Package gov.usgs.earthquake.distribution

Interface NotificationReceiver

All Superinterfaces:

Configurable

All Known Implementing Classes:

AwsProductReceiver, DefaultNotificationReceiver, EIDSNotificationReceiver, EIDSProductReceiver, NATSStreamingNotificationReceiver, SocketProductReceiver, WebSocketNotificationReceiver

public interface NotificationReceiver
extends Configurable

Receives and processes notifications. A NotificationReceiver receives and processes notifications, alerting NotificationListeners after they are processed.

Method Summary

Modifier and Type	Method	Description
void	addNotificationListener(NotificationListener listener)	Add a NotificationListener.
void	receiveNotification(Notification notification)	Receive and process a notification.
void	removeExpiredNotifications()	If a NotificationReceiver stores notifications, all expired notifications and products should be removed when this method is called.
void	removeNotificationListener(NotificationListener listener)	Remove a NotificationListener.
Product	retrieveProduct(ProductId id)	NotificationListeners use this method to request a product.
void	sendNotifications(NotificationListener listener, java.util.List<java.lang.String> sources, java.util.List<java.lang.String> types, java.util.List<java.lang.String> codes)	Send matching notifications to the listener.

Methods inherited from interface gov.usgs.util.Configurable

configure, getName, setName, shutdown, startup

Method Detail

receiveNotification

void receiveNotification(Notification notification)
                  throws java.lang.Exception

Receive and process a notification.

Parameters:

notification - the notification being received.

Throws:

java.lang.Exception - if errors occur.

removeExpiredNotifications

void removeExpiredNotifications()
                         throws java.lang.Exception

If a NotificationReceiver stores notifications, all expired notifications and products should be removed when this method is called.

Throws:

java.lang.Exception - if errors occur while removing expired notifications.

retrieveProduct

Product retrieveProduct(ProductId id)
                 throws java.lang.Exception

NotificationListeners use this method to request a product. A NotificationReceiver may have many listeners, and should try to retrieve products once for each product id. This will typically generate a "local" notification, that, when expiring, signals the product may be removed.

Parameters:

id - the product to retrieve.

Returns:

the retrieved product, or null if not available.

Throws:

java.lang.Exception - if an error occurs while retrieving the product.

addNotificationListener

void addNotificationListener(NotificationListener listener)
                      throws java.lang.Exception

Add a NotificationListener. Notifications processed after this call will be sent to listener.

Parameters:

listener - the listener to add.

Throws:

java.lang.Exception - if errors occur.

removeNotificationListener

void removeNotificationListener(NotificationListener listener)
                         throws java.lang.Exception

Remove a NotificationListener. Notifications processed after this call will not be sent to listener.

Parameters:

listener - the listener to remove.

Throws:

java.lang.Exception - if errors occur.

sendNotifications

void sendNotifications(NotificationListener listener,
                       java.util.List<java.lang.String> sources,
                       java.util.List<java.lang.String> types,
                       java.util.List<java.lang.String> codes)
                throws java.lang.Exception

Send matching notifications to the listener. This method is a way for listeners to search notifications that were processed while not an active listener. If sources, types, and codes are all null, a notifications for each known ProductId will be sent to listener. For example, a new shakemap NotificationListener may wish to know about all known shakemaps.

 NotificationListener shakemapListener;
 // register to receive new notifications as they arrive
 receiver.addNotificationListener(shakemapListener);
 // check if any notifications haven't already been processed.
 List<String> types = new LinkedList<String>();
 types.add("shakemap");
 types.add("shakemap-scenario");
 receiver.sendNotifications(shakemapListener, null, types, null);
 

Parameters:

listener - the listener that will receive any matching notifications.

sources - a list of sources to search, or null for all sources.

types - a list of types to search, or null for all types.

codes - a list of codes to search, or null for all codes.

Throws:

java.lang.Exception - if errors occur.