More UPnP Programming

Events

Devices contain services
Services have state variables
When a state variable changes state, it can generate events
Control points can subscribe to all event changes in a service
When a control point subscribes, it is sent a lease time. It must renew before this lease time expires
A control point subscribes in CyberGarage using the method ControlPoint.subscribe(Service)
An event is generated by setting the value of a state variable StateVariable.setValue()
The files are available here

Timer

Interface for different implementations of timers, matches the methods defined for the timer service


/**
 * Timer service as per Timer XML description
 * This may be subclassed to provide functionality
 */
package service;

import xmltypes.*;
import org.cybergarage.upnp.Service;

public interface Timer {
 
    public void setTime(Time t);

    public Time getTime();

    public boolean isValidTime();

    // Change start
    public void setService(Service svc);
    // Change end
}

Ticker Timer

Another implementation that runs a "ticker" in a thread to update the time. This timer is invalid until something else sets its time


/**
 * Timer service as per Timer XML description
 *
 * The timer service has two state vbls, Time and TimeValid.
 * Time is continually changing, updated every second. If we kept this
 * state in the cybergarage state vbl (which is a string) then every
 * second we would be parsing the string into a Time object, incrementing
 * it and then turning it back into a string. Kind of wasteful. So it is
 * (maybe) better to keep the state in a Time object (in the Ticker) and 
 * just copy it into the cybergarage state vbl on each change. On the other hand,
 * TimeValid changes rarely and isn't checked much, so we can keep it
 * in the cybergarage state vbl always
 */
package service;

import xmltypes.*;
import org.cybergarage.upnp.Service;
import org.cybergarage.upnp.StateVariable;

public class TickerTimer implements Timer {

    private Ticker ticker;

    // Change start
    private Service service;
    private StateVariable timeVar;
    private StateVariable validVar;
    // Change end

    public TickerTimer() {
    }

    // Change start
    public void setService(Service svc) {
	service = svc;

	Time time = new Time("12:00:00");

	timeVar = svc.getStateVariable("Time");
	timeVar.setValue(time.toString());

	validVar = svc.getStateVariable("TimeValid");
	validVar.setValue("false");
	
	ticker = new Ticker(time, timeVar);
	ticker.start();
    }
    // Change end

    public void setTime(Time t) {
	if (ticker != null) {
	    ticker.stopRunning();
	}

	// Change start
	timeVar.setValue(t.toString());
	validVar.setValue("true");
	// Change end

	ticker = new Ticker(t, timeVar);
	ticker.start();
    }

    public Time getTime() {
	Time time = new Time(timeVar.getValue());
	return time;
    }

    public boolean isValidTime() {
	if (validVar.getValue().equals("true")) {
	    return true;
	} else {
	    return false;
	}
    }
}

class Ticker extends Thread {
    private Time time;
    private boolean keepRunning = true;
    // Change start
    private StateVariable timeVar;
    // Change end

    // Change start
    public Ticker(Time t, StateVariable tVar) {
	time = t;
	timeVar = tVar;
    }
    // Change end

    public void run() {
	while (keepRunning) {
	    try {
		sleep(1000);
	    } catch(InterruptedException e) {
	    }
	    if (keepRunning) {
		time.increment();
		// Change start
		timeVar.setValue(time.toString());
		// Change end
	    }
	}
    }

    public void stopRunning() {
	keepRunning = false;
    }
}

Clock device


/******************************************************************
 *
 *	CyberUPnP for Java
 *
 *	Copyright (C) Satoshi Konno 2002
 *
 *	File : ClockDevice.java
 *
 ******************************************************************/

package device;

import service.*;
import xmltypes.*;

import java.io.*;

import org.cybergarage.upnp.*;
import org.cybergarage.upnp.device.*;
import org.cybergarage.upnp.control.*;
import org.cybergarage.http.*;
import org.cybergarage.upnp.ssdp.*;

public class ClockDevice extends Device implements ActionListener, QueryListener, NotifyListener 
{
    private final static String DESCRIPTION_FILE_NAME = "description/description.xml";
    private final static String PRESENTATION_URI = "clock/presentation";

    private ControlPoint ctrlPoint = new ControlPoint();
    
    private Timer timer;
    private Service timerService;

    private Device lastDeviceSeen;

    public ClockDevice() throws InvalidDescriptionException
    {
	super(new File(DESCRIPTION_FILE_NAME));

