Multiinstance Usertasks

I want to use a multi instance of usertasks which should work like subprocesses
Unfortunately no usertask is created but the whole thing is skipped
To test the process i set a variable of type list with the values 1,2
After that i set the collection variable name of the usertask to the variablename and the elementvariable to a different variablename but the engine just skips the usertask (also if defined the multi instance type to sequential)
I did not find anything in the documentation about this feature…
Can anyone help ?


@bitcasso Your collection variable is probably recognized as empty. So no task instance is created. How do you create your collection variable?

Thanks for your response. I already found the problem.
I have a problem understanding the variable aggregator.
The documentation does not help very much bc it’s confusing to me.
what are all the source and target expressions ?
I want to get sort a map of usertask/output

Have you checked the blog about that topic: Multi Instance Variable Aggregation

The ‘source’ is the variable of one instance, the ‘target’ is the name of the variable in the aggregated variable (created when the multi instance completes).

Yes i have. I needed some time to wrap my head around this. I seems to work with a normal collection but not with a json array. Is there a way to cast a json array to a collection? I had some trouble bc flowable is not able to serialize my objects properly. It fails to serialize primitive types. Workaround was to convert it to a json array but now the flowable engine fails to recognize it as a collection.