How does a variable take a value before the XOR gateway evaluation?

BPMN & Modeling Discussion & Questions
1

Hi to all.

In the following BPMN diagram, there is a XOR gateway which evaluates the value of a variable named “newProductNeeded”.

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Based on here Data-based Exclusive Gateway (XOR) | docs.camunda.org,
I’ve defined the expression for the 2 outgoing sequence flows as “true” in the one case and “false” in the other one.

I suppose that I must write an expression or script in the incoming sequence flow of XOR gateway but I don’t find the way in Docs.

Does anyone know sth on this please?

Thanks in advance,
Steve

2

Hi Steve,

This is where process variables are useful. Conditions like this typically refer to process variables. This reference [1] on process variables may be of interest.

The expression notation is a shorthand way of accessing these process variables. Hence if you had a process variable called CART_ITEM_COUNT, a conditional expression could be ${CART_ITEM_COUNT > 0}

regards

Rob

[1] https://docs.camunda.org/manual/7.9/user-guide/process-engine/variables/

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