Java Binary Tree InOrder Traversal

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import java.util.Stack;

public class JavaBinaryTreeInorder {

	public static class TreeNode {
		int data;
		TreeNode left;
		TreeNode right;

		TreeNode(int data) {
			this.data = data;
		}
	}

	// Recursive Solution
	public void inOrder(TreeNode root) {
		if (root != null) {
			inOrder(root.left);
			// Visit the node by Printing the node data
			System.out.printf("%d ", root.data);
			inOrder(root.right);
		}
	}

	// Iterative solution
	public void inOrderIter(TreeNode root) {

		if (root == null)
			return;

		Stack<TreeNode> s = new Stack<TreeNode>();
		TreeNode currentNode = root;

		while (!s.empty() || currentNode != null) {

			if (currentNode != null) {
				s.push(currentNode);
				currentNode = currentNode.left;
			} else {
				TreeNode n = s.pop();
				System.out.printf("%d ", n.data);
				currentNode = n.right;
			}
		}
	}

	public static void main(String[] args) {
		JavaBinaryTreeInorder bi = new JavaBinaryTreeInorder();
		// Creating a binary tree
		TreeNode rootNode = createBinaryTree();
		System.out.println("Using Recursive solution:");

		bi.inOrder(rootNode);

		System.out.println();
		System.out.println("-------------------------");
		System.out.println("Using Iterative solution:");

		bi.inOrderIter(rootNode);
	}

	public static TreeNode createBinaryTree() {

		TreeNode rootNode = new TreeNode(40);
		TreeNode node20 = new TreeNode(20);
		TreeNode node10 = new TreeNode(10);
		TreeNode node30 = new TreeNode(30);
		TreeNode node60 = new TreeNode(60);
		TreeNode node50 = new TreeNode(50);
		TreeNode node70 = new TreeNode(70);

		rootNode.left = node20;
		rootNode.right = node60;

		node20.left = node10;
		node20.right = node30;

		node60.left = node50;
		node60.right = node70;

		return rootNode;
	}
}
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