NotificationsXMLResponse.java

/**
 * Copyright (c) 2010-2016 by the respective copyright holders.
 *
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 */
package org.openhab.binding.rwesmarthome.internal.communicator.xmlresponse;

import java.io.IOException;
import java.io.InputStream;
import java.util.logging.Level;
import java.util.logging.Logger;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;

import org.openhab.binding.rwesmarthome.internal.communicator.exceptions.ConfigurationChangedException;
import org.openhab.binding.rwesmarthome.internal.communicator.exceptions.LogoutNotificationException;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;
import org.xml.sax.SAXException;

/**
 * This class handles the response of the "/update" call, which loads the
 * notifications of RWE Smarthome. Those notifications include e.g. device
 * state changes, configuration changes etc.
 *
 * @author ollie-dev
 *
 */
public class NotificationsXMLResponse extends XMLResponse {

    /**
     * Constructor with input stream.
     * 
     * @param is
     * @throws LogoutNotificationException
     * @throws ConfigurationChangedException
     */
    public NotificationsXMLResponse(InputStream is) throws LogoutNotificationException, ConfigurationChangedException {
        DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();

        try {
            // Using factory get an instance of document builder
            DocumentBuilder db = dbf.newDocumentBuilder();

            // parse using builder to get DOM representation of the XML file
            Document doc = db.parse(is);

            // get the root element
            Element docEle = doc.getDocumentElement();

            // Check for LogoutNotification
            NodeList nl = docEle.getElementsByTagName("LogoutNotification");
            if (nl != null && nl.getLength() > 0) {
                Element el = (Element) nl.item(0);
                String reason = getTextValueFromAttribute(el, "Reason");
                throw new LogoutNotificationException("Logged out from Notifications. Reason:" + reason);
            }

            // Check for ConfigurationChanges
            nl = docEle.getElementsByTagName("ConfigurationChangedNotification");
            if (nl != null && nl.getLength() > 0) {
                Element el = (Element) nl.item(0);
                String configVersion = getTextValueFromAttribute(el, "ConfigurationVersion");
                throw new ConfigurationChangedException("Configuration changed to version " + configVersion);
            }

        } catch (SAXException ex) {
            Logger.getLogger(NotificationsXMLResponse.class.getName()).log(Level.SEVERE, null, ex);
        } catch (IOException ex) {
            Logger.getLogger(NotificationsXMLResponse.class.getName()).log(Level.SEVERE, null, ex);
        } catch (ParserConfigurationException ex) {
            Logger.getLogger(NotificationsXMLResponse.class.getName()).log(Level.SEVERE, null, ex);
        }
    }

}