Child Sum Java

// Java program to check children sum property
  
/* A binary tree node has data, pointer to left child 
   and a pointer to right child */
class Node 
{
    int data;
    Node left, right;
  
    public Node(int d) 
    {
        data = d;
        left = right = null;
    }
}
  
class BinaryTree 
{
    Node root;
  
    /* returns 1 if children sum property holds for the given
    node and both of its children*/
    int isSumProperty(Node node) 
    {
          
        /* left_data is left child data and right_data is for right 
           child data*/
        int left_data = 0, right_data = 0;
  
        /* If node is NULL or it's a leaf node then
        return true */
        if (node == null
                || (node.left == null && node.right == null))
            return 1;
        else
        {
             
            /* If left child is not present then 0 is used
               as data of left child */
            if (node.left != null) 
                left_data = node.left.data;
  
            /* If right child is not present then 0 is used
               as data of right child */
            if (node.right != null) 
                right_data = node.right.data;
  
            /* if the node and both of its children satisfy the
               property return 1 else 0*/
            if ((node.data == left_data + right_data)
                    && (isSumProperty(node.left)!=0)
                    && isSumProperty(node.right)!=0)
                return 1;
            else
                return 0;
        }
    }
     
    /* driver program to test the above functions */
    public static void main(String[] args) 
    {
        BinaryTree tree = new BinaryTree();
  
      tree.root = new Node(10);
        tree.root.left = new Node(8);
        tree.root.right = new Node(2);
        tree.root.left.left = new Node(3);
        tree.root.left.right = new Node(5);
        tree.root.right.right = new Node(2);
        if (tree.isSumProperty(tree.root) != 0)
            System.out.println("The given tree satisfies children"
                    + " sum property");
        else
            System.out.println("The given tree does not satisfy children"
                    + " sum property");
    }
}