*/
package org.opendaylight.controller.sal.binding.api;
+import java.util.EventListener;
+import java.util.concurrent.ExecutorService;
+
+import org.opendaylight.controller.md.sal.common.api.notify.NotificationPublishService;
+import org.opendaylight.yangtools.concepts.ListenerRegistration;
import org.opendaylight.yangtools.yang.binding.Notification;
-public interface NotificationProviderService extends NotificationService {
+/**
+ * Interface for a notification service that provides publish/subscribe capabilities for YANG
+ * modeled notifications. This interface is a combination of the {@link NotificationService} and
+ * {@link NotificationPublishService} interfaces.
+ */
+public interface NotificationProviderService extends NotificationService, NotificationPublishService<Notification> {
+
+ /**
+ * {@inheritDoc}
+ */
+ @Override
+ public void publish(Notification notification);
+
+ /**
+ * {@inheritDoc}
+ */
+ @Override
+ void publish(Notification notification, ExecutorService executor);
+
+ /**
+ * Registers a listener to be notified about notification subscriptions. This
+ * enables a component to know when there is a notification listener subscribed
+ * for a particular notification type.
+ * <p>
+ * On registration of this listener, the
+ * {@link NotificationInterestListener#onNotificationSubscribtion(Class)} method
+ * will be invoked for every notification type that currently has a notification listener
+ * subscribed.
+ *
+ * @param interestListener the listener that will be notified when subscriptions
+ * for new notification types occur.
+ * @return a {@link ListenerRegistration} instance that should be used to unregister the listener
+ * by invoking the {@link ListenerRegistration#close()} method when no longer needed.
+ */
+ ListenerRegistration<NotificationInterestListener> registerInterestListener(
+ NotificationInterestListener interestListener);
+
+ /**
+ * Interface for a listener interested in being notified about notification subscriptions.
+ */
+ public interface NotificationInterestListener extends EventListener {
- void notify(Notification notification);
+ /**
+ * Callback that is invoked when a notification listener subscribes for a
+ * particular notification type.
+ * <p>
+ * This method is only called for the first subscription that occurs for a
+ * particular notification type. Subsequent subscriptions for the same
+ * notification type do not trigger invocation of this method.
+ * <p>
+ * <b>Note:</b>This callback is delivered from thread not owned by this listener,
+ * all processing should be as fast as possible and implementations should
+ * not do any blocking calls or block this thread.
+ *
+ * @param notificationType the notification type for the subscription that occurred.
+ */
+ void onNotificationSubscribtion(Class<? extends Notification> notificationType);
+ }
}