Class SctpServerChannel

com.sun.nio.sctp.SctpServerChannel

All Implemented Interfaces:: Closeable, AutoCloseable, Channel, InterruptibleChannel

public abstract class SctpServerChannel extends AbstractSelectableChannel

A selectable channel for message-oriented listening SCTP sockets.

An SCTPServerChannel is created by invoking the open method of this class. A newly-created SCTP server channel is open but not yet bound. An attempt to invoke the accept method of an unbound channel will cause the NotYetBoundException to be thrown. An SCTP server channel can be bound by invoking one of the bind methods defined by this class.

Socket options are configured using the setOption method. SCTP server socket channels support the following options:

Socket options

Option Name Description

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

Socket options
Option Name	Description
`SCTP_INIT_MAXSTREAMS`	The maximum number of streams requested by the local endpoint during association initialization

Additional (implementation specific) options may also be supported. The list of options supported is obtained by invoking the supportedOptions method.

SCTP server channels are safe for use by multiple concurrent threads.

Since:: 1.7

Constructor Summary

SctpServerChannel(SelectorProvider provider)

Modifier	Constructor	Description
`protected`	Initializes a new instance of this class.

Method Summary

Modifier and Type	Method	Description
`abstract SctpChannel`	`accept()`	Accepts an association on this channel's socket.
`final SctpServerChannel`	`bind(SocketAddress local)`	Binds the channel's socket to a local address and configures the socket to listen for associations.
`abstract SctpServerChannel`	`bind(SocketAddress local, int backlog)`	Binds the channel's socket to a local address and configures the socket to listen for associations.
`abstract SctpServerChannel`	`bindAddress(InetAddress address)`	Adds the given address to the bound addresses for the channel's socket.
`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.
`static SctpServerChannel`	`open()`	Opens an SCTP server channel.
`abstract <T> SctpServerChannel`	`setOption(SctpSocketOption<T> name, T value)`	Sets the value of a socket option.
`abstract Set<SctpSocketOption<?>>`	`supportedOptions()`	Returns a set of the socket options supported by this channel.
`abstract SctpServerChannel`	`unbindAddress(InetAddress address)`	Removes the given address from the bound addresses for the channel's socket.
`final int`	`validOps()`	Returns an operation set identifying this channel's supported operations.

Methods declared in class AbstractSelectableChannel

blockingLock, configureBlocking, implCloseChannel, implCloseSelectableChannel, implConfigureBlocking, isBlocking, isRegistered, keyFor, provider, register

Modifier and Type	Method	Description
`final Object`	`blockingLock()`	Retrieves the object upon which the `configureBlocking` and `register` methods synchronize.
`final SelectableChannel`	`configureBlocking(boolean block)`	Adjusts this channel's blocking mode.
`protected final void`	`implCloseChannel()`	Closes this channel.
`protected abstract void`	`implCloseSelectableChannel()`	Closes this selectable channel.
`protected abstract void`	`implConfigureBlocking(boolean block)`	Adjusts this channel's blocking mode.
`final boolean`	`isBlocking()`	Tells whether or not every I/O operation on this channel will block until it completes.
`final boolean`	`isRegistered()`	Tells whether or not this channel is currently registered with any selectors.
`final SelectionKey`	`keyFor(Selector sel)`	Retrieves the key representing the channel's registration with the given selector.
`final SelectorProvider`	`provider()`	Returns the provider that created this channel.
`final SelectionKey`	`register(Selector sel, int ops, Object att)`	Registers this channel with the given selector, returning a selection key.

Methods declared in class SelectableChannel

register

Modifier and Type	Method	Description
`final SelectionKey`	`register(Selector sel, int ops)`	Registers this channel with the given selector, returning a selection key.

Methods declared in class AbstractInterruptibleChannel

begin, close, end, isOpen

Modifier and Type	Method	Description
`protected final void`	`begin()`	Marks the beginning of an I/O operation that might block indefinitely.
`final void`	`close()`	Closes this channel.
`protected final void`	`end(boolean completed)`	Marks the end of an I/O operation that might block indefinitely.
`final boolean`	`isOpen()`	Tells whether or not this channel is open.

Methods declared in class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Modifier and Type	Method	Description
`protected Object`	`clone()`	Creates and returns a copy of this object.
`boolean`	`equals(Object obj)`	Indicates whether some other object is "equal to" this one.
`protected void`	`finalize()`	Deprecated, for removal: This API element is subject to removal in a future version. Finalization is deprecated and subject to removal in a future release.
`final Class<?>`	`getClass()`	Returns the runtime class of this `Object`.
`int`	`hashCode()`	Returns a hash code value for this object.
`final void`	`notify()`	Wakes up a single thread that is waiting on this object's monitor.
`final void`	`notifyAll()`	Wakes up all threads that are waiting on this object's monitor.
`String`	`toString()`	Returns a string representation of the object.
`final void`	`wait()`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted.
`final void`	`wait(long timeoutMillis)`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.
`final void`	`wait(long timeoutMillis, int nanos)`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

Constructor Details

SctpServerChannel

protected SctpServerChannel(SelectorProvider provider)

Initializes a new instance of this class.

