https://openjdk.java.net/ 
/*
 * Copyright (c) 2009, 2017, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code 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
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
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 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package com.sun.nio.sctp;

import java.net.SocketAddress;
import java.net.InetAddress;
import java.io.IOException;
import java.util.Set;
import java.nio.ByteBuffer;
import java.nio.channels.spi.AbstractSelectableChannel;
import java.nio.channels.spi.SelectorProvider;
import java.nio.channels.ClosedChannelException;
import java.nio.channels.SelectionKey;


A selectable channel for message-oriented connected SCTP sockets.

 An SCTP channel can only control one SCTP association. An SCTPChannel is created by invoking one of the open methods of this class. A newly-created channel is open but not yet connected, that is, there is no association setup with a remote peer. An attempt to invoke an I/O operation upon an unconnected channel will cause a NotYetConnectedException to be thrown. An association can be setup by connecting the channel using one of its connect methods. Once connected, the channel remains connected until it is closed. Whether or not a channel is connected may be determined by invoking getRemoteAddresses. 
 SCTP channels support non-blocking connection: A channel may be created and the process of establishing the link to the remote socket may be initiated via the connect method for later completion by the finishConnect method. Whether or not a connection operation is in progress may be determined by invoking the isConnectionPending method. 
 Socket options are configured using the setOption method. An SCTP channel support the following options: 



  Socket options
  
  

    Option Name
    Description
  

  
  
  

     
                                         SCTP_DISABLE_FRAGMENTS 
     Enables or disables message fragmentation 
  

  

     
                                         SCTP_EXPLICIT_COMPLETE 
     Enables or disables explicit message completion 
  

   

     
                                         SCTP_FRAGMENT_INTERLEAVE 
     Controls how the presentation of messages occur for the message
         receiver 
  

  

     
                                         SCTP_INIT_MAXSTREAMS 
     The maximum number of streams requested by the local endpoint during
         association initialization 
  

  

     SCTP_NODELAY 
     Enables or disable a Nagle-like algorithm 
  

  

     
                                         SCTP_PRIMARY_ADDR 
     Requests that the local SCTP stack use the given peer address as the
         association primary 
  

  

     
                                         SCTP_SET_PEER_PRIMARY_ADDR 
     Requests that the peer mark the enclosed address as the association
         primary 
  

  

     
                                         SO_SNDBUF 
     The size of the socket send buffer 
  

  

     
                                         SO_RCVBUF 
     The size of the socket receive buffer 
  

  

     
                                         SO_LINGER 
     Linger on close if data is present (when configured in blocking mode
         only) 
  

  



 Additional (implementation specific) options may also be supported. The list of options supported is obtained by invoking the 
supportedOptions method. 
 SCTP channels are safe for use by multiple concurrent threads. They support concurrent reading and writing, though at most one thread may be reading and at most one thread may be writing at any given time. The connect and 
finishConnect methods are mutually synchronized against each other, and an attempt to initiate a send or receive operation while an invocation of one of these methods is in progress will block until that invocation is complete. 
Since:1.7
/**
 * A selectable channel for message-oriented connected SCTP sockets.
 *
 * <P> An SCTP channel can only control one SCTP association.
 * An {@code SCTPChannel} is created by invoking one of the
 * {@link #open open} methods of this class. A newly-created channel is open but
 * not yet connected, that is, there is no association setup with a remote peer.
 * An attempt to invoke an I/O operation upon an unconnected
 * channel will cause a {@link java.nio.channels.NotYetConnectedException} to be
 * thrown. An association can be setup by connecting the channel using one of
 * its {@link #connect connect} methods. Once connected, the channel remains
 * connected until it is closed. Whether or not a channel is connected may be
 * determined by invoking {@link #getRemoteAddresses getRemoteAddresses}.
 *
 * <p> SCTP channels support <i>non-blocking connection:</i>&nbsp;A
 * channel may be created and the process of establishing the link to
 * the remote socket may be initiated via the {@link #connect connect} method
 * for later completion by the {@link #finishConnect finishConnect} method.
 * Whether or not a connection operation is in progress may be determined by
 * invoking the {@link #isConnectionPending isConnectionPending} method.
 *
 * <p> Socket options are configured using the
 * {@link #setOption(SctpSocketOption,Object) setOption} method. An SCTP
 * channel support the following options:
 * <blockquote>
 * <table class="striped">
 *   <caption style="display:none">Socket options</caption>
 *   <thead>
 *   <tr>
 *     <th scope="col">Option Name</th>
 *     <th scope="col">Description</th>
 *   </tr>
 *   </thead>
 *   <tbody>
 *   <tr>
 *     <th scope="row"> {@link SctpStandardSocketOptions#SCTP_DISABLE_FRAGMENTS
 *                                          SCTP_DISABLE_FRAGMENTS} </th>
 *     <td> Enables or disables message fragmentation </td>
 *   </tr>
 *   <tr>
 *     <th scope="row"> {@link SctpStandardSocketOptions#SCTP_EXPLICIT_COMPLETE
 *                                          SCTP_EXPLICIT_COMPLETE} </th>
 *     <td> Enables or disables explicit message completion </td>
 *   </tr>
 *    <tr>
 *     <th scope="row"> {@link SctpStandardSocketOptions#SCTP_FRAGMENT_INTERLEAVE
 *                                          SCTP_FRAGMENT_INTERLEAVE} </th>
 *     <td> Controls how the presentation of messages occur for the message
 *          receiver </td>
 *   </tr>
 *   <tr>
 *     <th scope="row"> {@link SctpStandardSocketOptions#SCTP_INIT_MAXSTREAMS
 *                                          SCTP_INIT_MAXSTREAMS} </th>
 *     <td> The maximum number of streams requested by the local endpoint during
 *          association initialization </td>
 *   </tr>
 *   <tr>
 *     <th scope="row"> {@link SctpStandardSocketOptions#SCTP_NODELAY SCTP_NODELAY} </th>
 *     <td> Enables or disable a Nagle-like algorithm </td>
 *   </tr>
 *   <tr>
 *     <th scope="row"> {@link SctpStandardSocketOptions#SCTP_PRIMARY_ADDR
 *                                          SCTP_PRIMARY_ADDR} </th>
 *     <td> Requests that the local SCTP stack use the given peer address as the
 *          association primary </td>
 *   </tr>
 *   <tr>
 *     <th scope="row"> {@link SctpStandardSocketOptions#SCTP_SET_PEER_PRIMARY_ADDR
 *                                          SCTP_SET_PEER_PRIMARY_ADDR} </th>
 *     <td> Requests that the peer mark the enclosed address as the association
 *          primary </td>
 *   </tr>
 *   <tr>
 *     <th scope="row"> {@link SctpStandardSocketOptions#SO_SNDBUF
 *                                          SO_SNDBUF} </th>
 *     <td> The size of the socket send buffer </td>
 *   </tr>
 *   <tr>
 *     <th scope="row"> {@link SctpStandardSocketOptions#SO_RCVBUF
 *                                          SO_RCVBUF} </th>
 *     <td> The size of the socket receive buffer </td>
 *   </tr>
 *   <tr>
 *     <th scope="row"> {@link SctpStandardSocketOptions#SO_LINGER
 *                                          SO_LINGER} </th>
 *     <td> Linger on close if data is present (when configured in blocking mode
 *          only) </td>
 *   </tr>
 *   </tbody>
 * </table>
 * </blockquote>
 * Additional (implementation specific) options may also be supported. The list
 * of options supported is obtained by invoking the {@link #supportedOptions()
 * supportedOptions}  method.
 *
 * <p> SCTP channels are safe for use by multiple concurrent threads.
 * They support concurrent reading and writing, though at most one thread may be
 * reading and at most one thread may be writing at any given time. The
 * {@link #connect connect} and {@link #finishConnect
 * finishConnect} methods are mutually synchronized against each other, and
 * an attempt to initiate a send or receive operation while an invocation of one
 * of these methods is in progress will block until that invocation is complete.
 *
 * @since 1.7
 */
public abstract class SctpChannel
    extends AbstractSelectableChannel
{
    
