question: get the instance of piminterfaces . create the instance if needed . concode_field_sep NetworkConfigService configService concode_elem_sep Map<ConnectPoint,PIMInterface> interfaces concode_elem_sep Timeout helloTimer concode_elem_sep InternalConfigListener configListener concode_elem_sep PIMInterfaces instance concode_elem_sep int helloMessageInterval concode_elem_sep InterfaceService interfaceService concode_elem_sep Logger log concode_field_sep PIMInterface getInterface concode_elem_sep void startHelloTimer concode_elem_sep void removeInterface concode_elem_sep void removeInterface concode_elem_sep PIMInterface addInterface concode_elem_sep void initInterfaces concode_elem_sep void updateInterfaces concode_elem_sep String printInterfaces concode_elem_sep Collection<PIMInterface> getInterfaces concode_elem_sep void run concode_elem_sep void initialize concode_elem_sep void event
target: PIMInterfaces function ( ) { if ( null == instance ) { instance = new PIMInterfaces ( ) ; } return instance ; }