code: @Pure
  	public static int getPreferredRoadInternColor() {
  		final Preferences prefs = Preferences.userNodeForPackage(RoadNetworkLayerConstants.class);
  		if (prefs != null) {
  			final String color = prefs.get("ROAD_INTERN_COLOR", null); //$NON-NLS-1$
  			if (color != null) {
  				try {
  					return Integer.valueOf(color);
  				} catch (Throwable exception) {
  					//
  				}
  			}
  		}
  		return DEFAULT_ROAD_INTERN_COLOR;
  	}
docs: Replies the color of the internal data structures used when they
  are drawn on the displayers.
  
  @return the color of the internal data structures, never <code>null</code>.