Actions have incoming and outgoing activity edges that specify the flow of control and data to and from other activity nodes. The actions in an activity start when all of the input conditions are met. You can add input pins and output pins to specify values that are passed to and from the action when it starts. "
Each action has a unique name that describes the behavior.
The Rational® UML modeling products provide several different types of actions that you can use when you create an activity diagram to describe a particular workflow. The actions are organized into the following groups in the Palette:
| Type of action | Description |
|---|---|
| Opaque action | Opaque actions are a type of action that you can use to represent implementation information. You can also use them as placeholder actions until you determine the specific type of action to use. |
| Call behavior | Call behaviors are a type of action that you can use to reference behaviors in other activity, state machine, or interaction diagrams in a model. You can also add unspecified call behaviors to activity diagrams, and then specify a type later. Call behaviors reference the behavior, instead of referencing an operation which then invokes a behavior. Input pins and output pins are created for the input and output parameters of the behavior. |
| Call operation | Call operations are actions that you can use to invoke operations in a model. The referenced operation defines a type of behavior, such as a transformation or a query, that the target object can perform. Each call operation has a unique name that is synchronized with the operation that is referenced. A call operation contains the following pins:
Tip: You can change the <<target>> input pin
to a value pin in the Advanced tab of the Properties view
for the call operation to use a constant value as input.
|
| Structured activity | Structured activities are a type of node that you can use to create logical groups of activity nodes and edges. You can add activity nodes and edges to a structured activity; however, these nodes and edges belong only to the structured activity. They are not shared with other structured activities. When a structured activity is invoked, the activity nodes in the structured activity do not start until all of the input data is received. The output data from a structured activity is not available to other nodes in the activity, and flow does not continue through the activity, until all the actions in the structured activity have finished running. Tip: You can change the orientation of the flow of nodes and edges in
a structured activity node by right-clicking in the node; then clicking Vertical
flow.
|
| Accept event | Accept events are a type of action that you can use to represent the processing of an event. This type of action waits for the occurrence of an event that meets specific conditions. |
| Send signal | Send signals are a type of action that creates an instance of a signal from its inputs, and sends it to the target object, which might invoke a state machine transition or another activity. |