CheckBalance.java

private void CheckBalance(Node newNode) {

   if (Math.abs(height(newNode.Left) - height(newNode.Right)) > 1) {//if difference between children's height gre. than 1
            ReBalance(newNode);//rebalance
   }

   if (newNode.Parent == null) return;//if we are on in the root 

   CheckBalance(newNode.Parent);//otherwise, check top levels
}