	
	UPnP.setEnable(UPnP.USE_ONLY_IPV4_ADDR);

	org.cybergarage.util.Debug.on();

	ctrlPoint.addNotifyListener(this);
	ctrlPoint.start();
	
	Action getTimeAction = getAction("GetTime");
	getTimeAction.setActionListener(this);
	
	Action setTimeAction = getAction("SetTime");
	setTimeAction.setActionListener(this);
	
	Action timeValidAction = getAction("TimeValid");
	timeValidAction.setActionListener(this);
	
	ServiceList serviceList = getServiceList();
	// there should only be a timer service
	timerService = serviceList.getService(0);
	timerService.setQueryListener(this);
	
	setLeaseTime(60);
    }

    public void setTimer(Timer t) {
	timer = t;
	System.out.println("Timer " + timer + " service " + timerService);
	// *****************************************
	// This is the only line that really changed
	// *****************************************
	// Change start
	timer.setService(timerService);
	// Change end
	System.out.println("Our timer service is " + t);
    }
    
    ////////////////////////////////////////////////
    // ActionListener
    ////////////////////////////////////////////////
    
    public boolean actionControlReceived(Action action)
    {
	String actionName = action.getName();
	if (actionName.equals("GetTime") == true) {
	    System.out.println("GetTime action control");

	    Time now = timer.getTime();
	    Argument timeArg = action.getArgument("CurrentTime");
	    timeArg.setValue(now.toString());
	    return true;
	}
	if (actionName.equals("SetTime") == true) {
	    System.out.println("SetTime action control");
	    Argument timeArg = action.getArgument("NewTime");
	    String newTime = timeArg.getValue();
	    timer.setTime(new Time(newTime));
	    System.out.println("SetTime action to " + newTime);
	    return true;
	}
	if (actionName.equals("TimeValid") == true) {
	    System.out.println("TimeValid action control");
	    boolean timeValid = timer.isValidTime();

	    Argument timeArg = action.getArgument("Valid");
	    timeArg.setValue("" + timeValid);
	    return true;
	}
	return false;
    }
    
    ////////////////////////////////////////////////
    // QueryListener
    ////////////////////////////////////////////////

    // Change start    
    public boolean queryControlReceived(StateVariable stateVar)
    {
	System.out.println("query control");
	if (stateVar.getName().equals("Time")) {
	    stateVar.setValue(getTime().toString());
	    return true;
	} else if (stateVar.getName().equals("TimeValid")) {
	    stateVar.setValue("" + isValidTime());
	    return true;
	}
	return false;
    }
    // Change end
    
    ////////////////////////////////////////////////
    // HttpRequestListner
    ////////////////////////////////////////////////

    public void httpRequestRecieved(HTTPRequest httpReq)
    {
	System.out.println("HTTP request: " + httpReq);
	
	String uri = httpReq.getURI();
	if (uri.startsWith(PRESENTATION_URI) == false) {
	    super.httpRequestRecieved(httpReq);
	    return;
	}
    }

    public void setTime(Time time) {
	System.out.println("setTime in clock device to " + time);
	timer.setTime(time);
    }

