java.net

Class MulticastSocket

java.lang.Object

java.net.DatagramSocket

java.net.MulticastSocket

All Implemented Interfaces:

Closeable, AutoCloseable

public class MulticastSocket
extends DatagramSocket

This class implements a multicast socket for sending and receiving IP multicast datagram packets.

See Also:

DatagramSocket

Constructor Summary

Constructors

Constructor and Description
MulticastSocket() Constructs a multicast socket, bound to any available port on the local host.
MulticastSocket(int port) Constructs a multicast socket, bound to the specified port on the local host.
MulticastSocket(SocketAddress localAddress) Constructs a MulticastSocket bound to the address and port specified by localAddress, or an unbound MulticastSocket if localAddress == null.

Method Summary

Modifier and Type	Method and Description
InetAddress	getInterface() Returns an address of the outgoing network interface used by this socket.
boolean	getLoopbackMode() Returns true if multicast loopback is disabled.
NetworkInterface	getNetworkInterface() Returns the outgoing network interface used by this socket.
int	getTimeToLive() Returns the time-to-live (TTL) for multicast packets sent on this socket.
byte	getTTL() Deprecated. Use getTimeToLive() instead.
void	joinGroup(InetAddress groupAddr) Adds this socket to the specified multicast group.
void	joinGroup(SocketAddress groupAddress, NetworkInterface netInterface) Adds this socket to the specified multicast group.
void	leaveGroup(InetAddress groupAddr) Removes this socket from the specified multicast group.
void	leaveGroup(SocketAddress groupAddress, NetworkInterface netInterface) Removes this socket from the specified multicast group.
void	send(DatagramPacket packet, byte ttl) Deprecated. Use setTimeToLive(int) instead.
void	setInterface(InetAddress address) Sets the outgoing network interface used by this socket.
void	setLoopbackMode(boolean disable) Disables multicast loopback if disable == true.
void	setNetworkInterface(NetworkInterface networkInterface) Sets the outgoing network interface used by this socket to the given networkInterface.
void	setTimeToLive(int ttl) Sets the time-to-live (TTL) for multicast packets sent on this socket.
void	setTTL(byte ttl) Deprecated. Use setTimeToLive(int) instead.

Methods inherited from class java.net.DatagramSocket

bind, close, connect, connect, disconnect, getBroadcast, getChannel, getFileDescriptor$, getInetAddress, getLocalAddress, getLocalPort, getLocalSocketAddress, getPort, getReceiveBufferSize, getRemoteSocketAddress, getReuseAddress, getReusePort, getSendBufferSize, getSoTimeout, getTrafficClass, isBound, isClosed, isConnected, onBind, onClose, onConnect, onDisconnect, receive, send, setBroadcast, setDatagramSocketImplFactory, setReceiveBufferSize, setReuseAddress, setReusePort, setSendBufferSize, setSoTimeout, setTrafficClass

Methods inherited from class java.lang.Object

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

Constructor Detail

MulticastSocket

public MulticastSocket()
                throws IOException

Constructs a multicast socket, bound to any available port on the local host.

Throws:

IOException - if an error occurs.

MulticastSocket

public MulticastSocket(int port)
                throws IOException

Constructs a multicast socket, bound to the specified port on the local host.

Throws:

IOException - if an error occurs.

MulticastSocket

public MulticastSocket(SocketAddress localAddress)
                throws IOException

Constructs a MulticastSocket bound to the address and port specified by localAddress, or an unbound MulticastSocket if localAddress == null.

Throws:

IllegalArgumentException - if localAddress is not supported (because it's not an InetSocketAddress, say).

IOException - if an error occurs.

Method Detail

getInterface

public InetAddress getInterface()
                         throws SocketException

Returns an address of the outgoing network interface used by this socket. To avoid inherent unpredictability, new code should use getNetworkInterface() instead.

Throws:

SocketException - if an error occurs.

getNetworkInterface

public NetworkInterface getNetworkInterface()
                                     throws SocketException

Returns the outgoing network interface used by this socket.

