/*
* Copyright (c) 2009, 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,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* 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.
*
* <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 border>
* <tr>
* <th>Option Name</th>
* <th>Description</th>
* </tr>
* <tr>
* <td> {@link SctpStandardSocketOptions#SCTP_DISABLE_FRAGMENTS
* SCTP_DISABLE_FRAGMENTS} </td>
* <td> Enables or disables message fragmentation </td>
* </tr>
* <tr>
* <td> {@link SctpStandardSocketOptions#SCTP_EXPLICIT_COMPLETE
* SCTP_EXPLICIT_COMPLETE} </td>
* <td> Enables or disables explicit message completion </td>
* </tr>
* <tr>
* <td> {@link SctpStandardSocketOptions#SCTP_FRAGMENT_INTERLEAVE
* SCTP_FRAGMENT_INTERLEAVE} </td>
* <td> Controls how the presentation of messages occur for the message
* receiver </td>
* </tr>
* <tr>
* <td> {@link SctpStandardSocketOptions#SCTP_INIT_MAXSTREAMS
* SCTP_INIT_MAXSTREAMS} </td>
* <td> The maximum number of streams requested by the local endpoint during
* association initialization </td>
* </tr>
* <tr>
* <td> {@link SctpStandardSocketOptions#SCTP_NODELAY SCTP_NODELAY} </td>
* <td> Enables or disable a Nagle-like algorithm </td>
* </tr>
* <tr>
* <td> {@link SctpStandardSocketOptions#SCTP_PRIMARY_ADDR
* SCTP_PRIMARY_ADDR} </td>
* <td> Requests that the local SCTP stack use the given peer address as the
* association primary </td>
* </tr>
* <tr>
* <td> {@link SctpStandardSocketOptions#SCTP_SET_PEER_PRIMARY_ADDR
* SCTP_SET_PEER_PRIMARY_ADDR} </td>
* <td> Requests that the peer mark the enclosed address as the association
* primary </td>
* </tr>
* <tr>
* <td> {@link SctpStandardSocketOptions#SO_SNDBUF
* SO_SNDBUF} </td>
* <td> The size of the socket send buffer </td>
* </tr>
* <tr>
* <td> {@link SctpStandardSocketOptions#SO_RCVBUF
* SO_RCVBUF} </td>
* <td> The size of the socket receive buffer </td>
* </tr>
* <tr>
* <td> {@link SctpStandardSocketOptions#SO_LINGER
* SO_LINGER} </td>
* <td> Linger on close if data is present (when configured in blocking mode
* only) </td>
* </tr>
* </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.
*
* @param provider
* The selector provider for this channel
*/
protected SctpChannel(SelectorProvider provider) {
super(provider);
}
/**
* 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.SctpChannelImpl((SelectorProvider)null);
}
/**
* 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.
*
* @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.
*
* <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
*/
public abstract SctpChannel bind(SocketAddress local)
throws IOException;
/**
* 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.
*
* <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.
*
* <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.
*
* <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.
*
* @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.
*
* <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 <tt>true</tt>. If this channel is in
* non-blocking mode then this method will return <tt>false</tt> 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 <tt>true</tt> 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.
*
* @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.
*
* <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.
*
* <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.
*
* @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.
*
* @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.
*
* <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.
*
* <P> SCTP channels support connecting, reading, and writing, so this
* method returns <tt>(</tt>{@link SelectionKey#OP_CONNECT}
* <tt>|</tt>&nbsp;{@link SelectionKey#OP_READ} <tt>|</tt>&nbsp;{@link
* SelectionKey#OP_WRITE}<tt>)</tt>. </p>
*
* @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.
*
* <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 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.
*
* <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 InvalidStreamExcepton
* 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;
}