/*
* Copyright 2002-2007 the original author or authors.
*
* 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.springframework.jmx.export.notification;
import javax.management.AttributeChangeNotification;
import javax.management.MBeanException;
import javax.management.Notification;
import javax.management.ObjectName;
import javax.management.modelmbean.ModelMBean;
import javax.management.modelmbean.ModelMBeanNotificationBroadcaster;
import org.springframework.util.Assert;
/**
* {@link NotificationPublisher} implementation that uses the infrastructure
* provided by the {@link ModelMBean} interface to track
* {@link javax.management.NotificationListener javax.management.NotificationListeners}
* and send {@link Notification Notifications} to those listeners.
*
* @author Rob Harrop
* @author Juergen Hoeller
* @author Rick Evans
* @since 2.0
* @see javax.management.modelmbean.ModelMBeanNotificationBroadcaster
* @see NotificationPublisherAware
*/
public class ModelMBeanNotificationPublisher implements NotificationPublisher {
/**
* The {@link ModelMBean} instance wrapping the managed resource into which this
* <code>NotificationPublisher</code> will be injected.
*/
private final ModelMBeanNotificationBroadcaster modelMBean;
/**
* The {@link ObjectName} associated with the {@link ModelMBean modelMBean}.
*/
private final ObjectName objectName;
/**
* The managed resource associated with the {@link ModelMBean modelMBean}.
*/
private final Object managedResource;
/**
* Create a new instance of the {@link ModelMBeanNotificationPublisher} class
* that will publish all {@link javax.management.Notification Notifications}
* to the supplied {@link ModelMBean}.
* @param modelMBean the target {@link ModelMBean}; must not be <code>null</code>
* @param objectName the {@link ObjectName} of the source {@link ModelMBean}
* @param managedResource the managed resource exposed by the supplied {@link ModelMBean}
* @throws IllegalArgumentException if any of the parameters is <code>null</code>
*/
public ModelMBeanNotificationPublisher(
ModelMBeanNotificationBroadcaster modelMBean, ObjectName objectName, Object managedResource) {
Assert.notNull(modelMBean, "'modelMBean' must not be null");
Assert.notNull(objectName, "'objectName' must not be null");
Assert.notNull(managedResource, "'managedResource' must not be null");
this.modelMBean = modelMBean;
this.objectName = objectName;
this.managedResource = managedResource;
}
/**
* Send the supplied {@link Notification} using the wrapped
* {@link ModelMBean} instance.
* @param notification the {@link Notification} to be sent
* @throws IllegalArgumentException if the supplied <code>notification</code> is <code>null</code>
* @throws UnableToSendNotificationException if the supplied <code>notification</code> could not be sent
*/
public void sendNotification(Notification notification) {
Assert.notNull(notification, "Notification must not be null");
replaceNotificationSourceIfNecessary(notification);
try {
if (notification instanceof AttributeChangeNotification) {
this.modelMBean.sendAttributeChangeNotification((AttributeChangeNotification) notification);
}
else {
this.modelMBean.sendNotification(notification);
}
}
catch (MBeanException ex) {
throw new UnableToSendNotificationException("Unable to send notification [" + notification + "]", ex);
}
}
/**
* From the {@link Notification javadoc}:
* <p><i>"It is strongly recommended that notification senders use the object name
* rather than a reference to the MBean object as the source."</i>
* @param notification the {@link Notification} whose
* {@link javax.management.Notification#getSource()} might need massaging
*/
private void replaceNotificationSourceIfNecessary(Notification notification) {
if (notification.getSource() == null || notification.getSource().equals(this.managedResource)) {
notification.setSource(this.objectName);
}
}
}