@Exported public abstract class SctpChannel extends AbstractSelectableChannel
 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:
 
Additional (implementation specific) options may also be supported. The list of options supported is obtained by invoking the
Option Name Description SCTP_DISABLE_FRAGMENTSEnables or disables message fragmentation SCTP_EXPLICIT_COMPLETEEnables or disables explicit message completion SCTP_FRAGMENT_INTERLEAVEControls how the presentation of messages occur for the message receiver SCTP_INIT_MAXSTREAMSThe maximum number of streams requested by the local endpoint during association initialization SCTP_NODELAYEnables or disable a Nagle-like algorithm SCTP_PRIMARY_ADDRRequests that the local SCTP stack use the given peer address as the association primary SCTP_SET_PEER_PRIMARY_ADDRRequests that the peer mark the enclosed address as the association primary SO_SNDBUFThe size of the socket send buffer SO_RCVBUFThe size of the socket receive buffer SO_LINGERLinger on close if data is present (when configured in blocking mode only) 
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.
| Modifier | Constructor and Description | 
|---|---|
| protected  | SctpChannel(SelectorProvider provider)Initializes a new instance of this class. | 
| Modifier and Type | Method and Description | 
|---|---|
| abstract Association | association()Returns the association on this channel's socket. | 
| abstract SctpChannel | bind(SocketAddress local)Binds the channel's socket to a local address. | 
| abstract SctpChannel | bindAddress(InetAddress address)Adds the given address to the bound addresses for the channel's
 socket. | 
| abstract boolean | connect(SocketAddress remote)Connects this channel's socket. | 
| abstract boolean | connect(SocketAddress remote,
       int maxOutStreams,
       int maxInStreams)Connects this channel's socket. | 
| abstract boolean | finishConnect()Finishes the process of connecting an SCTP channel. | 
| abstract Set<SocketAddress> | getAllLocalAddresses()Returns all of the socket addresses to which this channel's socket is
 bound. | 
| abstract <T> T | getOption(SctpSocketOption<T> name)Returns the value of a socket option. | 
| abstract Set<SocketAddress> | getRemoteAddresses()Returns all of the remote addresses to which this channel's socket
 is connected. | 
| abstract boolean | isConnectionPending()Tells whether or not a connection operation is in progress on this channel. | 
| static SctpChannel | open()Opens an SCTP channel. | 
| static SctpChannel | open(SocketAddress remote,
    int maxOutStreams,
    int maxInStreams)Opens an SCTP channel and connects it to a remote address. | 
| abstract <T> MessageInfo | receive(ByteBuffer dst,
       T attachment,
       NotificationHandler<T> handler)Receives a message into the given buffer and/or handles a notification. | 
| abstract int | send(ByteBuffer src,
    MessageInfo messageInfo)Sends a message via this channel. | 
| abstract <T> SctpChannel | setOption(SctpSocketOption<T> name,
         T value)Sets the value of a socket option. | 
| abstract SctpChannel | shutdown()Shutdown a connection without closing the channel. | 
| abstract Set<SctpSocketOption<?>> | supportedOptions()Returns a set of the socket options supported by this channel. | 
| abstract SctpChannel | unbindAddress(InetAddress address)Removes the given address from the bound addresses for the channel's
 socket. | 
| int | validOps()Returns an operation set identifying this channel's supported operations. | 
blockingLock, configureBlocking, implCloseChannel, implCloseSelectableChannel, implConfigureBlocking, isBlocking, isRegistered, keyFor, provider, registerregisterbegin, close, end, isOpenprotected SctpChannel(SelectorProvider provider)
provider - The selector provider for this channelpublic static SctpChannel open() throws IOException
The new channel is unbound and unconnected.
UnsupportedOperationException - If the SCTP protocol is not supportedIOException - If an I/O error occurspublic static SctpChannel open(SocketAddress remote, int maxOutStreams, int maxInStreams) throws IOException
This is a convenience method and is equivalent to evaluating the following expression:
open().connect(remote, maxOutStreams, maxInStreams);
remote - The remote address to which the new channel is to be connectedmaxOutStreams - 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.AsynchronousCloseException - If another thread closes this channel
          while the connect operation is in progressClosedByInterruptException - 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 statusUnresolvedAddressException - If the given remote address is not fully resolvedUnsupportedAddressTypeException - If the type of the given remote address is not supportedSecurityException - If a security manager has been installed
          and it does not permit access to the given remote peerUnsupportedOperationException - If the SCTP protocol is not supportedIOException - If some other I/O error occurspublic abstract Association association() throws IOException
null if the channel's socket is not
          connected.ClosedChannelException - If the channel is closedIOException - If some other I/O error occurspublic abstract SctpChannel bind(SocketAddress local) throws IOException
 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.
local - The local address to bind the socket, or null to
         bind the socket to an automatically assigned socket addressAlreadyConnectedException - If this channel is already connectedClosedChannelException - If this channel is closedConnectionPendingException - If a non-blocking connection operation is already in progress on this channelAlreadyBoundException - If this channel is already boundUnsupportedAddressTypeException - If the type of the given address is not supportedIOException - If some other I/O error occursSecurityException - If a security manager has been installed and its
          checkListen method denies
          the operationpublic abstract SctpChannel bindAddress(InetAddress address) throws IOException
 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.
address - The address to add to the bound addresses for the socketClosedChannelException - If this channel is closedConnectionPendingException - If a non-blocking connection operation is already in progress on
          this channelNotYetBoundException - If this channel is not yet boundAlreadyBoundException - If this channel is already bound to the given addressIllegalArgumentException - If address is null or the wildcard addressIOException - If some other I/O error occurspublic abstract SctpChannel unbindAddress(InetAddress address) throws IOException
 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.
