/**
* Marks the beginning of an I/O operation that might block indefinitely.
*
* <p>This method should be invoked in tandem with the {@link #end end} method, using a
* <tt>try</tt> ... <tt>finally</tt> block as shown <a href="#be">above</a>, in order to
* implement asynchronous closing and interruption for this channel.
*/
protected final void begin() {
if (interruptor == null) {
interruptor =
new Interruptible() {
public void interrupt(Thread target) {
synchronized (closeLock) {
if (!open) return;
open = false;
interrupted = target;
try {
AbstractInterruptibleChannel.this.implCloseChannel();
} catch (IOException x) {
}
}
}
};
}
blockedOn(interruptor);
Thread me = Thread.currentThread();
if (me.isInterrupted()) interruptor.interrupt(me);
}