/* SocketOptions.java -- Implements options for sockets (duh!)
   Copyright (C) 1998, 1999, 2000, 2001 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
the Free Software Foundation; either version 2, or (at your option)
any later version.
 
GNU Classpath is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
General Public License for more details.

You should have received a copy of the GNU General Public License
along with GNU Classpath; see the file COPYING.  If not, write to the
Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA.

As a special exception, if you link this library with other files to
produce an executable, this library does not by itself cause the
resulting executable to be covered by the GNU General Public License.
This exception does not however invalidate any other reasons why the
executable file might be covered by the GNU General Public License. */

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>
  */
public interface SocketOptions
{

/*************************************************************************/

/*
 * Static Variables
 */

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

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

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

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

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

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

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

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

/*************************************************************************/

/*
 * Interface Methods
 */

/**
  * 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>option_id</code> 
  * parameter is one of the defined constants in this interface.
  *
  * @param option_id The identifier of the option
  * @param val The value to set the option to
  *
  * @exception SocketException If an error occurs
  */
void
setOption(int option_id, 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>option_id</code>
  * is one of the defined constants in this interface.
  *
  * @param option_id The option identifier
  *
  * @return The current value of the option
  *
  * @exception SocketException If an error occurs
  */
Object
getOption(int option_id) throws SocketException;

} // interface SocketOptions