    public Time getTime() {
	return timer.getTime();
    }

    public boolean isValidTime() {
	return timer.isValidTime();
    }

    public void deviceNotifyReceived(SSDPPacket ssdpPacket) { 

	System.out.println("New SSDPPacket, all " + ssdpPacket);
	/* There doesn;t seem to be a simple way of getting the new
	 * device from the packet, even though CyberLink creates a
	 * new device from it - and adds it to a list. Looks like we
	 * have to get the whole list and search through it for the
	 * device created by this packet :-(
	 */
	DeviceList devList = ctrlPoint.getDeviceList();
	Device dev = null;
	System.out.println("Devices: " + devList.size());
	for (int n = 0; n < devList.size(); n++) {
	    if (devList.getDevice(n).getSSDPPacket() == ssdpPacket) {
		System.out.println("Found the new device matching SSDP packet");
		dev = devList.getDevice(n);
		break;
	    }
	}
	if (dev == null) {
	    // couldn't find it? That shouldn't happen...
	    return;
	}

	ServiceList timerServices = new ServiceList();

	if (dev.getDeviceType().equals("urn:schemas-upnp-org:device:clock:1")) {
	    ServiceList services = dev.getServiceList();
	    for (int m = 0; m < services.size(); m++) {
		Service svc = services.getService(m);
		if (svc.getServiceType().equals("urn:schemas-upnp-org:service:timer:1")) {
		    timerServices.add(svc);
		}
	    }
	}

	tryClockValidation(timerServices);
    } 

    private ServiceList getTimerServices() {
	ServiceList timerServices = new ServiceList();

	DeviceList devList = ctrlPoint.getDeviceList();
	System.out.println("Devices: " + devList.size());
	for (int n = 0; n < devList.size(); n++) {
	    Device dev = devList.getDevice(n);
	    if (dev.getDeviceType().equals("urn:schemas-upnp-org:device:clock:1")) {
		ServiceList services = dev.getServiceList();
		for (int m = 0; m < services.size(); m++) {
		    Service svc = services.getService(m);
		    if (svc.getServiceType().equals("urn:schemas-upnp-org:service:timer:1")) {
			timerServices.add(svc);
		    }
		}
	    }
	}
	return timerServices;
    }

    private void tryClockValidation(ServiceList services) {
	org.cybergarage.util.Debug.on();
	for (int n = 0; n < services.size(); n++) {
	    Service svc = (Service) services.elementAt(n);

	    System.out.println("Checking service " + svc);
	    Action validAction = svc.getAction("TimeValid");
	    if (validAction.postControlAction()) {
		System.out.println("Checking TimeValid succeeded");
		Argument arg = validAction.getArgument("Valid");
		String value = arg.getValue();
		System.out.println("valid time? " + value);
		if (isValidTime() && value.equals("false")) {
		    // other clock needs to be set
		    Action setTimeAction = svc.getAction("SetTime");
		    setTimeAction.setArgumentValue("NewTime",
						    getTime().toString());
		    setTimeAction.postControlAction();
		} else if (! isValidTime() && value.equals("true")) {
		    Action getTimeAction = svc.getAction("GetTime");
		    if ( ! getTimeAction.postControlAction()) {
			System.out.println("GetTime post action failed");
		    }

		    Argument arg2 = getTimeAction.getArgument("CurrentTime");
		    Object val = arg2.getValue();
		    System.out.println("Arg type " +  val.getClass());
		    System.out.println("setTime in clock validation to " + arg2.getValue());
		    setTime(new Time(arg2.getValue()));
		}
	    }
	}
    }
}

Listener

This will listen to events and print them


/**
 * Listen for state changes in clocks
 */

package client;

import service.*;
import xmltypes.*;

import java.io.*;

import org.cybergarage.upnp.*;
import org.cybergarage.upnp.device.*;
import org.cybergarage.upnp.control.*;
import org.cybergarage.http.*;
import org.cybergarage.upnp.ssdp.*;
import org.cybergarage.upnp.event.*;

public class ValidityListener implements EventListener, NotifyListener 
{
    private ControlPoint ctrlPoint = new ControlPoint();
    
    private StateVariable timeVar;
    private Device lastDeviceSeen;

    public static void main(String[] args) {
	ValidityListener client = new ValidityListener();
	
