Add() {         DirectedMultigraph<String> g = new DirectedMultigraph<String>();         Set<DirectedTypedEdge<String>> edges = g.edges();         assertEquals(g.size(), edges.size());         edges.add(new SimpleDirectedTypedEdge<String>("type-0",0, 0));         assertEquals(0, g.order());         assertEquals(0, g.size());         assertEquals(0, edges.size());         assertTrue(g.contains(new SimpleDirectedTypedEdge<String>("type-0",0, 0)));         assertTrue(edges.contains(new SimpleDirectedTypedEdge<String>("type-0",0, 0)));     }      @Test public void testEdgeViewRemove() {         DirectedMultigraph<String> g = new DirectedMultigraph<String>();         Set<DirectedTypedEdge<String>> edges = g.edges();         assertEquals(g.size(), edges.size());         edges.add(new SimpleDirectedTypedEdge<String>("type-0",0, 0));         