/*
* 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.tuscany.sca.core.event;
import java.util.List;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.CopyOnWriteArrayList;
import org.apache.tuscany.sca.event.Event;
import org.apache.tuscany.sca.event.EventFilter;
import org.apache.tuscany.sca.event.EventPublisher;
import org.apache.tuscany.sca.event.RuntimeEventListener;
import org.apache.tuscany.sca.event.TrueFilter;
/**
* Base implementation of an EventPublisher
*
* @version $Rev$ $Date$
*/
public abstract class BaseEventPublisher implements EventPublisher {
protected static final EventFilter TRUE_FILTER = new TrueFilter();
protected Map> listeners;
public void addListener(RuntimeEventListener listener) {
addListener(TRUE_FILTER, listener);
}
public void removeListener(RuntimeEventListener listener) {
assert listener != null : "Listener cannot be null";
synchronized (getListeners()) {
for (List currentList : getListeners().values()) {
for (RuntimeEventListener current : currentList) {
if (current == listener) {
currentList.remove(current);
return;
}
}
}
}
}
public void addListener(EventFilter filter, RuntimeEventListener listener) {
assert listener != null : "Listener cannot be null";
synchronized (getListeners()) {
List list = getListeners().get(filter);
if (list == null) {
list = new CopyOnWriteArrayList();
listeners.put(filter, list);
}
list.add(listener);
}
}
public void publish(Event event) {
assert event != null : "Event object was null";
for (Map.Entry> entry : getListeners().entrySet()) {
if (entry.getKey().match(event)) {
for (RuntimeEventListener listener : entry.getValue()) {
listener.onEvent(event);
}
}
}
}
protected Map> getListeners() {
if (listeners == null) {
listeners = new ConcurrentHashMap>();
}
return listeners;
}
}