Module jdk.sctp
Package com.sun.nio.sctp

# Class SctpServerChannel

java.lang.Object
java.nio.channels.spi.AbstractInterruptibleChannel
java.nio.channels.SelectableChannel
java.nio.channels.spi.AbstractSelectableChannel
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

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

Constructors
Modifier | Constructor | Description
--- | --- | ---
`protected` | `SctpServerChannel​(SelectorProvider provider)` | 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.
`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.
`int` | `validOps()` | Returns an operation set identifying this channel's supported operations.

### Methods declared in class java.nio.channels.spi.AbstractSelectableChannel

`configureBlocking, implCloseChannel, implCloseSelectableChannel, implConfigureBlocking, provider, register`

### Methods declared in class java.nio.channels.SelectableChannel

`blockingLock, isBlocking, isRegistered, keyFor, register`

### Methods declared in class java.nio.channels.spi.AbstractInterruptibleChannel

`begin, close, end`

### Methods declared in class java.lang.Object

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

### Methods declared in interface java.nio.channels.Channel

`isOpen`

## 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.

If a security manager has been installed then for each new association this method verifies that the address and port number of the assocaitions's remote peer are permitted by the security manager's `checkAccept` method.

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 interrupt status
  `NotYetBoundException` - If this channel's socket has not yet been bound
  `SecurityException` - If a security manager has been installed and it does not permit access to the remote peer of the new association
  `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
  `SecurityException` - If a security manager has been installed and its `checkListen` method denies the operation
  `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
  `SecurityException` - If a security manager has been installed and its `checkListen` method denies the operation
  `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:
  `SctpStandardSocketOptions`

### 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:
  `SctpStandardSocketOptions`

### 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