Using ''contains/includes" expression for a bpmn:conditionExpression

Camunda 7 Topics Discussion & Questions
1

Hi,
i’m trying to create a bpmn:conditionExpression with contains/includes expression, for example
<bpmn:conditionExpression xsi:type=“bpmn:tFormalExpression”>${(persons.includes(person))}</bpmn:conditionExpression>

is it possible to create such a condition?

2

Hi @Elia_Rohana,

It really depends how and where you use expressions. If you’re using the Spring Framework, you can check this docs page. You can also have a look at this docs page to get a better understanding of how Camunda uses expressions.

Otherwise, can you provide more context to your problem? Ex. what is your setup/environment, how is the persons entity created, etc.

Best,
Nikola

3

Hi,
we are developing kind of tree decision applicaiton using BPMN, the user builds the bpmn process(tree) dynamically and create a condition using a componenet we developed in our company, then we translate it into a bpmn expression.

thus all our expression are part of the xml, and are using process variables (e.g. persons is a process variables)

till now we used simple condition, something like

  • person.age > 50

  • person.age > 50 and person.gender == male

whenwe had only on person as process variable, it was working ok with the following:

<sequenceFlow>
    <conditionExpression xsi:type="tFormalExpression">
      ${person.age > '50'}
    </conditionExpression>
  </sequenceFlow>

but for more complicated expression i couldn’t find any reference on what are the capabilities of the expression language. it would be helpful if you give me some guide on what i can i acheive using the expression language.

so when i say i want to create an expression of persons.search(criteria) where persons is a proces variable, and criteria is created by the user, e.g. person.age > 50 and gender == male, i don’t see how i’m able to do it.

does that provide my context to the problem ?

4

Hi @Elia_Rohana,

at the top of this page https://docs.camunda.org/manual/7.10/user-guide/process-engine/expression-language/#usage-of-expression-language you can find some links to external references about the specification, examples and the implementaion of JUEL embedded in the Camunda engine.

I always find it helpful to create a JUnit test to get immediate feedback about the evaluation: https://docs.camunda.org/manual/7.10/user-guide/process-engine/process-instance-modification/#process-instance-modification-in-junit-tests

Hope this helps, Ingo

5