	Object keepAlive = new Object();
	synchronized(keepAlive) {
	    try {
		// Wait for a "notify" from another thread
		// that will never be sent.
		// So we stay alive for ever
		keepAlive.wait();
	    } catch(java.lang.InterruptedException e) {
		// do nothing
	    }
	}
    }

    public ValidityListener()
    {
	UPnP.setEnable(UPnP.USE_ONLY_IPV4_ADDR);

	// org.cybergarage.util.Debug.on();

	ctrlPoint.addNotifyListener(this);

	// Change start
	ctrlPoint.addEventListener(this);
	// Change end

	ctrlPoint.start();
    }

    // Change start
    public void eventNotifyReceived(String uuid, long seq, 
				    String varName, String value) {
	// a new event has arrived
	System.out.println("UUID: \"" +  uuid + "\"");
	System.out.println("Name: \"" +  varName + "\"");
	System.out.println("Value: \"" +  value + "\"");
    }
    // Change end

    public void deviceNotifyReceived(SSDPPacket ssdpPacket) { 
	DeviceList devList = ctrlPoint.getDeviceList();
	Device dev = null;
	System.out.println("Devices: " + devList.size());
	for (int n = 0; n < devList.size(); n++) {
	    if (devList.getDevice(n).getSSDPPacket() == ssdpPacket) {
		System.out.println("Found the new device matching SSDP packet");
		dev = devList.getDevice(n);
		break;
	    }
	}
	if (dev == null) {
	    // couldn't find it? That shouldn't happen...
	    return;
	}

	if (dev.getDeviceType().equals("urn:schemas-upnp-org:device:clock:1")) {
	    ServiceList services = dev.getServiceList();
	    for (int m = 0; m < services.size(); m++) {
		Service svc = services.getService(m);
		if (svc.getServiceType().equals("urn:schemas-upnp-org:service:timer:1")) {
		    System.out.println("Subscribing to timer events");

		    // Change start
		    // subscribe to events
		    ctrlPoint.subscribe(svc);
		    // Change end
		}
	    }
	}
    } 
}

Compile and run

Compile all files using javac with classpath set to include
- src directory
- clink132a.jar
- xercesImpl.jar
- xml-apis.jar
Run the files using java with classpath set to
- classes directory
- clink132a.jar
- xercesImpl.jar
- xml-apis.jar

The run commands are


      java clock.TickerClock


      java clock.ComputerClock


      java client.ValidityListener

Remote UI

The "local" UI for a clock is the frame that shows it ticking and maybe flashing
Each clock is aware of the other clocks and makes programmatic calls on it, but does not display the other clocks, only itself
The validity program makes programmatic calls on the clocks, but does not display any of them
If a control point displays a UI for a clock then it has two choices
- display a general UI for a clock, no matter what type
- display a UI customised for each clock (e.g. different colours, different layout, banner ads, etc)
If a control point needs to display a clock's UI, then it must get it from the clock

UPnP remote UI

UPnP standardises on an HTML document for a device's remote UI
The device XML description may contain a URL for the UI document
It is unspecified what the HTML document can do. HTMl form? Javascript?
It is unspecified how the browser then interacts with the device

Cybergarage remote UI

A device runs an HTTP server (to handle SOAP requests)
This is done by a method Device.httpRequestRecieved() (note the spelling mistake)
Your device (which inherits from Device) can override this method by looking for HTTP requests relating to UI,and passing all others to its super-class
On the client side, the JEditorPane can display HTML pages loaded through a URL
It will respond to mouse clicks over a hyperlink if isEditable() is set to false, and then calls a HyperLinkListener
The method hyperLinkUpdate() can load or reload a URL, but the code is a bit messy due to a caching bug in JEditorPane
I haven't figured out yet how to monitor a Submit button in a page - perhaps you need to get the DOM and attach listeners in there
The files are available here

