public void storeDevice(Device d){
  if (!isMaster)   return;
  if (d == null)   return;
  long now=System.nanoTime();
  writeUpdatedDeviceToStorage(d);
  lastWriteTimes.put(d.getDeviceKey(),now);
}

public void storeDevice ( Device d ) { if ( ! isMaster ) return ; if ( d == null ) return ; long now = System . nanoTime ( ) ; writeUpdatedDeviceToStorage ( d ) ; lastWriteTimes . put ( d . getDeviceKey ( ) , now ) ; }
write the given device to storage if we are master . use this method if the device has significantly changed ( e . g . , new ap , new ip , entities removed ) .
