How do you handle exceptions and errors with gateways in BPMN?

2 How do you use exclusive gateways for exceptions and errors?

Exclusive gateways are used to model situations where only one of the possible paths can be followed, based on a binary condition or a decision. For example, if a customer order is valid, the process can proceed to payment; if not, the process can end with an error message. Exclusive gateways are marked with an X inside the diamond. To handle exceptions and errors with exclusive gateways, you need to define the condition or decision that triggers the exception or error path, and label the outgoing sequence flows accordingly. For example, you can use an expression such as "Order valid?" or "Payment successful?" and label the sequence flows as "Yes" or "No".

3 How do you use inclusive gateways for exceptions and errors?

Inclusive gateways are used to model situations where one or more of the possible paths can be followed, based on a complex condition or a multiple-choice decision. For example, if a customer order contains multiple items, the process can split into different paths for each item type, and then merge again after processing. Inclusive gateways are marked with a circle inside the diamond. To handle exceptions and errors with inclusive gateways, you need to define the condition or decision that triggers the exception or error path, and label the outgoing sequence flows accordingly. For example, you can use an expression such as "Item type?" and label the sequence flows as "Book", "DVD", "Error".

4 How do you use parallel gateways for exceptions and errors?

Parallel gateways are used to model situations where all of the possible paths must be followed concurrently, without any condition or decision. For example, if a customer order requires confirmation, invoicing, and shipping, the process can split into three parallel paths for each task, and then merge again after completion. Parallel gateways are marked with a plus sign inside the diamond. To handle exceptions and errors with parallel gateways, you need to use intermediate events or subprocesses to capture and handle the exception or error scenarios. For example, you can use an error event or a compensation subprocess to trigger a corrective action or a rollback.

5 How do you use event-based gateways for exceptions and errors?

Event-based gateways are used to model situations where the process flow depends on the occurrence of an external event, rather than a condition or a decision. For example, if a customer order can be cancelled or modified by the customer at any time, the process can split into different paths based on the event that happens first. Event-based gateways are marked with a pentagon inside the diamond. To handle exceptions and errors with event-based gateways, you need to use intermediate events or event subprocesses to represent and handle the exception or error events. For example, you can use a timer event or a message event to trigger a timeout or a notification.