Welcome to Modeltron, the elements of systems modeling.
All tagged Activity Parameter
A Control Operator is a special type of Action Node which produces a control token on its output Parameter (i.e., activity parameter or action pin). It is commonly used to dictate (i.e., control) the flow of Object Tokens in an Activity. Similarly, it can be used to disable Object Token flow.
Activity Parameters may be bundled together into Parameter Sets. Only one Input Parameter Set may hold tokens and only one Output Parameter Set may hold tokens on an Activity, although a single Activity Parameter may belong to more than one Parameter Set.
The «nobuffer» and «ovewrwrite» stereotypes can be applied to object nodes to model whether incoming tokens are discarded if a token is already present or overwrite the existing token in the object node.
If an Object Node is typed by a Block which possesses a state machine, then an Object Node, Activity Parameter, or Action Pin typed by that Block can require that the State Machine exist in a certain state before an Object Token may be passed.
The «optional» stereotype may be applied to parameters on an activity diagram indicating that the parameter is “not required to have a value for the activity…to begin or end execution.”
If the “IsStream” attribute of an activity parameter is true, then that parameter “may accept values while its behavior is executing” if it is an input parameter or it “may post values while the behavior is executing.”
