Hello Please i m using the class linegraphbuilder to build a graph from a shapefile. this is the code i used: LineGraphBuilder lgb = new LineGraphBuilder(); FeatureSource fs = this.frame.mapPane.getMapContext().getLayer(0).getFeatureSource(); FeatureResults fr = fs.getFeatures(); FeatureCollection fc = fr.collection(); FeatureIterator f = fc.features(); //envelope - The bounding box that encloses the unvalidated data Envelope envelope = fc.getBounds(); while (f.hasNext()) { Feature ft = f.next(); if (envelope.contains(ft.getBounds())) { lgb.add(ft); } } org.geotools.graph.Graph g = lgb.build(); but what i read in the documentation is that add() function work with feature with linestring geometry, however the feature that are extracted from the shapefile are of type MultilineString So is there a way to solve this problem or i can not use at all the class linegraphbuilder thanks in advance