private Node getNode(char[] argString) {
                Node currentNode = root;
 
                for (int i = 0; i < argString.length && currentNode != null; i++) {
                        currentNode = currentNode.getChild(argString[i]);
 
                        if (currentNode == null) {
                                return null;
                        }
                }
 
                return currentNode;
        }