Balanced Binary Tree

public class Solution {
    public boolean isBalanced(TreeNode root) {
        if (root==null) return true;
        if(Math.abs(maxDepth(root.right)-maxDepth(root.left))>1) return false;
        return isBalanced(root.left)&& isBalanced(root.right);
    }
    public int maxDepth(TreeNode root) {
        if(root==null) return 0;
        return(1+ Math.max(maxDepth(root.left),maxDepth(root.right)));
    }
}