public static List<Book> saxReader(InputStream is) {
		try {
			if (spf == null)
			 spf = SAXParserFactory.newInstance();
			SAXParser saxParser = spf.newSAXParser(); 
			XmlContentHandler xmlContentHandler = new XmlContentHandler();
			saxParser.parse(is, xmlContentHandler);
			return xmlContentHandler.getBooks();
		} catch (Exception e) {
			e.printStackTrace();
			return null;
		} finally {
			try {
				is.close();
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
	}