Remote UI ClockDevice


/******************************************************************
 *
 *	CyberUPnP for Java
 *
 *	Copyright (C) Satoshi Konno 2002
 *
 *	File : ClockDevice.java
 *
 ******************************************************************/

package device;

import service.*;
import xmltypes.*;

import java.io.*;

import org.cybergarage.upnp.*;
import org.cybergarage.upnp.device.*;
import org.cybergarage.upnp.control.*;
import org.cybergarage.http.*;
import org.cybergarage.upnp.ssdp.*;

public class ClockDevice extends Device implements ActionListener, QueryListener, NotifyListener 
{
    private final static String DESCRIPTION_FILE_NAME = "description/description.xml";
    // Change start
    private final static String PRESENTATION_URI = "/presentation";
    private final static String REFRESH_UI = "/refresh";
    // Change end

    private ControlPoint ctrlPoint = new ControlPoint();
    
    private Timer timer;
    private Service timerService;

    private Device lastDeviceSeen;

    public ClockDevice() throws InvalidDescriptionException
    {
	super(new File(DESCRIPTION_FILE_NAME));

	UPnP.setEnable(UPnP.USE_ONLY_IPV4_ADDR);

	org.cybergarage.util.Debug.on();

	ctrlPoint.addNotifyListener(this);
	ctrlPoint.start();
	
	Action getTimeAction = getAction("GetTime");
	getTimeAction.setActionListener(this);
	
	Action setTimeAction = getAction("SetTime");
	setTimeAction.setActionListener(this);
	
	Action timeValidAction = getAction("TimeValid");
	timeValidAction.setActionListener(this);
	
	ServiceList serviceList = getServiceList();
	// there should only be a timer service
	timerService = serviceList.getService(0);
	timerService.setQueryListener(this);
	
	setLeaseTime(60);
    }

    public void setTimer(Timer t) {
	timer = t;
	System.out.println("Our timer service is " + t);
    }
    
    ////////////////////////////////////////////////
    // ActionListener
    ////////////////////////////////////////////////
    
    public boolean actionControlReceived(Action action)
    {
	String actionName = action.getName();
	if (actionName.equals("GetTime") == true) {
	    System.out.println("GetTime action control");

	    Time now = timer.getTime();
	    Argument timeArg = action.getArgument("CurrentTime");
	    timeArg.setValue(now.toString());
	    return true;
	}
	if (actionName.equals("SetTime") == true) {
	    System.out.println("SetTime action control");
	    Argument timeArg = action.getArgument("NewTime");
	    String newTime = timeArg.getValue();
	    timer.setTime(new Time(newTime));
	    System.out.println("SetTime action to " + newTime);
	    return true;
	}
	if (actionName.equals("TimeValid") == true) {
	    System.out.println("TimeValid action control");
	    boolean timeValid = timer.isValidTime();

	    Argument timeArg = action.getArgument("Valid");
	    timeArg.setValue("" + timeValid);
	    return true;
	}
	return false;
    }
    
    ////////////////////////////////////////////////
    // QueryListener
    ////////////////////////////////////////////////
    
    public boolean queryControlReceived(StateVariable stateVar)
    {
	System.out.println("query control");
	if (stateVar.getName().equals("Time")) {
	    stateVar.setValue(getTime().toString());
	    return true;
	} else if (stateVar.getName().equals("TimeValid")) {
	    stateVar.setValue("" + isValidTime());
	    return true;
	}
	return false;
    }
    
    //
    // HttpRequestListner
    //
    // This is responsible for generating the HTML UI
    //

    public void httpRequestRecieved(HTTPRequest httpReq)
    {
	System.out.println("HTTP request: " + httpReq);
	
	String uri = httpReq.getURI();

	// Change start
	if (uri.startsWith(PRESENTATION_URI)) {
	    sendPage(httpReq);
	} else if (uri.startsWith(REFRESH_UI)) {
	    sendPage(httpReq);
	} else {
	    super.httpRequestRecieved(httpReq);
	    return;
	}
	// Change end
    }

