ddf.catalog.event

Interface EventProcessor

All Known Implementing Classes:

EventProcessorImpl, FanoutEventProcessor

public interface EventProcessor

This interface is used to describe:

• a method of creating, updating, and deleting subscriptions.
• a method of broadcasting events when Metacards are created, updated, or deleted.

Author:

ddf.isgs@lmco.com

Field Summary

Fields

Modifier and Type	Field and Description
static String	EVENT_METACARD Deprecated. This constant is implementation specific and will be removed from API
static String	EVENT_OLD_METACARD Deprecated. This constant is implementation specific and will be removed from API
static String	EVENT_TIME Deprecated. This constant is implementation specific and will be removed from API
static String	EVENTS_TOPIC_CREATED Deprecated. This constant is implementation specific and will be removed from API
static String	EVENTS_TOPIC_DELETED Deprecated. This constant is implementation specific and will be removed from API
static String	EVENTS_TOPIC_UPDATED Deprecated. This constant is implementation specific and will be removed from API

Method Summary

Modifier and Type	Method and Description
String	createSubscription(Subscription subscription) Create a Subscription with an automatically-generated id.
void	createSubscription(Subscription subscription, String subscriptionId) Register a Subscription with this CatalogFramework.
void	deleteSubscription(String subscriptionId) Deletes the subscription associated with the given id.
void	notifyCreated(Metacard newMetacard) Notify this EventProcessor that a Metacard (or equivalent) has been created in a RemoteSource.
void	notifyDeleted(Metacard oldMetacard) Notify this EventProcessor that a Metacard (or equivalent) has been deleted in a RemoteSource.
void	notifyUpdated(Metacard newMetacard, Metacard oldMetacard) Notify this EventProcessor that a Metacard (or equivalent) has been updated in a RemoteSource.
void	updateSubscription(Subscription subscription, String subcriptionId) Updates the subscription associated with the given id.

Field Detail

EVENT_METACARD

static final String EVENT_METACARD

Deprecated. This constant is implementation specific and will be removed from API

See Also:

Constant Field Values

EVENT_OLD_METACARD

static final String EVENT_OLD_METACARD

Deprecated. This constant is implementation specific and will be removed from API

See Also:

Constant Field Values

EVENT_TIME

static final String EVENT_TIME

Deprecated. This constant is implementation specific and will be removed from API

See Also:

Constant Field Values

EVENTS_TOPIC_CREATED

static final String EVENTS_TOPIC_CREATED

Deprecated. This constant is implementation specific and will be removed from API

See Also:

Constant Field Values

EVENTS_TOPIC_UPDATED

static final String EVENTS_TOPIC_UPDATED

Deprecated. This constant is implementation specific and will be removed from API

See Also:

Constant Field Values

EVENTS_TOPIC_DELETED

static final String EVENTS_TOPIC_DELETED

Deprecated. This constant is implementation specific and will be removed from API

See Also:

Constant Field Values

Method Detail

createSubscription

String createSubscription(Subscription subscription)
                   throws InvalidSubscriptionException

Create a Subscription with an automatically-generated id.

Parameters:

subscription - the Subscription to register

Returns:

String an id for the registered Subscription that can be used later by calling #unsubscribe(String)

Throws:

InvalidSubscriptionException - if this EventProcessor can not support the Filter of the provided Subscription.

See Also:

createSubscription(Subscription, String)

createSubscription

void createSubscription(Subscription subscription,
                        String subscriptionId)
                 throws InvalidSubscriptionException,
                        SubscriptionExistsException

Register a Subscription with this CatalogFramework.

Note: Subscriptions are transient, not durable, i.e., only maintained in memory and will be lost if DDF is shutdown.
Durability must be implemented by the client bundle (typically an endpoint - refer to DurableSubscription for an example).

Note: A Subscription can also be registered using the whiteboard model:
To register a Subscription via the whiteboard model, simply register any implementation of Subscription with OSGi registry under the interface Subscription. To unregister the Subscription, simply unregister the service that was originally registered. Subscriptions registered in this manner do not get a subscription id and cannot be unsubscribed via the EventProcessor Implementations of this method must call the PreSubscriptionPlugin.process(Subscription) method for each

Parameters:

subscription - the Subscription to register

subscriptionId - the desired id

Throws:

InvalidSubscriptionException - if this EventProcessor can not support the Filter of the provided Subscription.

SubscriptionExistsException - if a subscription with this ID already exists

updateSubscription

void updateSubscription(Subscription subscription,
                        String subcriptionId)
                 throws SubscriptionNotFoundException

Updates the subscription associated with the given id.

Parameters:

subscription - the subscription to update

subcriptionId - the subscription id to identify the subscription

Throws:

SubscriptionNotFoundException - if the subscription was not found

deleteSubscription

void deleteSubscription(String subscriptionId)
                 throws SubscriptionNotFoundException

Deletes the subscription associated with the given id.

Parameters:

user - deleting the subscription

subscriptionId - the subscription id to identify the subscription to delete

Throws:

SubscriptionNotFoundException - if the subscription was not found

notifyCreated

void notifyCreated(Metacard newMetacard)

Notify this EventProcessor that a Metacard (or equivalent) has been created in a RemoteSource.

Implementations of this method must:

1. Call the PreDeliveryPlugin.processCreate(Metacard) method for all of the registered PreDeliveryPlugins
2. Call the DeliveryMethod.created(Metacard) method of the DeliveryMethod of matching Subscriptions with the new Metacard created.

Parameters:

newMetacard - the newly created Metacard

See Also:

RemoteSource, FederatedSource, ConnectedSource

notifyUpdated

void notifyUpdated(Metacard newMetacard,
                   Metacard oldMetacard)

Notify this EventProcessor that a Metacard (or equivalent) has been updated in a RemoteSource.

Implementations of this method must:

1. Call PreDeliveryPlugin.processUpdateHit(ddf.catalog.operation.Update) method of all registered PreDeliveryPlugins when a Metacard has been updated and the new version matches a Subscription
2. Call PreDeliveryPlugin.processUpdateMiss(ddf.catalog.operation.Update) method of all registered PreDeliveryPlugins when a Metacard has been updated and the new version matches a Subscription but the old version does not
3. Call all registered implementations of DeliveryMethod with the updated Metacard.

Parameters:

newMetacard - the new version of the Metacard

oldMetacard - the previous version of the Metacard (optional, pass null if not relevant)

See Also:

FederatedSource, RemoteSource, ConnectedSource

notifyDeleted

void notifyDeleted(Metacard oldMetacard)

Notify this EventProcessor that a Metacard (or equivalent) has been deleted in a RemoteSource.

Implementations of this method must:

If possible (that is, the Metacard is fully populated) call all active matching Subscriptions associated DeliveryMethod.deleted(Metacard) with the Metacard that was deleted. If impossible (this is, the Metacard only has Metacard.getId(), call all active Subscriptions.

Parameters:

oldMetacard - the deleted Metacard

See Also:

RemoteSource, FederatedSource, ConnectedSource