Initializes a new instance of this class.

Params:
  • provider – 
        The selector provider for this channel
/**
     * Initializes a new instance of this class.
     *
     * @param  provider
     *         The selector provider for this channel
     */
    protected SctpChannel(SelectorProvider provider) {
        super(provider);
    }

    
Opens an SCTP channel.

 The new channel is unbound and unconnected.

Throws:
Returns: A new SCTP channel
/**
     * Opens an SCTP channel.
     *
     * <P> The new channel is unbound and unconnected.
     *
     * @return  A new SCTP channel
     *
     * @throws  UnsupportedOperationException
     *          If the SCTP protocol is not supported
     *
     * @throws  IOException
     *          If an I/O error occurs
     */
    public static SctpChannel open() throws
        IOException {
        return new sun.nio.ch.sctp.SctpChannelImpl((SelectorProvider)null);
    }

    
Opens an SCTP channel and connects it to a remote address.

 This is a convenience method and is equivalent to evaluating the
following expression:

open().connect(remote, maxOutStreams, maxInStreams);



Params:
  • remote – 
        The remote address to which the new channel is to be connected
  • maxOutStreams –  The number of streams that the application wishes to be able to send to. Must be non negative and no larger than 65536. 0 to use the endpoints default value.
  • maxInStreams –  The maximum number of inbound streams the application is prepared to support. Must be non negative and no larger than 65536. 0 to use the endpoints default value.
Throws:
Returns: A new SCTP channel connected to the given address
/**
     * Opens an SCTP channel and connects it to a remote address.
     *
     * <P> This is a convenience method and is equivalent to evaluating the
     * following expression:
     * <blockquote><pre>
     * open().connect(remote, maxOutStreams, maxInStreams);
     * </pre></blockquote>
     *
     * @param  remote
     *         The remote address to which the new channel is to be connected
     *
     * @param  maxOutStreams
     *         The number of streams that the application wishes to be able
     *         to send to. Must be non negative and no larger than {@code 65536}.
     *         {@code 0} to use the endpoints default value.
     *
     * @param  maxInStreams
     *         The maximum number of inbound streams the application is prepared
     *         to support. Must be non negative and no larger than {@code 65536}.
     *         {@code 0} to use the endpoints default value.
     *
     * @return  A new SCTP channel connected to the given address
     *
     * @throws  java.nio.channels.AsynchronousCloseException
     *          If another thread closes this channel
     *          while the connect operation is in progress
     *
     * @throws  java.nio.channels.ClosedByInterruptException
     *          If another thread interrupts the current thread
     *          while the connect operation is in progress, thereby
     *          closing the channel and setting the current thread's
     *          interrupt status
     *
     * @throws  java.nio.channels.UnresolvedAddressException
     *          If the given remote address is not fully resolved
     *
     * @throws  java.nio.channels.UnsupportedAddressTypeException
     *          If the type of the given remote address is not supported
     *
     * @throws  SecurityException
     *          If a security manager has been installed
     *          and it does not permit access to the given remote peer
     *
     * @throws  UnsupportedOperationException
     *          If the SCTP protocol is not supported
     *
     * @throws  IOException
     *          If some other I/O error occurs
     */
    public static SctpChannel open(SocketAddress remote, int maxOutStreams,
                   int maxInStreams) throws IOException {
        SctpChannel ssc = SctpChannel.open();
        ssc.connect(remote, maxOutStreams, maxInStreams);
        return ssc;
    }

    
Returns the association on this channel's socket.

