Package java.net

Interface SocketOptions

All Known Implementing Classes:
DatagramSocketImpl, PlainDatagramSocketImpl, PlainServerSocketImpl, PlainSocketImpl, SocketImpl
public interface SocketOptions
Defines an interface for socket implementations to get and set socket options. It is implemented by the classes SocketImpl and DatagramSocketImpl.
See Also:
SocketImpl, DatagramSocketImpl

  • Field Summary

    Fields
    Modifier and Type Field Description
    static int IP_MULTICAST_IF
    This is an IPv4-only socket option whose functionality is subsumed by IP_MULTICAST_IF and not implemented on Android.
    static int IP_MULTICAST_IF2
    This integer option sets the outgoing interface for multicast packets using an interface index.
    static int IP_MULTICAST_LOOP
    This boolean option specifies whether the local loopback of multicast packets is enabled or disabled.
    static int IP_TOS
    This integer option specifies the value for the type-of-service field of the IPv4 header, or the traffic class field of the IPv6 header.
    static int SO_BINDADDR
    This option does not correspond to any Unix socket option and is not implemented on Android.
    static int SO_BROADCAST
    This boolean option can be used to enable broadcasting on datagram sockets.
    static int SO_KEEPALIVE
    This boolean option specifies whether the kernel sends keepalive messages.
    static int SO_LINGER
    Number of seconds to wait when closing a socket if there is still some buffered data to be sent.
    static int SO_OOBINLINE
    This boolean option specifies whether sending TCP urgent data is supported on this socket or not.
    static int SO_RCVBUF
    The size in bytes of a socket's receive buffer.
    static int SO_REUSEADDR
    This boolean option specifies whether a reuse of a local address is allowed even if another socket is not yet removed by the operating system.
    static int SO_SNDBUF
    The size in bytes of a socket's send buffer.
    static int SO_TIMEOUT
    Integer timeout in milliseconds for blocking accept or read/receive operations (but not write/send operations).
    static int TCP_NODELAY
    This boolean option specifies whether data is sent immediately on this socket.

  • Method Summary

    Modifier and Type Method Description
    Object getOption​(int optID)
    Gets the value for the specified socket option.
    void setOption​(int optID, Object val)
    Sets the value of the specified socket option.

  • Field Details

    • SO_LINGER

      static final int SO_LINGER
      Number of seconds to wait when closing a socket if there is still some buffered data to be sent.

      If this option is set to 0, the TCP socket is closed forcefully and the call to close returns immediately.

      If this option is set to a value greater than 0, the value is interpreted as the number of seconds to wait. If all data could be sent during this time, the socket is closed normally. Otherwise the connection will be closed forcefully.

      Valid values for this option are in the range 0 to 65535 inclusive. (Larger timeouts will be treated as 65535s timeouts; roughly 18 hours.)

      See Also:
      Constant Field Values

    • SO_TIMEOUT

      static final int SO_TIMEOUT
      Integer timeout in milliseconds for blocking accept or read/receive operations (but not write/send operations). A timeout of 0 means no timeout. Negative timeouts are not allowed.

      An InterruptedIOException is thrown if this timeout expires.

      See Also:
      Constant Field Values

    • TCP_NODELAY

      static final int TCP_NODELAY
      This boolean option specifies whether data is sent immediately on this socket. As a side-effect this could lead to low packet efficiency. The socket implementation uses the Nagle's algorithm to try to reach a higher packet efficiency if this option is disabled.
      See Also:
      Constant Field Values

    • IP_MULTICAST_IF

      static final int IP_MULTICAST_IF
      This is an IPv4-only socket option whose functionality is subsumed by IP_MULTICAST_IF and not implemented on Android.
      See Also:
      Constant Field Values

    • SO_BINDADDR

      static final int SO_BINDADDR
      This option does not correspond to any Unix socket option and is not implemented on Android.
      See Also:
      Constant Field Values

    • SO_REUSEADDR

      static final int SO_REUSEADDR
      This boolean option specifies whether a reuse of a local address is allowed even if another socket is not yet removed by the operating system. It's only available on a MulticastSocket.
      See Also:
      Constant Field Values

    • SO_SNDBUF

      static final int SO_SNDBUF
      The size in bytes of a socket's send buffer. This must be an integer greater than 0. This is a hint to the kernel; the kernel may use a larger buffer.

      For datagram sockets, it is implementation-defined whether packets larger than this size can be sent.

      See Also:
      Constant Field Values

    • SO_RCVBUF

      static final int SO_RCVBUF
      The size in bytes of a socket's receive buffer. This must be an integer greater than 0. This is a hint to the kernel; the kernel may use a larger buffer.

      For datagram sockets, packets larger than this value will be discarded.

      See Also:
      Constant Field Values

    • SO_KEEPALIVE

      static final int SO_KEEPALIVE
      This boolean option specifies whether the kernel sends keepalive messages.
      See Also:
      Constant Field Values

    • IP_TOS

      static final int IP_TOS
      This integer option specifies the value for the type-of-service field of the IPv4 header, or the traffic class field of the IPv6 header. These correspond to the IP_TOS and IPV6_TCLASS socket options. These may be ignored by the underlying OS. Values must be between 0 and 255 inclusive.

      See RFC 1349 for more about IPv4 and RFC 2460 for more about IPv6.

      See Also:
      Constant Field Values

    • IP_MULTICAST_LOOP

      static final int IP_MULTICAST_LOOP
      This boolean option specifies whether the local loopback of multicast packets is enabled or disabled. This option is enabled by default on multicast sockets. Note that the sense of this option in Java is the opposite of the underlying Unix IP_MULTICAST_LOOP. See MulticastSocket.setLoopbackMode(boolean).
      See Also:
      Constant Field Values

    • SO_BROADCAST

      static final int SO_BROADCAST
      This boolean option can be used to enable broadcasting on datagram sockets.
      See Also:
      Constant Field Values

    • SO_OOBINLINE

      static final int SO_OOBINLINE
      This boolean option specifies whether sending TCP urgent data is supported on this socket or not.
      See Also:
      Constant Field Values

    • IP_MULTICAST_IF2

      static final int IP_MULTICAST_IF2
      This integer option sets the outgoing interface for multicast packets using an interface index.
      See Also:
      Constant Field Values

  • Method Details

    • getOption

      Object getOption​(int optID) throws SocketException
      Gets the value for the specified socket option.
      Parameters:
      optID - the option identifier.
      Returns:
      the option value.
      Throws:
      SocketException - if an error occurs reading the option value.

    • setOption

      void setOption​(int optID, Object val) throws SocketException
      Sets the value of the specified socket option.
      Parameters:
      optID - the option identifier.
      val - the value to be set for the option.
      Throws:
      SocketException - if an error occurs setting the option value.