@Reference(cardinality = ReferenceCardinality.MULTIPLE, policy = ReferencePolicy.DYNAMIC)
    protected void setJobExecutionStartCallbackService(IJobExecutionStartCallbackService reference) {
        jobExecutionStartCallbacks.add(reference);
    }
@ Reference ( cardinality = ReferenceCardinality . MULTIPLE , policy = ReferencePolicy . DYNAMIC ) protected void setJobExecutionStartCallbackService ( IJobExecutionStartCallbackService reference ) { jobExecutionStartCallbacks . add ( reference ) ; }
Note the list is not going to have a well-defined order, so it is of limited use.
We probably want to revisit this with some kind of priority/order based on ranking to make
it more useful.

@param reference