java.nio.channels
Class ServerSocketChannel

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

All Implemented Interfaces:

Closeable, Channel, InterruptibleChannel

public abstract class ServerSocketChannel
extends AbstractSelectableChannel

A ServerSocketChannel is a partly abstracted stream-oriented listening socket which is selectable. Binding and manipulation of socket options can only be done through the associated ServerSocket object, returned by calling socket method. ServerSocketChannels can not be constructed for a pre-existing server socket, nor can it be assigned a SocketImpl.

A Server-Socket channel is open but not bound when created by open method. (Calling accept before bound will cause a NotYetBoundException). It can be bound by calling the bind method of a related ServerSocket instance.

Constructor Summary

protected

ServerSocketChannel(SelectorProvider selectorProvider) Construct a new instance for ServerSocketChannel

Method Summary

abstract SocketChannel	accept() Accepts a connection to this socket.
static ServerSocketChannel	open() Create an open and unbound server-socket channel.
abstract ServerSocket	socket() Return the related server-socket of this channel.
int	validOps() Get the valid operations of this channel.

Methods inherited from class java.nio.channels.spi.AbstractSelectableChannel

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

Methods inherited from class java.nio.channels.SelectableChannel

register

Methods inherited from class java.nio.channels.spi.AbstractInterruptibleChannel

begin, close, end, isOpen

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.nio.channels.Channel

close, isOpen

Constructor Detail

ServerSocketChannel

protected ServerSocketChannel(SelectorProvider selectorProvider)

Construct a new instance for ServerSocketChannel

Parameters:

selectorProvider - An instance of SelectorProvider

Method Detail

open

public static ServerSocketChannel open()
                                throws IOException

Create an open and unbound server-socket channel.

This channel is got by calling openServerSocketChannel method of the default SelectorProvider instance.

Returns:

The new created channel which is open but unbound.

Throws:

IOException - If some IO problem occurs.

validOps

public final int validOps()

Get the valid operations of this channel. Server-socket channels support accepting operation.Currently the only supported operation is OP_ACCEPT. It always returns SelectionKey.OP_ACCEPT.

Specified by:

validOps in class SelectableChannel

Returns:

Valid operations in bit-set.

See Also:

SelectableChannel.validOps()

socket

public abstract ServerSocket socket()

Return the related server-socket of this channel. All public methods declared in returned object should be declared in ServerSocket.

Returns:

The related ServerSocket instance.

accept

public abstract SocketChannel accept()
                              throws IOException

Accepts a connection to this socket.

It returns null when the channel is non-blocking and no connections available, otherwise it blocks indefinitely until a new connection is available or an I/O error occurs. The returned channel will be in blocking mode any way.

This method just execute the same security checks as the accept method of the ServerSocket class.

Returns:

The accepted SocketChannel instance, or null as the channel is non-blocking and no connections available.

Throws:

ClosedChannelException - If the channel is already closed.

AsynchronousCloseException - If the channel is closed by another thread while this method is in operation.

ClosedByInterruptException - If another thread interrupts the calling thread while the operation is in progress. The calling thread will have the interrupt state set, and the channel will be closed.

NotYetBoundException - If the socket has not yet been bound.

SecurityException - If there is a security manager, and the new connection is not permitted to access.

IOException - Some other IO error occurred.