/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
package org.apache.lenya.cms.observation;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import org.apache.avalon.framework.logger.AbstractLogEnabled;
import org.apache.avalon.framework.thread.ThreadSafe;
import org.apache.lenya.cms.publication.Document;
import org.apache.lenya.cms.publication.DocumentIdentifier;
import org.apache.lenya.util.Assert;
/**
* Observation manager. Works as an observation registry and sends the notifications.
*/
public class ObservationManager extends AbstractLogEnabled implements ObservationRegistry,
ThreadSafe {
private Map identifier2listeners = new HashMap();
private Set listeners = new HashSet();
public synchronized void registerListener(RepositoryListener listener, Document doc)
throws ObservationException {
Set listeners = getListeners(doc.getIdentifier());
if (listeners.contains(listener)) {
throw new ObservationException("The listener [" + listener
+ "] is already registered for the document [" + doc + "].");
}
listeners.add(listener);
}
protected Set getListeners(DocumentIdentifier doc) {
Set listeners = (Set) this.identifier2listeners.get(doc);
if (listeners == null) {
listeners = new HashSet();
this.identifier2listeners.put(doc, listeners);
}
return listeners;
}
public synchronized void registerListener(RepositoryListener listener)
throws ObservationException {
if (this.listeners.contains(listener)) {
throw new ObservationException("The listener [" + listener + "] is already registered.");
}
this.listeners.add(listener);
}
protected DocumentIdentifier getIdentifier(DocumentEvent event) {
Assert.notNull("event", event);
DocumentIdentifier id = new DocumentIdentifier(event.getPublicationId(), event.getArea(),
event.getUuid(), event.getLanguage());
return id;
}
protected Set getAllListeners(DocumentIdentifier doc) {
Set allListeners = new HashSet();
synchronized (this) {
allListeners.addAll(this.listeners);
allListeners.addAll(getListeners(doc));
}
return allListeners;
}
protected void notify(Set listeners, RepositoryEvent event) {
for (Iterator i = listeners.iterator(); i.hasNext();) {
RepositoryListener listener = (RepositoryListener) i.next();
listener.eventFired(event);
}
}
public void eventFired(RepositoryEvent event) {
Assert.notNull("event", event);
Set listeners;
if (event instanceof DocumentEvent) {
DocumentIdentifier id = getIdentifier((DocumentEvent) event);
listeners = getAllListeners(id);
} else {
listeners = this.listeners;
}
notify(listeners, event);
}
}