code: static void checkErrors( Collection<RoboconfError> errors, Logger logger )
  	throws InvalidApplicationException {
  
  		if( RoboconfErrorHelpers.containsCriticalErrors( errors ))
  			throw new InvalidApplicationException( errors );
  
  		// Null language => English (right language for logs)
  		Collection<RoboconfError> warnings = RoboconfErrorHelpers.findWarnings( errors );
  		for( String warningMsg : RoboconfErrorHelpers.formatErrors( warnings, null, true ).values())
  			logger.warning( warningMsg );
  	}
docs: A method to check errors.
  @param errors a non-null list of errors
  @param logger a logger
  @throws InvalidApplicationException if there are critical errors