Node node2 = factory.newNode();
Node node3 = factory.newNode();
Node node4 = factory.newNode();
Node node5 = factory.newNode();
Node node6 = factory.newNode();
graph.addNode(node1);
graph.addNode(node4);
graph.addNode(node2, node1);
graph.addNode(node3, node1);
graph.addNode(node5, node4);
graph.addNode(node6);