A business process must have at least one receive activity connected to start the process.
You design a Receive activity using a <<Receive>> business process. To create a <<Receive>> business process you can right-click an <<Undefined>> process and select Change to Receive in the contextual menu. You can also select the <<Receive>> stereotype in the process property sheet.
The <<Receive>> stereotype is associated with an event handler that automatically performs the following actions in the model:
Sets the implementation type of the process to Execute operation
Creates a new One Way operation together with an input message. The word "Receive" is displayed before the name of this operation
Sets the Action type to Receive request
Creates a new variable in the Message mapping box of the received message with the same name as the received message format