Field Summary

Method Summary

Field Details

• TCP_NODELAY

  @Nativestatic final int TCP_NODELAY

  SeeStandardSocketOptions.TCP_NODELAY for description of this socket option.

  See Also:

  • Socket.setTcpNoDelay(boolean)
  • Socket.getTcpNoDelay()
  • Constant Field Values

• SO_BINDADDR

  @Nativestatic final int SO_BINDADDR

  Fetch the local address binding of a socket. This option cannot be set and can only be fetched. The default local address of a socket isINADDR_ANY, meaning any local address on a multi-homed host. A multi-homed host can use this option to accept connections to only one of its addresses (in the case of aServerSocket orDatagramSocket), or to specify its return address to the peer (for aSocket orDatagramSocket). The type of this option's value is anInetAddress.

  See Also:

  • Socket.getLocalAddress()
  • DatagramSocket.getLocalAddress()
  • Constant Field Values

• SO_REUSEADDR

  @Nativestatic final int SO_REUSEADDR

  SeeStandardSocketOptions.SO_REUSEADDR for description of this socket option.

  See Also:

  • Constant Field Values

• SO_REUSEPORT

  @Nativestatic final int SO_REUSEPORT

  SeeStandardSocketOptions.SO_REUSEPORT for description of this socket option.

  Since:

  9

  See Also:

  • Constant Field Values

• SO_BROADCAST

  @Nativestatic final int SO_BROADCAST

  SeeStandardSocketOptions.SO_BROADCAST for description of this socket option.

  Since:

  1.4

  See Also:

  • Constant Field Values

• IP_MULTICAST_IF

  @Nativestatic final int IP_MULTICAST_IF

  SeeStandardSocketOptions.IP_MULTICAST_IF for description of this socket option.

  See Also:

  • MulticastSocket.setInterface(InetAddress)
  • MulticastSocket.getInterface()
  • Constant Field Values

• IP_MULTICAST_IF2

  @Nativestatic final int IP_MULTICAST_IF2

  This option is used to both set and fetch the outgoing interface on which the multicast packets are sent. Useful on hosts with multiple network interfaces, where applications want to use other than the system default. This option supports setting outgoing interfaces with either IPv4 and IPv6 addresses.

  Since:

  1.4

  See Also:

  • MulticastSocket.setNetworkInterface(NetworkInterface)
  • MulticastSocket.getNetworkInterface()
  • Constant Field Values

• IP_MULTICAST_LOOP

  @Nativestatic final int IP_MULTICAST_LOOP

  SeeStandardSocketOptions.IP_MULTICAST_LOOP for description of this socket option.

  Since:

  1.4

  See Also:

  • Constant Field Values

• IP_TOS

  @Nativestatic final int IP_TOS

  SeeStandardSocketOptions.IP_TOS for description of this socket option.

  Since:

  1.4

  See Also:

  • Constant Field Values

• SO_LINGER

  @Nativestatic final int SO_LINGER

  SeeStandardSocketOptions.SO_LINGER for description of this socket option.

  Set the value toBoolean.FALSE or an integer less than0 withsetOption(int, Object) to disable this option. An integer greater than or equal to0 will enable the option and will represent the linger interval.

  If this option is enabled thengetOption(int) will return an integer value representing the linger interval, else the return value will beBoolean.FALSE.

  See Also:

  • Socket.setSoLinger(boolean, int)
  • Socket.getSoLinger()
  • Constant Field Values

• SO_TIMEOUT

  @Nativestatic final int SO_TIMEOUT

  This option is used to both set and fetch a timeout value on blockingSocket operations:

  • ServerSocket.accept()
  • Socket InputStream.read()
  • DatagramSocket.receive()

  This option must be set prior to entering a blocking operation to take effect. If the timeout expires and the operation would continue to block, thenInterruptedIOException is raised. TheSocket is not closed in such cases.

