class MutualEdgeFilter extends AbstractFilter implements EdgeFilter {

        public MutualEdgeFilter() {
            super(NbBundle.getMessage(MutualEdgeBuilder.class, "MutualEdgeBuilder.name"));
        }

        @Override
        public boolean init(Graph graph) {
            return !graph.isUndirected();
        }

        @Override
        public boolean evaluate(Graph graph, Edge edge) {<FILL_FUNCTION_BODY>}

        @Override
        public void finish() {
        }
    }

            if (edge.isDirected()) {
                DirectedGraph directedGraph = (DirectedGraph) graph;
                return directedGraph.getMutualEdge(edge) != null;
            }
            return false;
        
<no_super_class>