class ExtSourceXML extends ExtSource implements ExtSourceApi {

	@Override
	public List<Map<String, String>> getUsersSubjects() {
		// Get the query for the users subjects
		String queryForUsers = getAttributes().get(UsersManager.USERS_QUERY);

		//If there is no query for users, throw exception
		if(queryForUsers == null) throw new InternalErrorException("usersQuery can't be null");

		//Get file or uri of xml
		prepareEnvironment();

		return xpathParsing(queryForUsers, 0);
	}

}