Constructor Summary

Method Summary

Constructor Details

• MulticastSocket

  public MulticastSocket() throwsIOException

  Constructs a multicast socket and binds it to any available port on the local host machine. The socket will be bound to thewildcard address.

  If there is a security manager, itscheckListen method is first called with 0 as its argument to ensure the operation is allowed. This could result in a SecurityException.

  When the socket is created theDatagramSocket.setReuseAddress(boolean) method is called to enable the SO_REUSEADDR socket option.

  Throws:

  IOException - if an I/O exception occurs while creating the MulticastSocket

  SecurityException - if a security manager exists and itscheckListen method doesn't allow the operation.

  See Also:

  • SecurityManager.checkListen(int)
  • DatagramSocket.setReuseAddress(boolean)
  • DatagramSocketImpl.setOption(SocketOption, Object)

• MulticastSocket

  public MulticastSocket(int port) throwsIOException

  Constructs a multicast socket and binds it to the specified port on the local host machine. The socket will be bound to thewildcard address.

  If there is a security manager, itscheckListen method is first called with theport argument as its argument to ensure the operation is allowed. This could result in a SecurityException.

  When the socket is created theDatagramSocket.setReuseAddress(boolean) method is called to enable the SO_REUSEADDR socket option.

  Parameters:

  port - port to use

  Throws:

  IOException - if an I/O exception occurs while creating the MulticastSocket

  SecurityException - if a security manager exists and itscheckListen method doesn't allow the operation.

  IllegalArgumentException - if port is out of range.

  See Also:

  • SecurityManager.checkListen(int)
  • DatagramSocket.setReuseAddress(boolean)

• MulticastSocket

  public MulticastSocket(SocketAddress bindaddr) throwsIOException

  Creates a multicast socket, bound to the specified local socket address.

  If the address isnull an unbound socket will be created.

  If there is a security manager, itscheckListen method is first called with the SocketAddress port as its argument to ensure the operation is allowed. This could result in a SecurityException.

  When the socket is created theDatagramSocket.setReuseAddress(boolean) method is called to enable the SO_REUSEADDR socket option.

  Parameters:

  bindaddr - Socket address to bind to, ornull for an unbound socket.

  Throws:

  IOException - if an I/O exception occurs while creating the MulticastSocket

  SecurityException - if a security manager exists and itscheckListen method doesn't allow the operation.

  Since:

  1.4

  See Also:

  • SecurityManager.checkListen(int)
  • DatagramSocket.setReuseAddress(boolean)

Method Details

• setTTL

  @Deprecatedpublic void setTTL(byte ttl) throwsIOException

  Deprecated.

  use thesetTimeToLive(int) method instead, which usesint instead ofbyte as the type for ttl.

  Set the default time-to-live for multicast packets sent out on thisMulticastSocket in order to control the scope of the multicasts.

  The ttl is anunsigned 8-bit quantity, and somust be in the range0 <= ttl <= 0xFF.

  Parameters:

  ttl - the time-to-live

  Throws:

  IOException - if an I/O exception occurs while setting the default time-to-live value

  See Also:

  • getTTL()

• setTimeToLive

  public void setTimeToLive(int ttl) throwsIOException

  Set the default time-to-live for multicast packets sent out on thisMulticastSocket in order to control the scope of the multicasts.

  The ttlmust be in the range 0 <= ttl <= 255 or anIllegalArgumentException will be thrown. Multicast packets sent with a TTL of0 are not transmitted on the network but may be delivered locally.

  API Note:

  This method is equivalent to callingsetOption(StandardSocketOptions.IP_MULTICAST_TTL, ttl).

  Parameters:

  ttl - the time-to-live

  Throws:

  IOException - if an I/O exception occurs while setting the default time-to-live value

  Since:

  1.2

  See Also:

  • getTimeToLive()
  • StandardSocketOptions.IP_MULTICAST_TTL

• getTTL

  @Deprecatedpublic byte getTTL() throwsIOException

  Deprecated.

  use thegetTimeToLive() method instead, which returns anint instead of abyte.

