Model Parts, Diagrams, Dictionary Items, and Properties > Dictionary items > Read link action (dictionary item)
Read link action (dictionary item)
For automation interface information about a Read Link Action, see Action node.
For automation interface purposes, a Read Link Action is an Action Node that has its Node Type set to Read Link Action.
A Read Link Action is a link action that navigates across associations to retrieve objects on one end.
Create a Read Link Action through a Modeler explorer pane or an Activity Diagram:
• In a Modeler pane, right-click an Activity or Structured Activity Node, and select New > Action Node > Read Link Action.
• On an Activity Diagram tab: click the Read Link Action button, and then click in free space or inside an Activity Partition, Interruptible Activity Region or Structured Activity Node.
To access the Read Link Action button, click the arrow next to the Read Self Action button and then select the Read Link Action button.
When you create a Read Link Action, you are prompted to select the Association that is read by the action. After creating a Read Link Action you cannot link that Read Link Action to a different Association. You can view which Association is linked to a Read Link Action through the Read Link Action's property pages: on the Items tab, select Linked Item.
On creation of a Read Link Action, Modeler creates an Input Pin and an Output Pin:
• The Input Pin is created for the source Role of the Association that is linked to the Read Link Action. The name of this Input Pin is set to that of the source Role, and the Input Pin's data type is set to the source item of the Association that is linked to the Read Link Action.
• The Output Pin is created for the end Role of the Association that is linked to the Read Link Action. The name of this Output Pin is set to Result Pin, and the Output Pin's data type is set to the destination item of the Association that is linked to the Read Link Action.
You cannot delete the Input Pin or Output Pin, and you cannot create any other Input Pins or Output Pins on a Read Link Action.
Modeler ensures that the name of the Input Pin matches the name of its Linked Item:
• If you change the name of the Input Pin, Modeler changes to the name of the Linked Item (source Role) to match.
• If you change the name of an Input Pin's Linked Item (source Role), Modeler changes the name of the Input Pin to match.
When used on an Activity Diagram, a Read Link Action's notation is as follows.
The View Options on an Activity Diagram allow you to show or hide the Name, Action Type and Linked Item Name. By default, the Action Type and Linked Item Name are shown. The view options are set through the Action Node entry. See Action node view options - activity diagram.
On an Activity Diagram, you can populate a Read Link Action's missing Activity Flows, Output Pins, Comments and Constraints: right-click the Read Link Action, point to Populate, and then click the appropriate command.
In the Dictionary pane, Read Link Actions are listed in the UML\Action Nodes folder.
In the Modeler panes, a short-cut symbol on the Read Link Action's icon indicates that the item is a stub.
The following sections provide information about how a Read Link Action is used in the model.
Properties
In addition to the standard properties a Read Link Action has these properties:
Owned by
Activity - The Activity that scopes the Read Link Action.
Structured Activity Node- Applies only when the Read Link Action is scoped directly to a Structured Activity Node.
Owns
Comment
Constraint
Control Flow - The Control Flow is owned jointly by the Read Link Action and the associated item. The access permissions you have to a Control Flow are determined by the access permissions you have to its source item.
Dependency - The Dependency is owned jointly by the Read Link Action and the other associated item. The access permissions you have to a Dependency are determined by the access permissions of the dependent item.
Exception Handler - The Exception Handler is owned jointly by the Read Link Action and the associated item. The access permissions you have to an Exception Handler are determined by the access permissions you have to its source item.
Input Pin - Only the Input Pin that Modeler creates on creation of the Read Link Action.
IO Flow - The IO Flow is owned jointly by the Read Link Action, the IO Flow's other linked item and the IO Flow's IO Item.
Output Pin - Only the Result Pin that Modeler creates on creation of the Read Link Action.
Defined in these parts of the model
Activity Model
Shown on these diagrams
Activity Diagram
Variant Diagram
Can be linked to these dictionary items
In addition to the owning Activity or Structured Activity Node, a Read Link Action can be linked to the following items.
Stereotype To make a Read Link Action valid for a Stereotype, set up Action Node a valid item type.
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Like most other items in a Model, a Read Link Action can be linked to an Activity Partition, Comment, Frame Box, General Node, General Flow, Constraint (applied), General Flow Diagram Flow or Swimlane.