver = (Receiver)current.getKey();
352 final List methodInfos = (List )current.getValue();
353 boolean found = false;
354 final Iterator ci = methodInfos.iterator();
355 while ( !found && ci.hasNext() ) {
356 final MethodInfo info = (MethodInfo)ci.next();
357 if ( info.eventClass.isAssignableFrom(event.getClass()) ) {
358 if ( getLogger().isDebugEnabled() ) {
359 getLogger().info("Informing receiver "+receiver+" of event "+event.getClass());
360 }
361 try {
362 info.method.invoke(receiver, new Object [] {event, this.service});
363 } catch (Exception ignore) {
364 this.getLogger().warn("Exception during event dispatching on receiver " + receiver
365 +" and event " + event, ignore);
366 }
367 found = true;
368 }
369 }
370 }
371 }
372
373 protected static final class MethodInfo {
374
375 public Class eventClass;
376 public Method method;
377 }
378
379 protected synchronized List introspect(Class receiverClass) {
380 List result = (List )this.receiverClasses.get(receiverClass.getName());
381 if ( result == null ) {
382 result = new ArrayList ();
383 Method [] methods = receiverClass.getMethods();
384 for(int i=0; i<methods.length; i++ ) {
385 final Method current = methods[i];
386 if ( current.getName().equals("inform") ) {
387 final Class [] params = current.getParameterTypes();
388 if ( params.length == 2
389 && params[1].getName().equals(PortalService.class.getName())) {
390 if ( eventClass.isAssignableFrom( params[0] ) ) {
391 MethodInfo info = new MethodInfo();
392 info.eventClass = params[0];
393 info.method = current;
394 result.add(info);
395 }
396 }
397 }
398 }
399 if ( result.size() == 0 ) {
400 result = null;
401 }
402 }
403 return result;
404 }
405
406
409 public void subscribe(Receiver receiver) {
410 List infos = this.introspect(receiver.getClass());
411 if ( infos == null ) {
412 throw new RuntimeException ("Invalid event receiver type: " + receiver);
413 }
414
415 List eventClassesForReceiver = (List )this.receivers.get(receiver);
417 if ( eventClassesForReceiver == null ) {
418 this.receivers.put(receiver, infos);
419 }
420 if ( getLogger().isDebugEnabled() ) {
421 for(int i=0; i<infos.size();i++) {
422 getLogger().debug( "Receiver " + receiver + " subscribed for event: " + ((MethodInfo)infos.get(i)).eventClass.getName() );
423 }
424 }
425 }
426
427
430 public void unsubscribe(Receiver receiver) {
431 if ( getLogger().isDebugEnabled() ) {
432 getLogger().debug( "Receiver " + receiver + " unsubscribed.");
433 }
434 this.receivers.remove(receiver);
435 }
436
437 }
438 |
Popular Tags |
Java API By Example, From Geeks To Geeks.