    // Change start
    private void sendPage(HTTPRequest httpReq) {
	// deliver an HTML page
	String time = getTime().toString();
	String refreshUrl = "http://" +
	    httpReq.getLocalAddress() + 
	    ":" +
	    httpReq.getLocalPort() +
	    REFRESH_UI;
	System.out.println("referesh url " + refreshUrl);

	// the page attempts to turn caching off at the client side
	// but a bug in JEditorPane ignores the Cache-Control value
	String page = "<html>\n" + 
	    "<head>\n" +
	    "</head>\n" +
	    "<body>\n" +
	    "<form method=\"post\" action=\"" + 
	    refreshUrl + "\">\n" +
	    "New time" +
	    "<input type=\"text\" name=\"time\">\n" +
	    "<input type=\"submit\">\n" +
	    "<p>\n" +  
	    time + 
	    "\n<br>\n" +
	    "<a href=\"" +
	    refreshUrl +
	    "\"> Refresh </a>\n" +
	    "</p>\n" +
	    "</body>\n" +
	    "</html>\n";
	
        System.out.println("Sending page " + page);
	HTTPResponse response = new HTTPResponse();
	response.setStatusCode(HTTPStatus.OK);
	response.setContent(page);
	response.setCacheControl(0); // no caching - ignored by JEditorPane
	httpReq.post(response);
    }
    // Change end

    public void setTime(Time time) {
	System.out.println("setTime in clock device to " + time);
	timer.setTime(time);
    }

    public Time getTime() {
	return timer.getTime();
    }

    public boolean isValidTime() {
	return timer.isValidTime();
    }

    public void deviceNotifyReceived(SSDPPacket ssdpPacket) { 

	System.out.println("New SSDPPacket, all " + ssdpPacket);
	/* There doesn;t seem to be a simple way of getting the new
	 * device from the packet, even though CyberLink creates a
	 * new device from it - and adds it to a list. Looks like we
	 * have to get the whole list and search through it for the
	 * device created by this packet :-(
	 */
	DeviceList devList = ctrlPoint.getDeviceList();
	Device dev = null;
	System.out.println("Devices: " + devList.size());
	for (int n = 0; n < devList.size(); n++) {
	    if (devList.getDevice(n).getSSDPPacket() == ssdpPacket) {
		dev = devList.getDevice(n);
		break;
	    }
	}
	if (dev == null) {
	    // couldn't find it? That shouldn't happen...
	    return;
	}

	/* this doesn't work :-( device changes each time
	
	if (dev == lastDeviceSeen) {
	    // UPnP sends repeat messages to try to make sure things
	    // get through. But we don't want to repeat work
	    System.out.println("Seen this device before");
	    lastDeviceSeen = dev;
	    return;
	}
	*/

	ServiceList timerServices = new ServiceList();

	if (dev.getDeviceType().equals("urn:schemas-upnp-org:device:clock:1")) {
	    ServiceList services = dev.getServiceList();
	    for (int m = 0; m < services.size(); m++) {
		Service svc = services.getService(m);
		if (svc.getServiceType().equals("urn:schemas-upnp-org:service:timer:1")) {
		    timerServices.add(svc);
		}
	    }
	}

	tryClockValidation(timerServices);
    } 

    private ServiceList getTimerServices() {
	ServiceList timerServices = new ServiceList();

	DeviceList devList = ctrlPoint.getDeviceList();
	System.out.println("Devices: " + devList.size());
	for (int n = 0; n < devList.size(); n++) {
	    Device dev = devList.getDevice(n);
	    if (dev.getDeviceType().equals("urn:schemas-upnp-org:device:clock:1")) {
		ServiceList services = dev.getServiceList();
		for (int m = 0; m < services.size(); m++) {
		    Service svc = services.getService(m);
		    if (svc.getServiceType().equals("urn:schemas-upnp-org:service:timer:1")) {
			timerServices.add(svc);
		    }
		}
	    }
	}
	return timerServices;
    }

    private void tryClockValidation(ServiceList services) {
	org.cybergarage.util.Debug.on();
	for (int n = 0; n < services.size(); n++) {
	    Service svc = (Service) services.elementAt(n);

