### Question:
BinaryTree { public void traverseLevelOrder() { if (root == null) { return; } Queue<Node> nodes = new LinkedList<>(); nodes.add(root); while (!nodes.isEmpty()) { Node node = nodes.remove(); System.out.print(" " + node.value); if (node.left != null) { nodes.add(node.left); } if (node.left != null) { nodes.add(node.right); } } }  void add(int value); boolean isEmpty(); int getSize(); boolean containsNode(int value); void delete(int value); void traverseInOrder(Node node); void traversePreOrder(Node node); void traversePostOrder(Node node); void traverseLevelOrder();  }### Answer:
@Test public void givenABinaryTree_WhenTraversingLevelOrder_ThenPrintValues() { BinaryTree bt = createBinaryTree(); bt.traverseLevelOrder(); }