  Get the default time-to-live for multicast packets sent out on the socket.

  Returns:

  the default time-to-live value

  Throws:

  IOException - if an I/O exception occurs while getting the default time-to-live value

  See Also:

  • setTTL(byte)

• getTimeToLive

  public int getTimeToLive() throwsIOException

  Get the default time-to-live for multicast packets sent out on the socket.

  API Note:

  This method is equivalent to callinggetOption(StandardSocketOptions.IP_MULTICAST_TTL).

  Returns:

  the default time-to-live value

  Throws:

  IOException - if an I/O exception occurs while getting the default time-to-live value

  Since:

  1.2

  See Also:

  • setTimeToLive(int)
  • StandardSocketOptions.IP_MULTICAST_TTL

• joinGroup

  @Deprecated(since="14")public void joinGroup(InetAddress mcastaddr) throwsIOException

  Deprecated.

  This method does not accept the network interface on which to join the multicast group. UsejoinGroup(SocketAddress, NetworkInterface) instead.

  Joins a multicast group. Its behavior may be affected bysetInterface orsetNetworkInterface.

  If there is a security manager, this method first calls itscheckMulticast method with themcastaddr argument as its argument.

  API Note:

  Calling this method is equivalent to callingjoinGroup(new InetSocketAddress(mcastaddr, 0), null).

  Parameters:

  mcastaddr - is the multicast address to join

  Throws:

  IOException - if there is an error joining, or when the address is not a multicast address, or the platform does not support multicasting

  SecurityException - if a security manager exists and itscheckMulticast method doesn't allow the join.

  See Also:

  • SecurityManager.checkMulticast(InetAddress)

• leaveGroup

  @Deprecated(since="14")public void leaveGroup(InetAddress mcastaddr) throwsIOException

  Deprecated.

  This method does not accept the network interface on which to leave the multicast group. UseleaveGroup(SocketAddress, NetworkInterface) instead.

  Leave a multicast group. Its behavior may be affected bysetInterface orsetNetworkInterface.

  If there is a security manager, this method first calls itscheckMulticast method with themcastaddr argument as its argument.

  API Note:

  Calling this method is equivalent to callingleaveGroup(new InetSocketAddress(mcastaddr, 0), null).

  Parameters:

  mcastaddr - is the multicast address to leave

  Throws:

  IOException - if there is an error leaving or when the address is not a multicast address.

  SecurityException - if a security manager exists and itscheckMulticast method doesn't allow the operation.

  See Also:

  • SecurityManager.checkMulticast(InetAddress)

• joinGroup

  public void joinGroup(SocketAddress mcastaddr,NetworkInterface netIf) throwsIOException

  Joins a multicast group.

  In order to join a multicast group, the caller should specify the IP address of the multicast group to join, and the localnetwork interface to receive multicast packets from.

  • Themcastaddr argument indicates the IP address of the multicast group to join. For historical reasons this is specified as aSocketAddress. The default implementation only supportsInetSocketAddress and theport information is ignored.
  • ThenetIf argument specifies the local interface to receive multicast datagram packets, ornull to defer to the interface set for outgoing multicast datagrams. Ifnull, and no interface has been set, the behaviour is unspecified: any interface may be selected or the operation may fail with aSocketException.

  It is possible to call this method several times to join several different multicast groups, or join the same group in several different networks. However, if the socket is already a member of the group, anIOException will be thrown.

  If there is a security manager, this method first calls itscheckMulticast method with themcastaddr argument as its argument.

  Overrides:

  joinGroup in class DatagramSocket

  Parameters:

  mcastaddr - indicates the multicast address to join.

  netIf - specifies the local interface to receive multicast datagram packets, ornull.