Throws:
Returns: the association, or null if the channel's socket is not connected.
/**
     * Returns the association on this channel's socket.
     *
     * @return  the association, or {@code null} if the channel's socket is not
     *          connected.
     *
     * @throws  ClosedChannelException
     *          If the channel is closed
     *
     * @throws  IOException
     *          If some other I/O error occurs
     */
    public abstract Association association() throws IOException;

    
Binds the channel's socket to a local address.

 This method is used to establish a relationship between the socket and the local addresses. Once a relationship is established then the socket remains bound until the channel is closed. This relationship may not necesssarily be with the address local as it may be removed by unbindAddress, but there will always be at least one local address bound to the channel's socket once an invocation of this method successfully completes. 
 Once the channel's socket has been successfully bound to a specific address, that is not automatically assigned, more addresses may be bound to it using bindAddress, or removed using unbindAddress. 
Params:
  • local –  The local address to bind the socket, or null to bind the socket to an automatically assigned socket address
Throws:
Returns: This channel
/**
     * Binds the channel's socket to a local address.
     *
     * <P> This method is used to establish a relationship between the socket
     * and the local addresses. Once a relationship is established then
     * the socket remains bound until the channel is closed. This relationship
     * may not necesssarily be with the address {@code local} as it may be removed
     * by {@link #unbindAddress unbindAddress}, but there will always be at least
     * one local address bound to the channel's socket once an invocation of
     * this method successfully completes.
     *
     * <P> Once the channel's socket has been successfully bound to a specific
     * address, that is not automatically assigned, more addresses
     * may be bound to it using {@link #bindAddress bindAddress}, or removed
     * using {@link #unbindAddress unbindAddress}.
     *
     * @param  local
     *         The local address to bind the socket, or {@code null} to
     *         bind the socket to an automatically assigned socket address
     *
     * @return  This channel
     *
     * @throws  java.nio.channels.AlreadyConnectedException
     *          If this channel is already connected
     *
     * @throws  java.nio.channels.ClosedChannelException
     *          If this channel is closed
     *
     * @throws  java.nio.channels.ConnectionPendingException
     *          If a non-blocking connection operation is already in progress on this channel
     *
     * @throws  java.nio.channels.AlreadyBoundException
     *          If this channel is already bound
     *
     * @throws  java.nio.channels.UnsupportedAddressTypeException
     *          If the type of the given address is not supported
     *
     * @throws  IOException
     *          If some other I/O error occurs
     *
     * @throws  SecurityException
     *          If a security manager has been installed and its
     *          {@link SecurityManager#checkListen checkListen} method denies
     *          the operation
     */
    public abstract SctpChannel bind(SocketAddress local)
        throws IOException;

    
Adds the given address to the bound addresses for the channel's
socket.

 The given address must not be the wildcard address. The channel must be first bound using bind before invoking this method, otherwise NotYetBoundException is thrown. The bind method takes a SocketAddress as its argument which typically contains a port number as well as an address. Addresses subquently bound using this method are simply addresses as the SCTP port number remains the same for the lifetime of the channel. 
 Adding addresses to a connected association is optional functionality.
If the endpoint supports dynamic address reconfiguration then it may
send the appropriate message to the peer to change the peers address
lists.

Params:
  • address – 
        The address to add to the bound addresses for the socket
Throws:
Returns: This channel
/**
     * Adds the given address to the bound addresses for the channel's
     * socket.
     *
     * <P> The given address must not be the {@link
     * java.net.InetAddress#isAnyLocalAddress wildcard} address.
     * The channel must be first bound using {@link #bind bind} before
     * invoking this method, otherwise {@link
     * java.nio.channels.NotYetBoundException} is thrown. The {@link #bind bind}
     * method takes a {@code SocketAddress} as its argument which typically
     * contains a port number as well as an address. Addresses subquently bound
     * using this method are simply addresses as the SCTP port number remains
     * the same for the lifetime of the channel.
     *
     * <P> Adding addresses to a connected association is optional functionality.
     * If the endpoint supports dynamic address reconfiguration then it may
     * send the appropriate message to the peer to change the peers address
     * lists.
     *
     * @param  address
     *         The address to add to the bound addresses for the socket
     *
     * @return  This channel
     *
     * @throws  java.nio.channels.ClosedChannelException
     *          If this channel is closed
     *
     * @throws  java.nio.channels.ConnectionPendingException
     *          If a non-blocking connection operation is already in progress on
     *          this channel
     *
     * @throws  java.nio.channels.NotYetBoundException
     *          If this channel is not yet bound
     *
     * @throws  java.nio.channels.AlreadyBoundException
     *          If this channel is already bound to the given address
     *
     * @throws  IllegalArgumentException
     *          If address is {@code null} or the {@link
     *          java.net.InetAddress#isAnyLocalAddress wildcard} address
     *
     * @throws  IOException
     *          If some other I/O error occurs
     */
    public abstract SctpChannel bindAddress(InetAddress address)
         throws IOException;

    
Removes the given address from the bound addresses for the channel's
socket.

