org.deepsymmetry.beatlink

Class DeviceListener

java.lang.Object

org.deepsymmetry.beatlink.DeviceListener

public class DeviceListener
extends Object

Watches for devices to report their presence by broadcasting keep-alive packets on port 50000, and keeps a list of the devices that have been seen, as well as the network interface and interface address on which they were seen.

Field Summary

Fields

Modifier and Type	Field and Description
static int	ANNOUNCEMENT_PORT The port on which devices send keep-alive messages to report their presence on the network.
static int	MAXIMUM_AGE The number of milliseconds after which we will consider a device to have disappeared if we have not received an announcement from it.

Method Summary

Modifier and Type	Method and Description
static List<DeviceAnnouncement>	currentDevices() Get the list of devices which currently can be seen on the network.
static boolean	isActive() Check whether we are presently listening for device announcements.
static void	start() Start listening for device announcements and keeping track of the DJ Link devices visible on the network.
static void	stop() Stop listening for device announcements.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

ANNOUNCEMENT_PORT

public static final int ANNOUNCEMENT_PORT

The port on which devices send keep-alive messages to report their presence on the network.

See Also:

Constant Field Values

MAXIMUM_AGE

public static final int MAXIMUM_AGE

The number of milliseconds after which we will consider a device to have disappeared if we have not received an announcement from it.

See Also:

Constant Field Values

Method Detail

isActive

public static boolean isActive()

Check whether we are presently listening for device announcements.

Returns:

true if our socket is open and monitoring for DJ Link devices announcements on the network.

start

public static void start()
                  throws SocketException

Start listening for device announcements and keeping track of the DJ Link devices visible on the network. If already listening, has no effect.

Throws:

SocketException - if the socket to listen on port 50000 cannot be created.

stop

public static void stop()

Stop listening for device announcements. Also discards any announcements which had been received.

currentDevices

public static List<DeviceAnnouncement> currentDevices()

Get the list of devices which currently can be seen on the network.

Returns:

the DJ Link devices which have been heard from recently enough to be considered active.