  Throws:

  IOException - if there is an error joining, or when the address is not a multicast address, or the platform does not support multicasting

  SecurityException - if a security manager exists and itscheckMulticast method doesn't allow the join.

  IllegalArgumentException - if mcastaddr isnull or is a SocketAddress subclass not supported by this socket

  Since:

  1.4

  See Also:

  • SecurityManager.checkMulticast(InetAddress)
  • MulticastChannel.join(InetAddress, NetworkInterface)
  • StandardSocketOptions.IP_MULTICAST_IF
  • setNetworkInterface(NetworkInterface)
  • setInterface(InetAddress)

• leaveGroup

  public void leaveGroup(SocketAddress mcastaddr,NetworkInterface netIf) throwsIOException

  Leave a multicast group on a specified local interface.

  If there is a security manager, this method first calls itscheckMulticast method with themcastaddr argument as its argument.

  Overrides:

  leaveGroup in class DatagramSocket

  API Note:

  Themcastaddr andnetIf arguments should identify a multicast group that was previouslyjoined by thisDatagramSocket.

  It is possible to call this method several times to leave multiple different multicast groups previously joined, or leave the same group previously joined in multiple different networks. However, if the socket is not a member of the specified group in the specified network, anIOException will be thrown.

  Parameters:

  mcastaddr - is the multicast address to leave. This should contain the same IP address than that used forjoining the group.

  netIf - specifies the local interface ornull to defer to the interface set for outgoing multicast datagrams. Ifnull, and no interface has been set, the behaviour is unspecified: any interface may be selected or the operation may fail with aSocketException.

  Throws:

  IOException - if there is an error leaving or when the address is not a multicast address.

  SecurityException - if a security manager exists and itscheckMulticast method doesn't allow the operation.

  IllegalArgumentException - if mcastaddr isnull or is a SocketAddress subclass not supported by this socket.

  Since:

  1.4

  See Also:

  • SecurityManager.checkMulticast(InetAddress)
  • joinGroup(SocketAddress, NetworkInterface)

• setInterface

  @Deprecated(since="14")public void setInterface(InetAddress inf) throwsSocketException

  Deprecated.

  The InetAddress may not uniquely identify the network interface. UsesetNetworkInterface(NetworkInterface) instead.

  Set the multicast network interface used by methods whose behavior would be affected by the value of the network interface. Useful for multihomed hosts.

  Parameters:

  inf - the InetAddress

  Throws:

  SocketException - if there is an error in the underlying protocol, such as a TCP error.

  See Also:

  • getInterface()

• getInterface

  @Deprecated(since="14")public InetAddress getInterface() throwsSocketException

  Deprecated.

  The network interface may not be uniquely identified by the InetAddress returned. UsegetNetworkInterface() instead.

  Retrieve the address of the network interface used for multicast packets.

  Returns:

  AnInetAddress representing the address of the network interface used for multicast packets, or if no interface has been set, anInetAddress representing any local address.

  Throws:

  SocketException - if there is an error in the underlying protocol, such as a TCP error.

  See Also:

  • setInterface(java.net.InetAddress)

• setNetworkInterface

  public void setNetworkInterface(NetworkInterface netIf) throwsSocketException

  Specify the network interface for outgoing multicast datagrams sent on this socket.

  API Note:

  This method is equivalent to callingsetOption(StandardSocketOptions.IP_MULTICAST_IF, netIf).

  Parameters:

  netIf - the interface

  Throws:

  SocketException - if there is an error in the underlying protocol, such as a TCP error.

  Since:

  1.4

  See Also:

  • getNetworkInterface()
  • StandardSocketOptions.IP_MULTICAST_IF

• getNetworkInterface

  public NetworkInterface getNetworkInterface() throwsSocketException

  Get the multicast network interface set for outgoing multicast datagrams sent from this socket.

  API Note:

  When an interface is set, this method is equivalent to callinggetOption(StandardSocketOptions.IP_MULTICAST_IF).