Throws:

SocketException - if an error occurs.

getTimeToLive

public int getTimeToLive()
                  throws IOException

Returns the time-to-live (TTL) for multicast packets sent on this socket.

Throws:

IOException - if an error occurs.

getTTL

@Deprecated
public byte getTTL()
                        throws IOException

Deprecated. Use getTimeToLive() instead.

Returns the time-to-live (TTL) for multicast packets sent on this socket.

Throws:

IOException - if an error occurs.

joinGroup

public void joinGroup(InetAddress groupAddr)
               throws IOException

Adds this socket to the specified multicast group. A socket must join a group before data may be received. A socket may be a member of multiple groups but may join any group only once.

Parameters:

groupAddr - the multicast group to be joined.

Throws:

IOException - if an error occurs.

joinGroup

public void joinGroup(SocketAddress groupAddress,
                      NetworkInterface netInterface)
               throws IOException

Adds this socket to the specified multicast group. A socket must join a group before data may be received. A socket may be a member of multiple groups but may join any group only once.

Parameters:

groupAddress - the multicast group to be joined.

netInterface - the network interface on which the datagram packets will be received.

Throws:

IOException - if the specified address is not a multicast address.

IllegalArgumentException - if no multicast group is specified.

leaveGroup

public void leaveGroup(InetAddress groupAddr)
                throws IOException

Removes this socket from the specified multicast group.

Parameters:

groupAddr - the multicast group to be left.

Throws:

NullPointerException - if groupAddr is null.

IOException - if the specified group address is not a multicast address.

leaveGroup

public void leaveGroup(SocketAddress groupAddress,
                       NetworkInterface netInterface)
                throws IOException

Removes this socket from the specified multicast group.

Parameters:

groupAddress - the multicast group to be left.

netInterface - the network interface on which the addresses should be dropped.

Throws:

IOException - if the specified group address is not a multicast address.

IllegalArgumentException - if groupAddress is null.

send

@Deprecated
public void send(DatagramPacket packet,
                             byte ttl)
                      throws IOException

Deprecated. Use setTimeToLive(int) instead.

Sends the given packet on this socket, using the given ttl. This method is deprecated because it modifies the TTL socket option for this socket twice on each call.

Throws:

IOException - if an error occurs.

setInterface

public void setInterface(InetAddress address)
                  throws SocketException

Sets the outgoing network interface used by this socket. The interface used is the first interface found to have the given address. To avoid inherent unpredictability, new code should use getNetworkInterface() instead.

Throws:

SocketException - if an error occurs.

setNetworkInterface

public void setNetworkInterface(NetworkInterface networkInterface)
                         throws SocketException

Sets the outgoing network interface used by this socket to the given networkInterface.

Overrides:

setNetworkInterface in class DatagramSocket

Throws:

SocketException - if an error occurs.

setTimeToLive

public void setTimeToLive(int ttl)
                   throws IOException

Sets the time-to-live (TTL) for multicast packets sent on this socket. Valid TTL values are between 0 and 255 inclusive.

Throws:

IOException - if an error occurs.

setTTL

@Deprecated
public void setTTL(byte ttl)
                        throws IOException

Deprecated. Use setTimeToLive(int) instead.

Sets the time-to-live (TTL) for multicast packets sent on this socket. Valid TTL values are between 0 and 255 inclusive.

Throws:

IOException - if an error occurs.

getLoopbackMode

public boolean getLoopbackMode()
                        throws SocketException

Returns true if multicast loopback is disabled. See SocketOptions.IP_MULTICAST_LOOP, and note that the sense of this is the opposite of the underlying Unix IP_MULTICAST_LOOP.

Throws:

SocketException - if an error occurs.

setLoopbackMode

public void setLoopbackMode(boolean disable)
                     throws SocketException

Disables multicast loopback if disable == true. See SocketOptions.IP_MULTICAST_LOOP, and note that the sense of this is the opposite of the underlying Unix IP_MULTICAST_LOOP: true means disabled, false means enabled.

Throws:

SocketException - if an error occurs.