Prints a tree very pretty

PrintATree.java

/* Strongly Inspired By
 * http://stackoverflow.com/questions/4965335/how-to-print-binary-tree-diagram
 */
	
	public void fancyPrint(){
		int maxLevel = maxHeight(root);
		nodePrinter(Collections.singletonList(root), 1, maxLevel);
	}

	private void nodePrinter(List<Node<E>> nodes, int level, int maxLevel){
		if(nodes.isEmpty() || allNull(nodes))
			return;
		int floor = maxLevel - level;
		int edgeLines = (int) Math.pow(2, (Math.max(floor - 1, 0)));
		int firstSpaces = (int) Math.pow(2, (floor)) - 1;
		int betweenSpaces = (int) Math.pow(2, (floor + 1)) - 1;

		for (int i = 0; i < firstSpaces; i++) System.out.print(" ");

		List<Node<E>> newNodes = new ArrayList<Node<E>>();
		for (Node<E> node : nodes) {
	    		if (node != null) {
				System.out.print(node.element);
				newNodes.add(node.left);
				newNodes.add(node.right);
			} else {
				newNodes.add(null);
				newNodes.add(null);
				System.out.print(" ");
			}
			for (int i = 0; i < betweenSpaces; i++) System.out.print(" ");
		}
		System.out.println("");

		for(int i=1; i <= edgeLines; i++) {
			for(int j=0; j < nodes.size(); j++) {
				for (int k = 0; k < firstSpaces - i + 1; k++) System.out.print(" ");
				if(nodes.get(j) == null) {
					for (int k = 0; k < edgeLines * 2 + i + 1; k++) System.out.print(" ");
					continue;
				}
				
				if(nodes.get(j).hasLeft())
					System.out.print("/");
				else
					System.out.print(" ");

				for (int k = 0; k < 2 * i - 1; k++) System.out.print(" ");

				if(nodes.get(j).hasRight())
					System.out.print("\\");
				else
					System.out.print(" ");

				for (int k = 0; k < edgeLines + edgeLines - i; k++) System.out.print(" ");

			}

			System.out.println("");
		}
		nodePrinter(newNodes, level+1, maxLevel);
	}

	private static <E> boolean allNull(List<E> list) {
		for (Object object : list) {
			if (object != null)
				return false;
        	}

        	return true;
	}
	
	private int maxHeight(Node<E> currentNode) {
		if (currentNode == null)
			return 0;

		int leftSubtreeHeight = maxHeight(currentNode.left) + 1;
		int rightSubtreeHeight = maxHeight(currentNode.right) + 1;
		return (rightSubtreeHeight > leftSubtreeHeight ? rightSubtreeHeight : leftSubtreeHeight);
	}