@Override
	public List<String> read() {
		
		List<String> expList = new ArrayList<String>();

		try {

			File xmlFile = new File("C:\\calcXmlFiles\\calc.xml");
			DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
			DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();
			Document doc = dBuilder.parse(xmlFile);
			
			NodeList nList = doc.getElementsByTagName("expression");		
			
			for (int i = 0; i < nList.getLength(); i++) {
				expList.add(nList.item(i).getTextContent());				
			}			

		} catch (ParserConfigurationException e) {
			e.printStackTrace();
		} catch (SAXException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}
		
		return expList;

	}