 The given address must not be the wildcard address. The channel must be first bound using bind before invoking this method, otherwise NotYetBoundException is thrown. If this method is invoked on a channel that does not have address as one of its bound addresses or that has only one local address bound to it, then this method throws IllegalUnbindException. The initial address that the channel's socket is bound to using bind may be removed from the bound addresses for the channel's socket. 
 Removing addresses from a connected association is optional
functionality. If the endpoint supports dynamic address reconfiguration
then it may send the appropriate message to the peer to change the peers
address lists.

Params:
  • address – 
        The address to remove from the bound addresses for the socket
Throws:
Returns: This channel
/**
     * Removes the given address from the bound addresses for the channel's
     * socket.
     *
     * <P> The given address must not be the {@link
     * java.net.InetAddress#isAnyLocalAddress wildcard} address.
     * The channel must be first bound using {@link #bind bind} before
     * invoking this method, otherwise {@link java.nio.channels.NotYetBoundException}
     * is thrown. If this method is invoked on a channel that does not have
     * {@code address} as one of its bound addresses or that has only one
     * local address bound to it, then this method throws
     * {@link IllegalUnbindException}.
     * The initial address that the channel's socket is bound to using {@link
     * #bind bind} may be removed from the bound addresses for the channel's socket.
     *
     * <P> Removing addresses from a connected association is optional
     * functionality. If the endpoint supports dynamic address reconfiguration
     * then it may send the appropriate message to the peer to change the peers
     * address lists.
     *
     * @param  address
     *         The address to remove from the bound addresses for the socket
     *
     * @return  This channel
     *
     * @throws  java.nio.channels.ClosedChannelException
     *          If this channel is closed
     *
     * @throws  java.nio.channels.ConnectionPendingException
     *          If a non-blocking connection operation is already in progress on
     *          this channel
     *
     * @throws  java.nio.channels.NotYetBoundException
     *          If this channel is not yet bound
     *
     * @throws  IllegalArgumentException
     *          If address is {@code null} or the {@link
     *          java.net.InetAddress#isAnyLocalAddress wildcard} address
     *
     * @throws  IllegalUnbindException
     *          If {@code address} is not bound to the channel's socket. or
     *          the channel has only one address bound to it
     *
     * @throws  IOException
     *          If some other I/O error occurs
     */
    public abstract SctpChannel unbindAddress(InetAddress address)
         throws IOException;

    
Connects this channel's socket.

 If this channel is in non-blocking mode then an invocation of this method initiates a non-blocking connection operation. If the connection is established immediately, as can happen with a local connection, then this method returns true. Otherwise this method returns false and the connection operation must later be completed by invoking the finishConnect method. 
 If this channel is in blocking mode then an invocation of this
method will block until the connection is established or an I/O error
occurs.

 If a security manager has been installed then this method verifies that its checkConnect method permits connecting to the address and port number of the given remote peer. 
 This method may be invoked at any time. If a send or receive operation upon this channel is invoked while an invocation of this method is in progress then that operation will first block until this invocation is complete. If a connection attempt is initiated but fails, that is, if an invocation of this method throws a checked exception, then the channel will be closed. 
Params:
  • remote – 
        The remote peer to which this channel is to be connected
Throws:
Returns: true if a connection was established, false if this channel is in non-blocking mode and the connection operation is in progress
/**
     * Connects this channel's socket.
     *
     * <P> If this channel is in non-blocking mode then an invocation of this
     * method initiates a non-blocking connection operation.  If the connection
     * is established immediately, as can happen with a local connection, then
     * this method returns {@code true}.  Otherwise this method returns
     * {@code false} and the connection operation must later be completed by
     * invoking the {@link #finishConnect finishConnect} method.
     *
     * <P> If this channel is in blocking mode then an invocation of this
     * method will block until the connection is established or an I/O error
     * occurs.
     *
     * <P> If a security manager has been installed then this method verifies
     * that its {@link java.lang.SecurityManager#checkConnect checkConnect}
     * method permits connecting to the address and port number of the given
     * remote peer.
     *
     * <p> This method may be invoked at any time. If a {@link #send send} or
     * {@link #receive receive} operation upon this channel is invoked while an
     * invocation of this method is in progress then that operation will first
     * block until this invocation is complete.  If a connection attempt is
     * initiated but fails, that is, if an invocation of this method throws a
     * checked exception, then the channel will be closed.
     *
     * @param  remote
     *         The remote peer to which this channel is to be connected
     *
     * @return  {@code true} if a connection was established, {@code false} if
     *          this channel is in non-blocking mode and the connection
     *          operation is in progress
     *
     * @throws  java.nio.channels.AlreadyConnectedException
     *          If this channel is already connected
     *
     * @throws  java.nio.channels.ConnectionPendingException
     *          If a non-blocking connection operation is already in progress on
     *          this channel
     *
     * @throws  java.nio.channels.ClosedChannelException
     *          If this channel is closed
     *
     * @throws  java.nio.channels.AsynchronousCloseException
     *          If another thread closes this channel
     *          while the connect operation is in progress
     *
     * @throws  java.nio.channels.ClosedByInterruptException
     *          If another thread interrupts the current thread
     *          while the connect operation is in progress, thereby
     *          closing the channel and setting the current thread's
     *          interrupt status
     *
     * @throws  java.nio.channels.UnresolvedAddressException
     *          If the given remote address is not fully resolved
     *
     * @throws  java.nio.channels.UnsupportedAddressTypeException
     *          If the type of the given remote address is not supported
     *
     * @throws  SecurityException
     *          If a security manager has been installed
     *          and it does not permit access to the given remote peer
     *
     * @throws  IOException
     *          If some other I/O error occurs
     */
    public abstract boolean connect(SocketAddress remote) throws IOException;

    
Connects this channel's socket.

