Subscribing to Entity Events

While editing an entity object with the Entity Object Editor, you can use the Subscribe page to select the events (defined in the project) that the entity object will listen for. When the event is triggered, the entity object responds by calling the specified method. You can specify how the event will be delivered: deliver the event to the instances of the entity object as subscribed in program logic (addListener), or to those entity objects that are associated to the publisher, by the selected association.

Field

Description

Published Events

This pane displays a tree of available events to which the entity object can subscribe. To choose an event from the list, click its name and click the right-arrow. JDeveloper displays the name in the Subscribed Events list. If you defined an event that does not appear on the Published Events list, go back to the Publish Event panel, select an event, and click Apply.

Subscribed Events

This pane displays a tree of publishers and their events that are currently subscribed to by this entity object. To remove an event from the list, click its name, and then click the left arrow.

Deliver Events

Use the Deliver Events grouping to specify how the event will be delivered. You can deliver the event to the instances of the entity as subscribed in program logic, or to those entities that are associated to the publisher, by the selected association.

To subscribing Entities

Registered in program

If you select this option, custom logic will have to be implemented to link a subscribing entity instance with a publisher instance.

Associated to Publisher

If you select this option, all instances of this entity are automatically linked to their respective publisher entity as defined by the selected association accessor.

By

Select an association accessor from this list. The available association accessors get their subscribing entity type from the publisher. For example, if an Emp entity object is subscribing to LocChanged on a Dept entity object, all associations between Dept and Emp that return Emp would be on this list.

By invoking methods

An ordered list of selected methods that can be called on the subscriber when the selected event is received. Click a method to select it.

Add

Opens the Define Method dialog box where you define a new method to call when the selected event is received. Methods defined in this way appear in the Methods list.

Edit

Opens the Subscribe dialog box in which you can edit the selected method.

Remove

Removes the selected method.

Arrow Keys

Use the arrow keys to reorder the list.

Field	Description
Published Events	This pane displays a tree of available events to which the entity object can subscribe. To choose an event from the list, click its name and click the right-arrow. JDeveloper displays the name in the Subscribed Events list. If you defined an event that does not appear on the Published Events list, go back to the Publish Event panel, select an event, and click Apply.
Subscribed Events	This pane displays a tree of publishers and their events that are currently subscribed to by this entity object. To remove an event from the list, click its name, and then click the left arrow.
Deliver Events	Use the Deliver Events grouping to specify how the event will be delivered. You can deliver the event to the instances of the entity as subscribed in program logic, or to those entities that are associated to the publisher, by the selected association.
To subscribing Entities
Registered in program	If you select this option, custom logic will have to be implemented to link a subscribing entity instance with a publisher instance.
Associated to Publisher	If you select this option, all instances of this entity are automatically linked to their respective publisher entity as defined by the selected association accessor.
By	Select an association accessor from this list. The available association accessors get their subscribing entity type from the publisher. For example, if an Emp entity object is subscribing to `LocChanged` on a Dept entity object, all associations between Dept and Emp that return `Emp` would be on this list.
By invoking methods	An ordered list of selected methods that can be called on the subscriber when the selected event is received. Click a method to select it.
Add	Opens the Define Method dialog box where you define a new method to call when the selected event is received. Methods defined in this way appear in the Methods list.
Edit	Opens the Subscribe dialog box in which you can edit the selected method.
Remove	Removes the selected method.
Arrow Keys	Use the arrow keys to reorder the list.