address - The address to remove from the bound addresses for the socketClosedChannelException - If this channel is closedConnectionPendingException - If a non-blocking connection operation is already in progress on
          this channelNotYetBoundException - If this channel is not yet boundIllegalArgumentException - If address is null or the wildcard addressIllegalUnbindException - If address is not bound to the channel's socket. or
          the channel has only one address bound to itIOException - If some other I/O error occurspublic abstract boolean connect(SocketAddress remote) throws IOException
 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.
remote - The remote peer to which this channel is to be connectedtrue if a connection was established, false if
          this channel is in non-blocking mode and the connection
          operation is in progressAlreadyConnectedException - If this channel is already connectedConnectionPendingException - If a non-blocking connection operation is already in progress on
          this channelClosedChannelException - If this channel is closedAsynchronousCloseException - If another thread closes this channel
          while the connect operation is in progressClosedByInterruptException - 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 statusUnresolvedAddressException - If the given remote address is not fully resolvedUnsupportedAddressTypeException - If the type of the given remote address is not supportedSecurityException - If a security manager has been installed
          and it does not permit access to the given remote peerIOException - If some other I/O error occurspublic abstract boolean connect(SocketAddress remote, int maxOutStreams, int maxInStreams) throws IOException
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.
remote - The remote peer to which this channel is to be connectedmaxOutStreams - 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.true if a connection was established, false if
          this channel is in non-blocking mode and the connection operation
          is in progressAlreadyConnectedException - If this channel is already connectedConnectionPendingException - If a non-blocking connection operation is already in progress on
          this channelClosedChannelException - If this channel is closedAsynchronousCloseException - If another thread closes this channel
          while the connect operation is in progressClosedByInterruptException - 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 statusUnresolvedAddressException - If the given remote address is not fully resolvedUnsupportedAddressTypeException - If the type of the given remote address is not supportedSecurityException - If a security manager has been installed
          and it does not permit access to the given remote peerIOException - If some other I/O error occurspublic abstract boolean isConnectionPending()
true if, and only if, a connection operation has been initiated
          on this channel but not yet completed by invoking the
          finishConnect() methodpublic abstract boolean finishConnect()
                               throws IOException
 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.
true if, and only if, this channel's socket is now
          connectedNoConnectionPendingException - If this channel is not connected and a connection operation
          has not been initiatedClosedChannelException - If this channel is closedAsynchronousCloseException - If another thread closes this channel
          while the connect operation is in progressClosedByInterruptException - 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 statusIOException - If some other I/O error occurspublic abstract Set<SocketAddress> getAllLocalAddresses() throws IOException
Set if the channel's socket is not
          boundClosedChannelException - If the channel is closedIOException - If an I/O error occurspublic abstract Set<SocketAddress> getRemoteAddresses() throws IOException
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.
Set if the channel's socket is
          not connectedClosedChannelException - If the channel is closedIOException - If an I/O error occurspublic abstract SctpChannel shutdown() throws IOException
 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.
NotYetConnectedException - If this channel is not yet connectedClosedChannelException - If this channel is closedIOException - If some other I/O error occurspublic abstract <T> T getOption(SctpSocketOption<T> name) throws IOException
T - The type of the socket option valuename - The socket optionnull may be
          a valid value for some socket options.UnsupportedOperationException - If the socket option is not supported by this channelClosedChannelException - If this channel is closedIOException - If an I/O error occursSctpStandardSocketOptionspublic abstract <T> SctpChannel setOption(SctpSocketOption<T> name, T value) throws IOException
T - The type of the socket option valuename - The socket optionvalue - The value of the socket option. A value of null may be
          a valid value for some socket options.UnsupportedOperationException - If the socket option is not supported by this channelIllegalArgumentException - If the value is not a valid value for this socket optionClosedChannelException - If this channel is closedIOException - If an I/O error occursSctpStandardSocketOptionspublic abstract Set<SctpSocketOption<?>> supportedOptions()
This method will continue to return the set of options even after the channel has been closed.
public final int validOps()
 SCTP channels support connecting, reading, and writing, so this
 method returns (SelectionKey.OP_CONNECT
 | SelectionKey.OP_READ | SelectionKey.OP_WRITE).  
validOps in class SelectableChannelpublic abstract <T> MessageInfo receive(ByteBuffer dst, T attachment, NotificationHandler<T> handler) throws IOException
 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.
T - The type of the attachmentdst - The buffer into which message bytes are to be transferredattachment - The object to attach to the receive operation; can be
         nullhandler - A handler to handle notifications from the SCTP stack, or null to ignore any notifications.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 notificationClosedChannelException - If this channel is closedAsynchronousCloseException - If another thread closes this channel
          while the read operation is in progressClosedByInterruptException - 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 statusNotYetConnectedException - If this channel is not yet connectedIllegalReceiveException - If the given handler invokes the receive method of this
          channelIOException - If some other I/O error occurspublic abstract int send(ByteBuffer src, MessageInfo messageInfo) throws IOException
 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.
src - The buffer containing the message to be sentmessageInfo - Ancillary data about the message to be sentInvalidStreamException - If streamNumner is negative or greater than or equal to
          the maximum number of outgoing streamsClosedChannelException - If this channel is closedAsynchronousCloseException - If another thread closes this channel
          while the read operation is in progressClosedByInterruptException - 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 statusNotYetConnectedException - If this channel is not yet connectedIOException - If some other I/O error occurs
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