 This is a convience method and is equivalent to evaluating the
following expression:

setOption(SctpStandardSocketOptions.SCTP_INIT_MAXSTREAMS, SctpStandardSocketOption.InitMaxStreams.create(maxInStreams, maxOutStreams))
 .connect(remote);



 The maxOutStreams and maxInStreams parameters represent the maximum number of streams that the application wishes to be able to send to and receive from. They are negotiated with the remote peer and may be limited by the operating system. 
Params:
  • remote – 
        The remote peer to which this channel is to be connected
  • maxOutStreams –  Must be non negative and no larger than 65536. 0 to use the endpoints default value.
  • maxInStreams –  Must be non negative and no larger than 65536. 0 to use the endpoints default value.
Throws:
Returns: true if a connection was established, false if this channel is in non-blocking mode and the connection operation is in progress
/**
     * Connects this channel's socket.
     *
     * <P> This is a convience method and is equivalent to evaluating the
     * following expression:
     * <blockquote><pre>
     * setOption(SctpStandardSocketOptions.SCTP_INIT_MAXSTREAMS, SctpStandardSocketOption.InitMaxStreams.create(maxInStreams, maxOutStreams))
     *  .connect(remote);
     * </pre></blockquote>
     *
     * <P> The {@code maxOutStreams} and {@code maxInStreams} parameters
     * represent the maximum number of streams that the application wishes to be
     * able to send to and receive from. They are negotiated with the remote
     * peer and may be limited by the operating system.
     *
     * @param  remote
     *         The remote peer to which this channel is to be connected
     *
     * @param  maxOutStreams
     *         Must be non negative and no larger than {@code 65536}.
     *         {@code 0} to use the endpoints default value.
     *
     * @param  maxInStreams
     *         Must be non negative and no larger than {@code 65536}.
     *         {@code 0} to use the endpoints default value.
     *
     * @return  {@code true} if a connection was established, {@code false} if
     *          this channel is in non-blocking mode and the connection operation
     *          is in progress
     *
     * @throws  java.nio.channels.AlreadyConnectedException
     *          If this channel is already connected
     *
     * @throws  java.nio.channels.ConnectionPendingException
     *          If a non-blocking connection operation is already in progress on
     *          this channel
     *
     * @throws  java.nio.channels.ClosedChannelException
     *          If this channel is closed
     *
     * @throws  java.nio.channels.AsynchronousCloseException
     *          If another thread closes this channel
     *          while the connect operation is in progress
     *
     * @throws  java.nio.channels.ClosedByInterruptException
     *          If another thread interrupts the current thread
     *          while the connect operation is in progress, thereby
     *          closing the channel and setting the current thread's
     *          interrupt status
     *
     * @throws  java.nio.channels.UnresolvedAddressException
     *          If the given remote address is not fully resolved
     *
     * @throws  java.nio.channels.UnsupportedAddressTypeException
     *          If the type of the given remote address is not supported
     *
     * @throws  SecurityException
     *          If a security manager has been installed
     *          and it does not permit access to the given remote peer
     *
     * @throws  IOException
     *          If some other I/O error occurs
     */
    public abstract boolean connect(SocketAddress remote,
                                    int maxOutStreams,
                                    int maxInStreams)
        throws IOException;

    
Tells whether or not a connection operation is in progress on this channel.

Returns: true if, and only if, a connection operation has been initiated on this channel but not yet completed by invoking the finishConnect method
/**
     * Tells whether or not a connection operation is in progress on this channel.
     *
     * @return  {@code true} if, and only if, a connection operation has been initiated
     *          on this channel but not yet completed by invoking the
     *          {@link #finishConnect} method
     */
    public abstract boolean isConnectionPending();

    
Finishes the process of connecting an SCTP channel.

