### Question:
ConnectableNode { public boolean contains(Node node) { return nodes.contains(node); } ConnectableNode(Node... nodes);  ConnectableNode(Collection<Node> nodes); boolean isConnectable(ConnectableNode node); boolean contains(Node node); int size(); Iterator<Node> getNodesIterator();  }### Answer:
@Test public void testContains() throws Exception { ConnectableNode node1 = new ConnectableNode(TestUtils.getNode(1), TestUtils.getNode(2)); assertTrue(node1.contains(TestUtils.getNode(1))); assertTrue(node1.contains(TestUtils.getNode(2))); assertFalse(node1.contains(TestUtils.getNode(3))); ConnectableNode node2 = new ConnectableNode(TestUtils.asNodes(1, 2, 3, 4)); assertTrue(node2.contains(TestUtils.getNode(1))); assertTrue(node2.contains(TestUtils.getNode(2))); assertTrue(node2.contains(TestUtils.getNode(3))); assertTrue(node2.contains(TestUtils.getNode(4))); assertFalse(node2.contains(TestUtils.getNode(5))); }