Leetcode 124 Binary Tree Maximum Path Sum

/**
 * Definition for a binary tree node.
 * public class TreeNode {
 *     int val;
 *     TreeNode left;
 *     TreeNode right;
 *     TreeNode() {}
 *     TreeNode(int val) { this.val = val; }
 *     TreeNode(int val, TreeNode left, TreeNode right) {
 *         this.val = val;
 *         this.left = left;
 *         this.right = right;
 *     }
 * }
 */
class Solution {

    public int maxPathSum(TreeNode root){
        if(root.left == null && root.right == null){
            return root.val;
        }
        return maxPathSum2(root).maxV;
    }

    private ReturnWrapper maxPathSum2(TreeNode root) {
        if(root == null){
            return new ReturnWrapper(-2000, -2000, -2000);
        }
        ReturnWrapper rightMaxPath = maxPathSum2(root.right);
        ReturnWrapper leftMaxPath = maxPathSum2(root.left);
        int rootVal = root.val;
        int newEdgeV = Math.max(root.val, root.val + Math.max(rightMaxPath.edgeV, leftMaxPath.edgeV));
        int newSumV = Math.max(Math.max(root.val, root.val + rightMaxPath.edgeV + leftMaxPath.edgeV), root.val + Math.max(rightMaxPath.edgeV, leftMaxPath.edgeV));
        int newMaxV = Math.max(Math.max(newSumV, leftMaxPath.maxV), rightMaxPath.maxV);
        return new ReturnWrapper(newMaxV, newSumV, newEdgeV);
    }

    class ReturnWrapper{
        private int maxV;
        private int sumV;
        private int edgeV;
        public ReturnWrapper(int maxV, int sumV, int edgeV){
            this.maxV = maxV;
            this.sumV = sumV;
            this.edgeV = edgeV;
        }
        public ReturnWrapper(){

        }
        private boolean optimalIncludesRoot(){
            return maxV == sumV;
        }
        private boolean isAnEdge(){
            return sumV == edgeV;
        }
    }
}