 A non-blocking connection operation is initiated by placing a socket channel in non-blocking mode and then invoking one of its 
connect methods. Once the connection is established, or the attempt has failed, the channel will become connectable and this method may be invoked to complete the connection sequence. If the connection operation failed then invoking this method will cause an appropriate IOException to be thrown. 
 If this channel is already connected then this method will not block and will immediately return true. If this channel is in non-blocking mode then this method will return false if the connection process is not yet complete. If this channel is in blocking mode then this method will block until the connection either completes or fails, and will always either return true or throw a checked exception describing the failure. 
 This method may be invoked at any time. If a send or receive operation upon this channel is invoked while an invocation of this method is in progress then that operation will first block until this invocation is complete. If a connection attempt fails, that is, if an invocation of this method throws a checked exception, then the channel will be closed. 
Throws:
Returns: true if, and only if, this channel's socket is now connected
/**
     * Finishes the process of connecting an SCTP channel.
     *
     * <P> A non-blocking connection operation is initiated by placing a socket
     * channel in non-blocking mode and then invoking one of its {@link #connect
     * connect} methods.  Once the connection is established, or the attempt has
     * failed, the channel will become connectable and this method may
     * be invoked to complete the connection sequence.  If the connection
     * operation failed then invoking this method will cause an appropriate
     * {@link java.io.IOException} to be thrown.
     *
     * <P> If this channel is already connected then this method will not block
     * and will immediately return {@code true}.  If this channel is in
     * non-blocking mode then this method will return {@code false} if the
     * connection process is not yet complete.  If this channel is in blocking
     * mode then this method will block until the connection either completes
     * or fails, and will always either return {@code true} or throw a checked
     * exception describing the failure.
     *
     * <P> This method may be invoked at any time. If a {@link #send send} or {@link #receive receive}
     * operation upon this channel is invoked while an invocation of this
     * method is in progress then that operation will first block until this
     * invocation is complete.  If a connection attempt fails, that is, if an
     * invocation of this method throws a checked exception, then the channel
     * will be closed.
     *
     * @return  {@code true} if, and only if, this channel's socket is now
     *          connected
     *
     * @throws  java.nio.channels.NoConnectionPendingException
     *          If this channel is not connected and a connection operation
     *          has not been initiated
     *
     * @throws  java.nio.channels.ClosedChannelException
     *          If this channel is closed
     *
     * @throws  java.nio.channels.AsynchronousCloseException
     *          If another thread closes this channel
     *          while the connect operation is in progress
     *
     * @throws  java.nio.channels.ClosedByInterruptException
     *          If another thread interrupts the current thread
     *          while the connect operation is in progress, thereby
     *          closing the channel and setting the current thread's
     *          interrupt status
     *
     * @throws  IOException
     *          If some other I/O error occurs
     */
    public abstract boolean finishConnect() throws IOException;

    
Returns all of the socket addresses to which this channel's socket is
bound.

Throws:
Returns: All the socket addresses that this channel's socket is bound to, or an empty Set if the channel's socket is not bound
/**
     * Returns all of the socket addresses to which this channel's socket is
     * bound.
     *
     * @return  All the socket addresses that this channel's socket is
     *          bound to, or an empty {@code Set} if the channel's socket is not
     *          bound
     *
     * @throws  ClosedChannelException
     *          If the channel is closed
     *
     * @throws  IOException
     *          If an I/O error occurs
     */
    public abstract Set<SocketAddress> getAllLocalAddresses()
        throws IOException;

    
Returns all of the remote addresses to which this channel's socket
is connected.

 If the channel is connected to a remote peer that is bound to
multiple addresses then it is these addresses that the channel's socket
is connected.

Throws:
Returns: All of the remote addresses to which this channel's socket is connected, or an empty Set if the channel's socket is not connected
/**
     * Returns all of the remote addresses to which this channel's socket
     * is connected.
     *
     * <P> If the channel is connected to a remote peer that is bound to
     * multiple addresses then it is these addresses that the channel's socket
     * is connected.
     *
     * @return  All of the remote addresses to which this channel's socket
     *          is connected, or an empty {@code Set} if the channel's socket is
     *          not connected
     *
     * @throws  ClosedChannelException
     *          If the channel is closed
     *
     * @throws  IOException
     *          If an I/O error occurs
     */
    public abstract Set<SocketAddress> getRemoteAddresses()
        throws IOException;

    
Shutdown a connection without closing the channel.

 Sends a shutdown command to the remote peer, effectively preventing any new data from being written to the socket by either peer. Further sends will throw ClosedChannelException. The channel remains open to allow the for any data (and notifications) to be received that may have been sent by the peer before it received the shutdown command. If the channel is already shutdown then invoking this method has no effect. 
Throws:
Returns: This channel
/**
     * Shutdown a connection without closing the channel.
     *
     * <P> Sends a shutdown command to the remote peer, effectively preventing
     * any new data from being written to the socket by either peer. Further
     * sends will throw {@link java.nio.channels.ClosedChannelException}. The
     * channel remains open to allow the for any data (and notifications) to be
     * received that may have been sent by the peer before it received the
     * shutdown command. If the channel is already shutdown then invoking this
     * method has no effect.
     *
     * @return  This channel
     *
     * @throws  java.nio.channels.NotYetConnectedException
     *          If this channel is not yet connected
     *
     * @throws  java.nio.channels.ClosedChannelException
     *          If this channel is closed
     *
     * @throws  IOException
     *          If some other I/O error occurs
     */
    public abstract SctpChannel shutdown() throws IOException;

    
Returns the value of a socket option.

Params:
  • name – 
         The socket option
Type parameters:
  • <T> – 
         The type of the socket option value
Throws:
See Also:
Returns: The value of the socket option. A value of null may be a valid value for some socket options.
/**
     * Returns the value of a socket option.
     *
     * @param   <T>
     *          The type of the socket option value
     *
     * @param   name
     *          The socket option
     *
     * @return  The value of the socket option. A value of {@code null} may be
     *          a valid value for some socket options.
     *
     * @throws  UnsupportedOperationException
     *          If the socket option is not supported by this channel
     *
     * @throws  ClosedChannelException
     *          If this channel is closed
     *
     * @throws  IOException
     *          If an I/O error occurs
     *
     * @see SctpStandardSocketOptions
     */
    public abstract <T> T getOption(SctpSocketOption<T> name)
        throws IOException;

    
Sets the value of a socket option.

