Summary

When you execute a rule in a task where no data has been previously registered in the process entity, you can have an error in the execution of the rule.

Applies to

Bizagi 11.X versions

Symptoms

When you execute a rule that returns null, for example, you want to get the size of a collection that is empty in a form:

 Using the following rule On Save:

var  object  =   Me . getXPath ( "ProcessEntity.collection" );

var  size  =  object . size ();

  the following error message appears:

Cause

The process entity has no data in any attribute (it is not initialized).

Solution

You can define a default value (different from null) in any attribute included within the Process Entity. This can be done executing a rule On Enter of the task

or using default values in any attribute.

 Initializing ONE attribute is enough.