Rules in jBPM 6

Question

I have created a process in jbpm 6. There is a class Person, with attributes name and age. In the process form, the name and age of the person is entered. The first node in the process is a human task to view the details. The second node is an XOR gateway with drools expression on its arcs like Person(age > 20) and Person (age < 20).

Now when I execute the process instance, the first human tasks works fine, but when it reaches the gateway, I can see this error -

"XOR split could not find at least one valid outgoing connection for split Gateway".

Any idea whats wrong.

Answer 1

Gateways containing drools expressions only work with facts and not with process variables. If you want to make use of a drools expression in your gateways, you will need to insert the process variable (or the whole process instance) as a fact. You can do so by using a script node, an outgoing action in your human task.

From documentation:

Rule constraints do not have direct access to variables defined inside the process. It is however possible to refer to the current process instance inside a rule constraint, by adding the process instance to the Working Memory and matching for the process instance in your rule constraint. ....... Note that you are however responsible yourself to insert the process instance into the session and, possibly, to update it, for example, using Java code or an on-entry or on-exit or explicit action in your process.

Hope it helps,