	    System.out.println("Checking service " + svc);
	    Action validAction = svc.getAction("TimeValid");
	    if (validAction.postControlAction()) {
		System.out.println("Checking TimeValid succeeded");
		Argument arg = validAction.getArgument("Valid");
		String value = arg.getValue();
		System.out.println("valid time? " + value);
		if (isValidTime() && value.equals("false")) {
		    // other clock needs to be set
		    Action setTimeAction = svc.getAction("SetTime");
		    setTimeAction.setArgumentValue("NewTime",
						    getTime().toString());
		    setTimeAction.postControlAction();
		} else if (! isValidTime() && value.equals("true")) {

		    Action getTimeAction = svc.getAction("GetTime");
		    if ( ! getTimeAction.postControlAction()) {
			System.out.println("GetTime post action failed");
		    }
		
		    Argument arg2 = getTimeAction.getArgument("CurrentTime");
		    Object val = arg2.getValue();
		    System.out.println("Arg type " +  val.getClass());
		    System.out.println("setTime in clock validation to " + arg2.getValue());
		    setTime(new Time(arg2.getValue()));
		}
	    }
	}
    }
}

Remote UI client


/**
 * Listen for state changes in clocks
 */

package client;

import service.*;
import xmltypes.*;

import java.io.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.text.Document;
import java.awt.*;

import org.cybergarage.upnp.*;
import org.cybergarage.upnp.device.*;
import org.cybergarage.upnp.control.*;
import org.cybergarage.http.*;
import org.cybergarage.upnp.ssdp.*;
import org.cybergarage.upnp.event.*;

import java.net.URL;
import java.net.HttpURLConnection;

public class UI extends JFrame implements EventListener, NotifyListener 
{
    private ControlPoint ctrlPoint = new ControlPoint();
    private DeviceList knownDevices = new DeviceList();
    private StateVariable timeVar;

    private FlowLayout layout = new FlowLayout();
    private Container contentPane = getContentPane();

    public static void main(String[] args) {
	UI client = new UI();
    }

    public UI()
    {
	UPnP.setEnable(UPnP.USE_ONLY_IPV4_ADDR);

	org.cybergarage.util.Debug.on();

	ctrlPoint.addNotifyListener(this);
	ctrlPoint.addEventListener(this);
	ctrlPoint.start();

	contentPane.setLayout(layout);
	setSize(200, 200);
	setVisible(true);
    }

    public void eventNotifyReceived(String uuid, long seq, 
				    String varName, String value) {
	System.out.println("UUID: \"" +  uuid + "\"");
	System.out.println("Name: \"" +  varName + "\"");
	System.out.println("Value: \"" +  value + "\"");
    }


    public void deviceNotifyReceived(SSDPPacket ssdpPacket) { 
	if ( ! ssdpPacket.getNTS().equals("ssdp:alive")) {
	    return;
	}

	/* This code cleaned up to avoid repeating
	 * service finds, but no changes of relevance
	 * to UI
	 */

	/* We can get multiple packets for one device from multiple
	 * UDP packets sent in case one is lost. Also, we get
	 * rebroadcasts every few minutes. This is tedious
	 */

	Device dev = getDeviceFromPacket(ssdpPacket);
	if (dev == null) {
	    // This can happen if the packet describes a service, 
	    // a device, but not a ROOT device
	    return;
	}

