public Object ResolveArgumentPreviousActor(IActor resolvedActor, String[] parameters, ExecutionContextImpl executionContext)
{
if (parameters.Length != 0)
throw new SystemException("argument previousActor expects exactly zero parameters instead of " + parameters.Length);
IActor actor = executionContext.GetPreviousActor();
if (actor == null)
throw new SystemException("argument previousActor could not be resolve because there is no previous actor");
return actor;
}