  See Also:

  • Socket.setSoTimeout(int)
  • ServerSocket.setSoTimeout(int)
  • DatagramSocket.setSoTimeout(int)
  • Constant Field Values

• SO_SNDBUF

  @Nativestatic final int SO_SNDBUF

  SeeStandardSocketOptions.SO_SNDBUF for description of this socket option.

  See Also:

  • Socket.setSendBufferSize(int)
  • Socket.getSendBufferSize()
  • DatagramSocket.setSendBufferSize(int)
  • DatagramSocket.getSendBufferSize()
  • Constant Field Values

• SO_RCVBUF

  @Nativestatic final int SO_RCVBUF

  SeeStandardSocketOptions.SO_RCVBUF for description of this socket option.

  See Also:

  • Socket.setReceiveBufferSize(int)
  • Socket.getReceiveBufferSize()
  • DatagramSocket.setReceiveBufferSize(int)
  • DatagramSocket.getReceiveBufferSize()
  • Constant Field Values

• SO_KEEPALIVE

  @Nativestatic final int SO_KEEPALIVE

  SeeStandardSocketOptions.SO_KEEPALIVE for description of this socket option.

  See Also:

  • Socket.setKeepAlive(boolean)
  • Socket.getKeepAlive()
  • Constant Field Values

• SO_OOBINLINE

  @Nativestatic final int SO_OOBINLINE

  When this option is set, any TCP urgent data received on the socket will be received through the socket input stream. When the option is disabled (which is the default) urgent data is silently discarded.

  See Also:

  • Socket.setOOBInline(boolean)
  • Socket.getOOBInline()
  • Constant Field Values

Method Details

• setOption

  void setOption(int optID,Object value) throwsSocketException

  Enable/disable the option specified byoptID. If the option is to be enabled, and it takes an option-specific "value", this is passed invalue. The actual type ofvalue is option-specific, and it is an error to pass something that isn't of the expected type:

  Copy

   SocketImpl s; ... s.setOption(SO_LINGER, Integer.valueOf(10));    // OK - set SO_LINGER w/ timeout of 10 sec. s.setOption(SO_LINGER, Double.valueOf(10));    // ERROR - expects java.lang.Integer

  If the requested option is binary, it can be set using this method by aBoolean:

  Copy

  s.setOption(TCP_NODELAY, Boolean.TRUE);   // OK - enables TCP_NODELAY, a binary option

  Any option can be disabled using this method with aBoolean.FALSE:

  Copy

  s.setOption(TCP_NODELAY, Boolean.FALSE);   // OK - disables TCP_NODELAYs.setOption(SO_LINGER, Boolean.FALSE);   // OK - disables SO_LINGER

  For an option that has a notion of on and off, and requires a non-boolean parameter, setting its value to anything other thanBoolean.FALSE implicitly enables it.

  Parameters:

  optID - identifies the option

  value - the parameter of the socket option

  Throws:

  SocketException - if the option is unrecognized, the socket is closed, or some low-level error occurred

  See Also:

  • getOption(int)

• getOption

  Object getOption(int optID) throwsSocketException

  Fetch the value of an option. Binary options will returnBoolean.TRUE if enabled,Boolean.FALSE if disabled, e.g.:

  Copy

  SocketImpl s;...Boolean noDelay = (Boolean)(s.getOption(TCP_NODELAY));if (noDelay.booleanValue()) {    // true if TCP_NODELAY is enabled......}

  For options that take a particular type as a parameter, this method will return the parameter's value, else it will returnBoolean.FALSE:

  Copy

  Object o = s.getOption(SO_LINGER);if (o instanceof Integer) {    System.out.print("Linger time is " + ((Integer)o).intValue());} else {  // the true type of o is java.lang.Boolean.FALSE;}

  Parameters:

  optID - anint identifying the option to fetch

  Returns:

  the value of the option

  Throws:

  SocketException - if the socket is closed or ifoptID is unknown along the protocol stack

  See Also:

  • setOption(int, java.lang.Object)