DelegatingSystemEventListener.java

/*
 * JBoss, Home of Professional Open Source
 * Copyright 2011, Red Hat, Inc., and individual contributors
 * by the @authors tag. See the copyright.txt in the distribution for a
 * full listing of individual contributors.
 *
 * Licensed 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.jboss.seam.faces.event;

import java.util.List;

import javax.faces.event.AbortProcessingException;
import javax.faces.event.PreDestroyApplicationEvent;
import javax.faces.event.SystemEvent;
import javax.faces.event.SystemEventListener;

import org.jboss.solder.logging.Logger;

/**
 * Provide CDI injection to SystemEventListener artifacts by delegating through this class.
 *
 * @author <a href="mailto:lincolnbaxter@gmail.com>Lincoln Baxter, III</a>
 */
public class DelegatingSystemEventListener extends AbstractListener<SystemEventListener> implements SystemEventListener {
    private transient final Logger log = Logger.getLogger(DelegatingSystemEventListener.class);

    @Override
    public boolean isListenerForSource(final Object source) {
        return true;
    }

    @Override
    public void processEvent(final SystemEvent event) throws AbortProcessingException {
        if (event instanceof PreDestroyApplicationEvent && !isBeanManagerAvailable()) {
            log.info("BeanManager no longer available; Cannot notify CDI-managed listeners of "
                    + PreDestroyApplicationEvent.class.getSimpleName());
            return;
        }

        for (SystemEventListener l : getEventListeners()) {
            if (l.isListenerForSource(event.getSource())) {
                l.processEvent(event);
            }
        }
    }

    @SuppressWarnings("unchecked")
    private List<SystemEventListener> getEventListeners() {
        return getListeners(SystemEventBridge.class);
    }

}