Class AbstractSelectableChannel

Constructor Detail

• AbstractSelectableChannel

  protected AbstractSelectableChannel(SelectorProvider provider)

  Initializes a new instance of this class.

Method Detail

• provider

  public final SelectorProvider provider()

  Returns the provider that created this channel.

  Specified by:

  provider in class SelectableChannel

  Returns:

  The provider that created this channel

• isRegistered

  public final boolean isRegistered()

  Description copied from class: SelectableChannel
  Tells whether or not this channel is currently registered with any selectors. A newly-created channel is not registered.

  Due to the inherent delay between key cancellation and channel deregistration, a channel may remain registered for some time after all of its keys have been cancelled. A channel may also remain registered for some time after it is closed.

  Specified by:

  isRegistered in class SelectableChannel

  Returns:

  true if, and only if, this channel is registered

• keyFor

  public final SelectionKey keyFor(Selector sel)

  Description copied from class: SelectableChannel
  Retrieves the key representing the channel's registration with the given selector.

  Specified by:

  keyFor in class SelectableChannel

  Returns:

  The key returned when this channel was last registered with the given selector, or null if this channel is not currently registered with that selector

• register

  public final SelectionKey register(Selector sel,
                      int ops,
                      Object att)
                              throws ClosedChannelException

  Registers this channel with the given selector, returning a selection key.

  This method first verifies that this channel is open and that the given initial interest set is valid.

  If this channel is already registered with the given selector then the selection key representing that registration is returned after setting its interest set to the given value.

  Otherwise this channel has not yet been registered with the given selector, so the register method of the selector is invoked while holding the appropriate locks. The resulting key is added to this channel's key set before being returned.

  Specified by:

  register in class SelectableChannel

  Parameters:

  sel - The selector with which this channel is to be registered

  ops - The interest set for the resulting key

  att - The attachment for the resulting key; may be null

  Returns:

  A key representing the registration of this channel with the given selector

  Throws:

  ClosedSelectorException - If the selector is closed

  IllegalBlockingModeException - If this channel is in blocking mode

  IllegalSelectorException - If this channel was not created by the same provider as the given selector

  CancelledKeyException - If this channel is currently registered with the given selector but the corresponding key has already been cancelled

  IllegalArgumentException - If a bit in the ops set does not correspond to an operation that is supported by this channel, that is, if set & ~validOps() != 0

  ClosedChannelException - If this channel is closed

• implCloseChannel

  protected final void implCloseChannel()
                                 throws IOException

  Closes this channel.

  This method, which is specified in the AbstractInterruptibleChannel class and is invoked by the close method, in turn invokes the implCloseSelectableChannel method in order to perform the actual work of closing this channel. It then cancels all of this channel's keys.

  Specified by:

  implCloseChannel in class AbstractInterruptibleChannel

  Throws:

  IOException - If an I/O error occurs while closing the channel

• implCloseSelectableChannel

  protected abstract void implCloseSelectableChannel()
                                              throws IOException

  Closes this selectable channel.

  This method is invoked by the close method in order to perform the actual work of closing the channel. This method is only invoked if the channel has not yet been closed, and it is never invoked more than once.

  An implementation of this method must arrange for any other thread that is blocked in an I/O operation upon this channel to return immediately, either by throwing an exception or by returning normally.

  Throws:

  IOException

• isBlocking

  public final boolean isBlocking()

  Description copied from class: SelectableChannel
  Tells whether or not every I/O operation on this channel will block until it completes. A newly-created channel is always in blocking mode.

  If this channel is closed then the value returned by this method is not specified.

  Specified by:

  isBlocking in class SelectableChannel

  Returns:

  true if, and only if, this channel is in blocking mode

• blockingLock

  public final Object blockingLock()

  Description copied from class: SelectableChannel
  Retrieves the object upon which the configureBlocking and register methods synchronize. This is often useful in the implementation of adaptors that require a specific blocking mode to be maintained for a short period of time.

  Specified by:

  blockingLock in class SelectableChannel

  Returns:

  The blocking-mode lock object

• configureBlocking

  public final SelectableChannel configureBlocking(boolean block)
                                            throws IOException

  Adjusts this channel's blocking mode.

  If the given blocking mode is different from the current blocking mode then this method invokes the implConfigureBlocking method, while holding the appropriate locks, in order to change the mode.

  Specified by:

  configureBlocking in class SelectableChannel

  Parameters:

  block - If true then this channel will be placed in blocking mode; if false then it will be placed non-blocking mode

  Returns:

  This selectable channel

  Throws:

  ClosedChannelException - If this channel is closed

  IOException - If an I/O error occurs

• implConfigureBlocking

  protected abstract void implConfigureBlocking(boolean block)
                                         throws IOException

  Adjusts this channel's blocking mode.

  This method is invoked by the configureBlocking method in order to perform the actual work of changing the blocking mode. This method is only invoked if the new mode is different from the current mode.

  Throws:

  IOException - If an I/O error occurs