code: protected void updateTempLines(FeatureTransaction featureTransaction, MouseEvent<?> event) {
  		if (featureTransaction.getNewFeatures() != null && featureTransaction.getNewFeatures().length > 0) {
  			if (tempLine1 == null) {
  				createTempLines(featureTransaction, event);
  			}
  			MultiPolygon multiPolygon = (MultiPolygon) getGeometryIndex().getGeometry(featureTransaction);
  			LinearRing ring = getGeometryIndex().getLinearRing(multiPolygon.getGeometryN(0));
  			if (ring != null) {
  				Coordinate[] coordinates = ring.getCoordinates();
  				if (coordinates != null && coordinates.length > 0) {
  					Coordinate lastCoordinate = coordinates[coordinates.length - 2];
  					LineString lineString1 = featureTransaction.getNewFeatures()[index.getFeatureIndex()].getGeometry()
  							.getGeometryFactory().createLineString(
  									new Coordinate[] {getTransformer().worldToPan(lastCoordinate),
  											getPanPosition(event)});
  					tempLine1.setGeometry(lineString1);
  					mapWidget.render(tempLine1, RenderGroup.VECTOR, RenderStatus.ALL);
  
  					LineString lineString2 = featureTransaction.getNewFeatures()[index.getFeatureIndex()].getGeometry()
  							.getGeometryFactory().createLineString(
  									new Coordinate[] {getTransformer().worldToPan(coordinates[0]),
  											getPanPosition(event)});
  					tempLine2.setGeometry(lineString2);
  					mapWidget.render(tempLine2, RenderGroup.VECTOR, RenderStatus.ALL);
  				}
  			}
  		}
  	}
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