Maximum depth of left node in Binary Tree

Given a Binary tree, print the maximum depth of a left node.( the node needs to be a left child ) (if the node is right child of the left child of the root node then it wont count as a left node)

import java.io.*;
class Node
{
    int data;
    Node left,right;
    Node(int data)
    {
        this.data=data;
        left=right=null;
    }
}
class TreeQuestion {
    Node root;
    static int max=0;
    void maxDepth(Node root,int direction,int depth)
    {
        if(root==null)
          return;
        if(direction==1)
        {
            max=Math.max(max,depth);
        }
        maxDepth(root.left,1,depth+1);
        maxDepth(root.right,2,depth+1);
    }
    public static void main (String[] args) {
        TreeQuestion tree=new TreeQuestion();
        tree.root=new Node(1);
        tree.root.left=new Node(2);
        tree.root.left.left=new Node(3);
        tree.root.left.left.left=new Node(4);
        tree.maxDepth(tree.root,1,0);
        System.out.println(max+1);
       
    }
}