collect set children model element point time children ad children note children dep modifi function fact primari purpos modifi collect respons make sure call know do param model element element collect children param children children model element param dep set object monitor chang affect list unsupport oper except add support children add isn support dep pointer except children dep cast except children dep reject element illeg argument except children dep reject element collect children object model element list children set dep model element collect current set object children node perspect rule rule rule todo better implement batch event logic group updat tree time entir group synchron access model repositori stai consist queri like requir do updat differ thread event deliveri thread prevent deadlock right protect block collect children collect set children rule children model element invalid element except defin log lp log granular type statement log debug invalid element except explor tree stack trace endif object child children defin log lp log granular type statement lp log local nest statement child log warn perspect rule rule want add explor tree endif defin log lp log granular type express child endif children contain child children add child set depend rule depend model element dep add depend invalid element except defin log lp log granular type statement log debug invalid element except explor tree stack trace endif order children depend need order collect sort children order dep add children 