Params:
  • name – 
         The socket option
  • value –  The value of the socket option. A value of null may be a valid value for some socket options.
Type parameters:
  • <T> – 
         The type of the socket option value
Throws:
See Also:
Returns: This channel
/**
     * Sets the value of a socket option.
     *
     * @param   <T>
     *          The type of the socket option value
     *
     * @param   name
     *          The socket option
     *
     * @param   value
     *          The value of the socket option. A value of {@code null} may be
     *          a valid value for some socket options.
     *
     * @return  This channel
     *
     * @throws  UnsupportedOperationException
     *          If the socket option is not supported by this channel
     *
     * @throws  IllegalArgumentException
     *          If the value is not a valid value for this socket option
     *
     * @throws  ClosedChannelException
     *          If this channel is closed
     *
     * @throws  IOException
     *          If an I/O error occurs
     *
     * @see SctpStandardSocketOptions
     */
    public abstract <T> SctpChannel setOption(SctpSocketOption<T> name, T value)
        throws IOException;

    
Returns a set of the socket options supported by this channel.

 This method will continue to return the set of options even after the
channel has been closed.

Returns: A set of the socket options supported by this channel
/**
     * Returns a set of the socket options supported by this channel.
     *
     * <P> This method will continue to return the set of options even after the
     * channel has been closed.
     *
     * @return  A set of the socket options supported by this channel
     */
    public abstract Set<SctpSocketOption<?>> supportedOptions();

    
Returns an operation set identifying this channel's supported operations.

 SCTP channels support connecting, reading, and writing, so this method returns (SelectionKey.OP_CONNECT | SelectionKey.OP_READ | SelectionKey.OP_WRITE). 
Returns: The valid-operation set
/**
     * Returns an operation set identifying this channel's supported operations.
     *
     * <P> SCTP channels support connecting, reading, and writing, so this
     * method returns {@code (}{@link SelectionKey#OP_CONNECT}
     * {@code |}&nbsp;{@link SelectionKey#OP_READ} {@code |}&nbsp;{@link
     * SelectionKey#OP_WRITE}{@code )}.
     *
     * @return  The valid-operation set
     */
    @Override
    public final int validOps() {
        return (SelectionKey.OP_READ |
                SelectionKey.OP_WRITE |
                SelectionKey.OP_CONNECT);
    }

    
Receives a message into the given buffer and/or handles a notification.

 If a message or notification is immediately available, or if this channel is in blocking mode and one eventually becomes available, then the message or notification is returned or handled, respectively. If this channel is in non-blocking mode and a message or notification is not immediately available then this method immediately returns null. 
 If this method receives a message it is copied into the given byte buffer. The message is transferred into the given byte buffer starting at its current position and the buffers position is incremented by the number of bytes read. If there are fewer bytes remaining in the buffer than are required to hold the message, or the underlying input buffer does not contain the complete message, then an invocation of isComplete on the returned 
MessageInfo will return false, and more invocations of this method will be necessary to completely consume the messgae. Only one message at a time will be partially delivered in any stream. The socket option 
SCTP_FRAGMENT_INTERLEAVE controls various aspects of what interlacing of messages occurs. 
 If this method receives a notification then the appropriate method of the given handler, if there is one, is invoked. If the handler returns CONTINUE then this method will try to receive another message/notification, otherwise, if RETURN is returned this method will return 
null. If an uncaught exception is thrown by the handler it will be propagated up the stack through this method. 
 This method may be invoked at any time. If another thread has already initiated a receive operation upon this channel, then an invocation of this method will block until the first operation is complete. The given handler is invoked without holding any locks used to enforce the above synchronization policy, that way handlers will not stall other threads from receiving. A handler should not invoke the receive method of this channel, if it does an IllegalReceiveException will be thrown. 
Params:
  • dst – 
        The buffer into which message bytes are to be transferred
  • attachment –  The object to attach to the receive operation; can be null
  • handler –  A handler to handle notifications from the SCTP stack, or 
        null to ignore any notifications.
Type parameters:
  • <T> – 
        The type of the attachment
Throws:
Returns: The MessageInfo, null if this channel is in non-blocking mode and no messages are immediately available or the notification handler returns 
         RETURN after handling a notification
/**
     * Receives a message into the given buffer and/or handles a notification.
     *
     * <P> If a message or notification is immediately available, or if this
     * channel is in blocking mode and one eventually becomes available, then
     * the message or notification is returned or handled, respectively. If this
     * channel is in non-blocking mode and a message or notification is not
     * immediately available then this method immediately returns {@code null}.
     *
     * <P> If this method receives a message it is copied into the given byte
     * buffer. The message is transferred into the given byte buffer starting at
     * its current position and the buffers position is incremented by the
     * number of bytes read. If there are fewer bytes remaining in the buffer
     * than are required to hold the message, or the underlying input buffer
     * does not contain the complete message, then an invocation of {@link
     * MessageInfo#isComplete isComplete} on the returned {@code
     * MessageInfo} will return {@code false}, and more invocations of this
     * method will be necessary to completely consume the messgae. Only
     * one message at a time will be partially delivered in any stream. The
     * socket option {@link SctpStandardSocketOptions#SCTP_FRAGMENT_INTERLEAVE
     * SCTP_FRAGMENT_INTERLEAVE} controls various aspects of what interlacing of
     * messages occurs.
     *
     * <P> If this method receives a notification then the appropriate method of
     * the given handler, if there is one, is invoked. If the handler returns
     * {@link HandlerResult#CONTINUE CONTINUE} then this method will try to
     * receive another message/notification, otherwise, if {@link
     * HandlerResult#RETURN RETURN} is returned this method will return {@code
     * null}. If an uncaught exception is thrown by the handler it will be
     * propagated up the stack through this method.
     *
     * <P> This method may be invoked at any time. If another thread has
     * already initiated a receive operation upon this channel, then an
     * invocation of this method will block until the first operation is
     * complete. The given handler is invoked without holding any locks used
     * to enforce the above synchronization policy, that way handlers
     * will not stall other threads from receiving. A handler should not invoke
     * the {@code receive} method of this channel, if it does an
     * {@link IllegalReceiveException} will be thrown.
     *
     * @param  <T>
     *         The type of the attachment
     *
     * @param  dst
     *         The buffer into which message bytes are to be transferred
     *
     * @param  attachment
     *         The object to attach to the receive operation; can be
     *         {@code null}
     *
     * @param  handler
     *         A handler to handle notifications from the SCTP stack, or {@code
     *         null} to ignore any notifications.
     *
     * @return  The {@code MessageInfo}, {@code null} if this channel is in
     *          non-blocking mode and no messages are immediately available or
     *          the notification handler returns {@link HandlerResult#RETURN
     *          RETURN} after handling a notification
     *
     * @throws  java.nio.channels.ClosedChannelException
     *          If this channel is closed
     *
     * @throws  java.nio.channels.AsynchronousCloseException
     *          If another thread closes this channel
     *          while the read operation is in progress
     *
     * @throws  java.nio.channels.ClosedByInterruptException
     *          If another thread interrupts the current thread
     *          while the read operation is in progress, thereby
     *          closing the channel and setting the current thread's
     *          interrupt status
     *
     * @throws  java.nio.channels.NotYetConnectedException
     *          If this channel is not yet connected
     *
     * @throws  IllegalReceiveException
     *          If the given handler invokes the {@code receive} method of this
     *          channel
     *
     * @throws  IOException
     *          If some other I/O error occurs
     */
    public abstract <T> MessageInfo receive(ByteBuffer dst,
                                            T attachment,
                                            NotificationHandler<T> handler)
        throws IOException;