  Returns:

  The multicastNetworkInterface currently set. A placeholder NetworkInterface is returned when there is no interface set; it has a single InetAddress to represent any local address.

  Throws:

  SocketException - if there is an error in the underlying protocol, such as a TCP error.

  Since:

  1.4

  See Also:

  • setNetworkInterface(NetworkInterface)
  • StandardSocketOptions.IP_MULTICAST_IF

• setLoopbackMode

  @Deprecated(since="14")public void setLoopbackMode(boolean disable) throwsSocketException

  Deprecated.

  UseDatagramSocket.setOption(SocketOption, Object) withStandardSocketOptions.IP_MULTICAST_LOOP instead. The loopback mode is enabled by default,MulticastSocket.setOption(StandardSocketOptions.IP_MULTICAST_LOOP, false) disables it.

  Disable/Enable local loopback of multicast datagrams. The option is used by the platform's networking code as a hint for setting whether multicast data will be looped back to the local socket.

  Because this option is a hint, applications that want to verify what loopback mode is set to should callgetLoopbackMode()

  Parameters:

  disable -true to disable the LoopbackMode

  Throws:

  SocketException - if an error occurs while setting the value

  Since:

  1.4

  See Also:

  • getLoopbackMode()

• getLoopbackMode

  @Deprecated(since="14")public boolean getLoopbackMode() throwsSocketException

  Deprecated.

  UseDatagramSocket.getOption(SocketOption) withStandardSocketOptions.IP_MULTICAST_LOOP instead.

  Get the setting for local loopback of multicast datagrams.

  Returns:

  true if the LoopbackMode has been disabled

  Throws:

  SocketException - if an error occurs while getting the value

  Since:

  1.4

  See Also:

  • setLoopbackMode(boolean)

• send

  @Deprecatedpublic void send(DatagramPacket p, byte ttl) throwsIOException

  Deprecated.

  Use the following code or its equivalent instead:

    ......  int ttl = mcastSocket.getOption(StandardSocketOptions.IP_MULTICAST_TTL);  mcastSocket.setOption(StandardSocketOptions.IP_MULTICAST_TTL, newttl);  mcastSocket.send(p);  mcastSocket.setOption(StandardSocketOptions.IP_MULTICAST_TTL, ttl);  ......

  Sends a datagram packet to the destination, with a TTL (time-to-live) other than the default for the socket. This method need only be used in instances where a particular TTL is desired; otherwise it is preferable to set a TTL once on the socket, and use that default TTL for all packets. This method doesnot alter the default TTL for the socket. Its behavior may be affected bysetInterface.

  If there is a security manager, this method first performs some security checks. First, ifp.getAddress().isMulticastAddress() is true, this method calls the security manager'scheckMulticast method withp.getAddress() andttl as its arguments. If the evaluation of that expression is false, this method instead calls the security manager'scheckConnect method with argumentsp.getAddress().getHostAddress() andp.getPort(). Each call to a security manager method could result in a SecurityException if the operation is not allowed.

  Parameters:

  p - is the packet to be sent. The packet should contain the destination multicast ip address and the data to be sent. One does not need to be the member of the group to send packets to a destination multicast address.

  ttl - optional time to live for multicast packet. default ttl is 1.

  Throws:

  IOException - is raised if an error occurs i.e error while setting ttl.

  SecurityException - if a security manager exists and itscheckMulticast orcheckConnect method doesn't allow the send.

  PortUnreachableException - may be thrown if the socket is connected to a currently unreachable destination. Note, there is no guarantee that the exception will be thrown.

  IllegalArgumentException - if the socket is connected, and connected address and packet address differ, or if the socket is not connected and the packet address is not set or if its port is out of range.

  See Also:

  • DatagramSocket.send(java.net.DatagramPacket)
  • DatagramSocket.receive(java.net.DatagramPacket)
  • SecurityManager.checkMulticast(java.net.InetAddress, byte)
  • SecurityManager.checkConnect(java.lang.String, int)