NotificationQueue
The NotificationQueue is used by the notification service to queue requests to generate and send notifications (policy and subscription based notifications).
There are two types of subscriptions/notifications supported by the notification service:
• Email subscriptions/notifications
• Object Listener subscriptions/notifications
These are subscriptions that can be created where the subscription "recipient" is a Windchill object that implements the wt.notify.ObjectSubscriptionListener interface. WfSynchRobot is one of these objects. Additionally, the Discussion Forum, Discussion Topic and Discussion Posting interfaces implement this. Whenever these Object Listener subscriptions are satisfied, instead of an email being sent to a user, the notification service invokes a method on the subscription's ObjectSubscriptionListener "recipient" object and the object does whatever processing is desired.
The NotificationQueue is used for both the e-mail subscriptions and the Object Listener subscriptions; therefore, NotificationQueue must be started for WfSynchRobots to be notified so they can do the desired processing when their subscriptions are satisfied. Stopping the NotificationQueue prevents email notifications from being sent and it prevents Object Listener subscribers from functioning.