private void removeStudentFromDB(Student student) throws ServerException {
		if (log.isDebugEnabled())
			log.debug("Method call. Arguments: " + student);
		try {
			NodeList groups = document.getElementsByTagName("group");
			Element group = getGroupNodeByNumber(groups,
					student.getGroupNumber());
			if (group == null) {
				ServerException ex = new ServerException(
						"Can not remove student from DB");
				log.error("Exception", ex);
				throw ex;
			}
			Element studentsNode = (Element) group.getElementsByTagName(
					"students").item(0);
			if (studentsNode == null) {
				ServerException ex = new ServerException("Can't remove student");
				log.error("Exception", ex);
				throw ex;
			}
			NodeList students = studentsNode.getChildNodes();
			for (int i = 0; i < students.getLength(); i++) {
				if (students.item(i).getAttributes() != null) {
					if (students.item(i).getAttributes().getNamedItem("id")
							.getNodeValue()
							.equals(new Integer(student.getId()).toString())) {
						studentsNode.removeChild(students.item(i));
						break;
					}
				}
			}
		} catch (DOMException e) {
			ServerException ex = new ServerException("Can't remove student "
					+ student + " from DB", e);
			log.error(ex);
			throw ex;
		}
	}