    
Sends a message via this channel.

 If this channel is in non-blocking mode and there is sufficient room in the underlying output buffer, or if this channel is in blocking mode and sufficient room becomes available, then the remaining bytes in the given byte buffer are transmitted as a single message. Sending a message is atomic unless explicit message completion SCTP_EXPLICIT_COMPLETE socket option is enabled on this channel's socket. 
 The message is transferred from the byte buffer as if by a regular 
write operation. 
 The bytes will be written to the stream number that is specified by streamNumber in the given 
messageInfo. 
 This method may be invoked at any time. If another thread has already
initiated a send operation upon this channel, then an invocation of
this method will block until the first operation is complete.

Params:
  • src – 
        The buffer containing the message to be sent
  • messageInfo – 
        Ancillary data about the message to be sent
Throws:
Returns: The number of bytes sent, which will be either the number of
         bytes that were remaining in the messages buffer when this method
         was invoked or, if this channel is non-blocking, may be zero if
         there was insufficient room for the message in the underlying
         output buffer
/**
     * Sends a message via this channel.
     *
     * <P> If this channel is in non-blocking mode and there is sufficient room
     * in the underlying output buffer, or if this channel is in blocking mode
     * and sufficient room becomes available, then the remaining bytes in the
     * given byte buffer are transmitted as a single message. Sending a message
     * is atomic unless explicit message completion {@link
     * SctpStandardSocketOptions#SCTP_EXPLICIT_COMPLETE SCTP_EXPLICIT_COMPLETE}
     * socket option is enabled on this channel's socket.
     *
     * <P> The message is transferred from the byte buffer as if by a regular
     * {@link java.nio.channels.WritableByteChannel#write(java.nio.ByteBuffer)
     * write} operation.
     *
     * <P> The bytes will be written to the stream number that is specified by
     * {@link MessageInfo#streamNumber streamNumber} in the given {@code
     * messageInfo}.
     *
     * <P> This method may be invoked at any time. If another thread has already
     * initiated a send operation upon this channel, then an invocation of
     * this method will block until the first operation is complete.
     *
     * @param  src
     *         The buffer containing the message to be sent
     *
     * @param  messageInfo
     *         Ancillary data about the message to be sent
     *
     * @return  The number of bytes sent, which will be either the number of
     *          bytes that were remaining in the messages buffer when this method
     *          was invoked or, if this channel is non-blocking, may be zero if
     *          there was insufficient room for the message in the underlying
     *          output buffer
     *
     * @throws  InvalidStreamException
     *          If {@code streamNumner} is negative or greater than or equal to
     *          the maximum number of outgoing streams
     *
     * @throws  java.nio.channels.ClosedChannelException
     *          If this channel is closed
     *
     * @throws  java.nio.channels.AsynchronousCloseException
     *          If another thread closes this channel
     *          while the read operation is in progress
     *
     * @throws  java.nio.channels.ClosedByInterruptException
     *          If another thread interrupts the current thread
     *          while the read operation is in progress, thereby
     *          closing the channel and setting the current thread's
     *          interrupt status
     *
     * @throws  java.nio.channels.NotYetConnectedException
     *          If this channel is not yet connected
     *
     * @throws  IOException
     *          If some other I/O error occurs
     */
    public abstract int send(ByteBuffer src, MessageInfo messageInfo)
        throws IOException;
}