	// process the packet if it is for a new device
	if (isNewDevice(dev)) {
	    if (dev.getDeviceType().equals("urn:schemas-upnp-org:device:clock:1")) {
		// Change start
		// The presentation URL is relative e.g. /presentation
		String presentationURL = dev.getPresentationURL();
		System.out.println("Presentation url is \"" + 
				   presentationURL + "\"");
		// the URLBase is the http://hostname
		String urlBase = dev.getURLBase();
		System.out.println("Adding new device " + dev);
		System.out.println("From packet " + ssdpPacket);
		addClock(/* urlBase + */ presentationURL);
		// Change end
	    }
	} else {
	    System.out.println("Seen this device before " + dev);
	}
    } 

    /* New code, just cleans up old stuff
     * No changes for UI
     */
    private Device getDeviceFromPacket(SSDPPacket packet) {
	DeviceList devList = ctrlPoint.getDeviceList();
	for (int n = 0; n < devList.size(); n++) {
	    Device dev = devList.getDevice(n);
	    if (dev.getSSDPPacket() == packet) {
		return dev;
	    }
	}
	// this will happen for services/embedded devices etc
	System.out.println("No device found for packet " + packet);
	return null;
    }

    /* New code, just cleans up old stuff
     * No changes for UI
     */
    private boolean isNewDevice(Device dev) {
	System.out.println("UDN " + dev.getUDN());

	for (int n = 0; n < knownDevices.size(); n++) {
	    if (dev.getUDN().equals(knownDevices.getDevice(n).getUDN())) {
		return false;
	    }
	}
	knownDevices.add(dev);
	return true;
    }

    // Change start has to get UI from device and display it
    // Display is done here in a JEditPane
    private void addClock(String url) {
	// get HTML page from URL, put it in a component and add it to this
	System.out.println("URL is " + url);

	/* OR: use Runtime.exec() to start IE,Netscape, etc
	 * and pass it the URL
	 */

	/* JEditorPane DOES handle forms properly after all!
	 */
	final JEditorPane pane = new JEditorPane();
	try {
	    pane.setPage(url);
	    pane.setEditable(false); // or we can't follow hyperlinks
	    System.out.println("New page contents " + pane.getText());
	    contentPane.add(pane);
	} catch(IOException e) {
	    e.printStackTrace();
	}

	// listen for hyperlink events
	pane.addHyperlinkListener(new HyperlinkListener() {
	        // user over/clicking Refresh hyperlink
		public void hyperlinkUpdate(HyperlinkEvent e) {
		    java.net.URL url = e.getURL();

		    // Turn caching off! 
		    // Due to a bug in  JEditorPane, this doesn't work
		    HttpURLConnection uc = null;
		    try {
			uc = (HttpURLConnection)url.openConnection();
		    } catch(IOException ioe) {
			ioe.printStackTrace();
			return;
		    }
		    uc.setUseCaches(false);

		    if (e.getEventType() == HyperlinkEvent.EventType.ACTIVATED) {
			try {
			    // url was clicked on - we should reload the page

			    // WORKAROUND for JEditorPane bug always caching
			    // url even if it's contents have changed, or
			    // Expires has happened or Cache-Control set to
			    // "no-cache", etc
			    // Clear the internal URL object in this control
			    // TO PREVENT URL CACHING...
			    Document doc = pane.getDocument();
			    doc.putProperty(Document.StreamDescriptionProperty,null);
			    // Sun know of this bug, and just promise to fix the doco :-(

			    // now reload it
			    pane.setPage(url);
			} catch(IOException ioe) {
			    ioe.printStackTrace();
			}
		    }
		}
	    }
	 );
    }
    // Change end
}

Compile and run

Compile all files using javac with classpath set to include
- src directory
- clink132a.jar
- xercesImpl.jar
- xml-apis.jar
Run the files using java with classpath set to
- classes directory
- clink132a.jar
- xercesImpl.jar
- xml-apis.jar

The run commands are


      java clock.TickerClock


      java clock.ComputerClock


      java client.UI

Jan Newmarch (http://jan.newmarch.name)

This work is licensed under a Creative Commons License
The moral right of Jan Newmarch to be identified as the author of this page has been asserted.