Parameters:: provider - The selector provider for this channel

Method Details

open

public static SctpServerChannel open() throws IOException

Opens an SCTP server channel.

The new channel's socket is initially unbound; it must be bound to a specific address via one of its socket's bind methods before associations can be accepted.

Returns:: A new SCTP server channel
Throws:: UnsupportedOperationException - If the SCTP protocol is not supported; IOException - If an I/O error occurs

accept

public abstract SctpChannel accept() throws IOException

Accepts an association on this channel's socket.

If this channel is in non-blocking mode then this method will immediately return null if there are no pending associations. Otherwise it will block indefinitely until a new association is available or an I/O error occurs.

The SCTPChannel returned by this method, if any, will be in blocking mode regardless of the blocking mode of this channel.

Returns:: The SCTP channel for the new association, or null if this channel is in non-blocking mode and no association is available to be accepted
Throws:: ClosedChannelException - If this channel is closed; AsynchronousCloseException - If another thread closes this channel while the accept operation is in progress; ClosedByInterruptException - If another thread interrupts the current thread while the accept operation is in progress, thereby closing the channel and setting the current thread's interrupted status; NotYetBoundException - If this channel's socket has not yet been bound; IOException - If some other I/O error occurs

bind

public final SctpServerChannel bind(SocketAddress local) throws IOException

Binds the channel's socket to a local address and configures the socket to listen for associations.

This method works as if invoking it were equivalent to evaluating the expression:

bind(local, 0);

Parameters:: local - The local address to bind the socket, or null to bind the socket to an automatically assigned socket address
Returns:: This channel
Throws:: ClosedChannelException - If this channel is closed; AlreadyBoundException - If this channel is already bound; UnsupportedAddressTypeException - If the type of the given address is not supported; IOException - If some other I/O error occurs

bind

public abstract SctpServerChannel bind(SocketAddress local, int backlog) throws IOException

Binds the channel's socket to a local address and configures the socket to listen for associations.

This method is used to establish a relationship between the socket and the local address. 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.

The backlog parameter is the maximum number of pending associations on the socket. Its exact semantics are implementation specific. An implementation may impose an implementation specific maximum length or may choose to ignore the parameter. If the backlog parameter has the value 0, or a negative value, then an implementation specific default is used.

Parameters:: local - The local address to bind the socket, or null to bind the socket to an automatically assigned socket address; backlog - The maximum number of pending associations
Returns:: This channel
Throws:: ClosedChannelException - If this channel is closed; AlreadyBoundException - If this channel is already bound; UnsupportedAddressTypeException - If the type of the given address is not supported; IOException - If some other I/O error occurs

bindAddress

public abstract SctpServerChannel bindAddress(InetAddress address) 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.

New associations accepted after this method successfully completes will be associated with the given address.

Parameters:: address - The address to add to the bound addresses for the socket
Returns:: This channel
Throws:: ClosedChannelException - If this channel is closed; NotYetBoundException - If this channel is not yet bound; AlreadyBoundException - If this channel is already bound to the given address; IllegalArgumentException - If address is null or the wildcard address; IOException - If some other I/O error occurs

unbindAddress

public abstract SctpServerChannel unbindAddress(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.

New associations accepted after this method successfully completes will not be associated with the given address.

Parameters:: address - The address to remove from the bound addresses for the socket
Returns:: This channel
Throws:: ClosedChannelException - If this channel is closed; NotYetBoundException - If this channel is not yet bound; IllegalArgumentException - If address is null or the wildcard address; IllegalUnbindException - If the implementation does not support removing addresses from a listening socket, address is not bound to the channel's socket, or the channel has only one address bound to it; IOException - If some other I/O error occurs

getAllLocalAddresses

public abstract Set<SocketAddress> getAllLocalAddresses() throws IOException

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

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
Throws:: ClosedChannelException - If the channel is closed; IOException - If an I/O error occurs

getOption

public abstract <T> T getOption(SctpSocketOption<T> name) throws IOException

Returns the value of a socket option.

Type Parameters:

T - The type of the socket option value

Parameters:

name - The socket option

Returns:

The value of the socket option. A value of null may be a valid value for some socket options.

Throws:

UnsupportedOperationException - If the socket option is not supported by this channel

ClosedChannelException - If this channel is closed

IOException - If an I/O error occurs

See Also:

setOption

public abstract <T> SctpServerChannel setOption(SctpSocketOption<T> name, T value) throws IOException

Sets the value of a socket option.

Type Parameters:

T - The type of the socket option value

Parameters:

name - The socket option

value - The value of the socket option. A value of null may be a valid value for some socket options.

Returns:

This channel

Throws:

UnsupportedOperationException - If the socket option is not supported by this channel

IllegalArgumentException - If the value is not a valid value for this socket option

ClosedChannelException - If this channel is closed

IOException - If an I/O error occurs

See Also:

supportedOptions

public abstract Set<SctpSocketOption<?>> supportedOptions()

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

validOps

public final int validOps()

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

SCTP server channels only support the accepting of new associations, so this method returns SelectionKey.OP_ACCEPT.

Specified by:: validOps in class SelectableChannel
Returns:: The valid-operation set

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