/* SocketOptions.java -- Implements options for sockets (duh!)
   Copyright (C) 1998, 1999, 2000, 2001, 
                 2002, 2003 Free Software Foundation, Inc.

This file is part of GNU Classpath.

GNU Classpath is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
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any later version.
 
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02111-1307 USA.

Linking this library statically or dynamically with other modules is
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As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
executable, regardless of the license terms of these independent
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terms of your choice, provided that you also meet, for each linked
independent module, the terms and conditions of the license of that
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package java.net;

/**
 * Written using on-line Java Platform 1.2 API Specification.
 * Status:  Believed complete and correct.
 */

/**
 * This interface is used by <code>SocketImpl</code> and 
 * <code>DatagramSocketImpl</code> to implement options
 * on sockets.  
 *
 * @since 1.2
 *
 * @author Aaron M. Renn (arenn@urbanophile.com)
 * @author Warren Levy <warrenl@cygnus.com>
 * @status should be completely JDK 1.4 compatible
 */
public interface SocketOptions
{
  /**
   * Option id for the SO_KEEPALIVE value
   * @since 1.3
   */
  int SO_KEEPALIVE = 0x8;

  /**
   * Option id for the SO_LINGER value
   */
  int SO_LINGER = 0x80; // 128

  /**
   * Option id for the SO_TIMEOUT value
   */
  int SO_TIMEOUT = 0x1006; // 4102

  /**
   * Retrieve the local address to which the socket is bound.
   */
  int SO_BINDADDR = 0x0F; // 15

  /**
   * Option id for the send buffer size
   * @since 1.2
   */
  int SO_SNDBUF = 0x1001; // 4097

  /**
   * Option id for the receive buffer size
   * @since 1.2
   */
  int SO_RCVBUF = 0x1002; // 4098

  /**
   * Sets the SO_REUSEADDR parameter on a socket
   */
  int SO_REUSEADDR = 0x04; // 4

  /**
   * Sets SO_BROADCAST for a socket
   * @since 1.4
   */
  int SO_BROADCAST = 0x20; // 32

  /**
   * Sets SO_OOBINLINE for a socket
   * @since 1.4
   */
  int SO_OOBINLINE = 0x1003; // 4099

  /**
   * Option id for the TCP_NODELAY value
   */
  int TCP_NODELAY = 0x01; // 1

  /**
   * Options id for the IP_MULTICAST_IF value
   */
  int IP_MULTICAST_IF = 0x10; // 16

  /**
   * same as above
   * @since 1.4
   */
  int IP_MULTICAST_IF2 = 0x1F; // 31

  /**
   * This option enables or disables local loopback of multicast datagrams.
   * @since 1.4
   */
  int IP_MULTICAST_LOOP = 0x12; // 18

  /**
   * This option sets the type-of-service or traffic class field in the
   * IP header for a TCP or UDP socket.
   * @since 1.4
   */
  int IP_TOS = 0x03; // 3

  /**
   * Sets the specified option on a socket to the passed in object.  For
   * options that take an integer argument, the passed in object is an
   * <code>Integer</code>.  For options that are set to on or off, the
   * value passed will be a <code>Boolean</code>.   The <code>optionId</code>
   * parameter is one of the defined constants in this interface.
   *
   * @param optionId The identifier of the option
   * @param val The value to set the option to
   *
   * @exception SocketException If an error occurs
   */
  void setOption(int optionId, Object val) throws SocketException;

  /**
   * Returns the current setting of the specified option.  The
   * <code>Object</code> returned will be an <code>Integer</code> for options
   * that have integer values.  For options that are set to on or off, a
   * <code>Boolean</code> will be returned.   The <code>optionId</code>
   * parameter is one of the defined constants in this interface.
   *
   * @param optionId The option identifier
   *
   * @return The current value of the option
   *
   * @exception SocketException If an error occurs
   */
  Object getOption(int optionId) throws SocketException;

} // interface SocketOptions