Modeling event gateways

Use an event gateway to model a point in the process execution where only one of several paths can be followed, depending on events that occur.

Before you begin

To perform this task, you must be in the IBM® Process Designer desktop editor.

About this task

An event gateway represents a branching point in a process execution where only one of several paths can be followed, depending on events that occur. A specific event, such as the receipt of a message or timer event, determines the path that will be taken. The event gateway represents a single point of behavior that is spread out across multiple process components connected by sequence flow. The following types of events can directly follow an event gateway (connected by a single sequence flow):

  • Intermediate message event (receiving)
  • Intermediate timer event

When creating an event gateway, you must connect at least two intermediate events to the gateway. And, when connected to an event gateway, an intermediate event is not allowed to have additional incoming sequence flow.

Procedure

  1. Open the Process Designer desktop editor.
  2. Open a business process definition (BPD).
  3. Drag a gateway from the palette to the process diagram.
  4. In the text box that displays over the gateway, type a name for the gateway.
  5. Click the General option in the properties.
  6. In the Behavior section of the general properties, click the drop-down list and select Event Gateway from the available gateway types. To streamline configuration of an event gateway, IBM Process Designer automatically adds an intermediate message event (receiving) and an intermediate timer event to the process diagram. These intermediate events are grouped with the event gateway in the process diagram.
  7. Add any additional events required by the gateway configuration by dragging them from the palette to the event gateway group in the process diagram. Only intermediate message events and intermediate timer events are allowed. The minimum number of events is two, and you can add as many as you require.
  8. Click an event in the group and then select the Implementation option in the properties.
    1. To configure an intermediate message event, follow the steps in Using intermediate and boundary message events to receive messages.
    2. To configure an intermediate timer event, follow the steps in Modeling delays, escalations, and timeouts.
Parent topic: Modeling events