Find all subscriptions that should receive the given message. The map returned is safe to iterate and will never be modified. @param message the message @return a {@code MultiValueMap} with sessionId-subscriptionId pairs (possibly empty)
Register a subscription represented by the given message. @param subscribeMessage the subscription request
Remove all subscriptions associated with the given sessionId.
Unregister a subscription. @param unsubscribeMessage the request to unsubscribe
A registry of subscription by session that allows looking up subscriptions.
@author Rossen Stoyanchev @since 4.0