I've done the test and the result is there isnt any concurrent processing.
jbpm IS NOT a threading system...(discussed lots of times) if you want concurrent processing, use async actions that are processesed e.g. using jms.... That way the loop is real quick and processing 'concurrent'
the effect of this is that first one path of execution is traversed till it reaches the join node and then the other. There isnt any concurrent processing.
I think the next transition is also invoked when another transition path gets into some wait state, such as a task node. If, in the websale example, you change the "ship item" node into some task node then two tasks are created, and you can choose in which order to execute those.
correct, until it reaches the join or a waitstate.