AvlTree.java

    /**
     * Balances the tree according to the case
     *
     * @param pointer node to balance
     */
    private void balanceTree(Node pointer) {
        int balanceFactor = balanceFactor(pointer);
        if (balanceFactor == HEAVY_LEFT) {
            if (balanceFactor(pointer.getLeft()) == LEFT_THEN_RIGHT) {
                // LR
                rotateLeft(pointer.getLeft());
            }
            // LL
            rotateRight(pointer);
        }

        if (balanceFactor == HEAVY_RIGHT) {
            if (balanceFactor(pointer.getRight()) == RIGHT_THEN_LEFT) {
                // RL
                rotateRight(pointer.getRight());
            }
            // RR
            rotateLeft(pointer);
        }

    }