The case when there is a transfer of items between actions that may itself take time or have modeled properties can be modeled using the following options:
- A flow connection represents a flow in which the transfer can be ongoing while both the source and target action are being performed.
- A succession flow connection represents a flow that imposes the additional succession constraint that the transfer cannot begin until the source action completes and the target action cannot start until the transfer has completed.
- Transfers can also be performed using send and accept action usages. In this case, the source and target of the transfer do not have to be explicitly connected with a flow. Instead, the source of the transfer is specified using a send action usage contained in some source part or action, while the target is given by an accept action usage in some destination part or action. A send action usage includes an expression that is evaluated to provide the values to be transferred, and it specifies the destination to which those values are to be sent. An accept action usage specifies the type of values that can be received by the action. When a send action performed in the source is matched with a compatible accept action performed in the destination, then the transfer of values from the origin to the destination can be completed.