1 /*
2 * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23
24 /* @test
25 * @bug 8199433
26 * @run testng SelectWithConsumer
27 * @summary Unit test for Selector select(Consumer), select(Consumer,long) and
28 * selectNow(Consumer)
29 */
30
31 import java.io.Closeable;
32 import java.io.IOException;
33 import java.net.InetSocketAddress;
34 import java.nio.ByteBuffer;
35 import java.nio.channels.ClosedSelectorException;
36 import java.nio.channels.Pipe;
37 import java.nio.channels.SelectionKey;
38 import java.nio.channels.Selector;
39 import java.nio.channels.ServerSocketChannel;
40 import java.nio.channels.SocketChannel;
41 import java.nio.channels.WritableByteChannel;
42 import java.util.concurrent.Executors;
43 import java.util.concurrent.ScheduledExecutorService;
44 import java.util.concurrent.TimeUnit;
45 import java.util.concurrent.atomic.AtomicInteger;
46 import static java.util.concurrent.TimeUnit.*;
47
48 import org.testng.annotations.AfterTest;
49 import org.testng.annotations.Test;
50 import static org.testng.Assert.*;
51
52 @Test
53 public class SelectWithConsumer {
54
55 /**
56 * Invoke the select methods that take an action and check that the
57 * accumulated ready ops notified to the action matches the expected ops.
58 */
59 void testActionInvoked(SelectionKey key, int expectedOps) throws Exception {
60 var callerThread = Thread.currentThread();
61 var sel = key.selector();
62 var interestOps = key.interestOps();
63 var notifiedOps = new AtomicInteger();
64
65 // select(Consumer)
66 if (expectedOps == 0)
67 sel.wakeup(); // ensure select does not block
68 notifiedOps.set(0);
69 int n = sel.select(k -> {
70 assertTrue(Thread.currentThread() == callerThread);
71 assertTrue(k == key);
72 int readyOps = key.readyOps();
73 assertTrue((readyOps & interestOps) != 0);
74 assertTrue((readyOps & notifiedOps.get()) == 0);
75 notifiedOps.set(notifiedOps.get() | readyOps);
76 });
77 assertTrue((n == 1) ^ (expectedOps == 0));
78 assertTrue(notifiedOps.get() == expectedOps);
79
80 // select(Consumer, timeout)
81 notifiedOps.set(0);
82 n = sel.select(k -> {
83 assertTrue(Thread.currentThread() == callerThread);
84 assertTrue(k == key);
85 int readyOps = key.readyOps();
86 assertTrue((readyOps & interestOps) != 0);
87 assertTrue((readyOps & notifiedOps.get()) == 0);
88 notifiedOps.set(notifiedOps.get() | readyOps);
89 }, 1000);
90 assertTrue((n == 1) ^ (expectedOps == 0));
91 assertTrue(notifiedOps.get() == expectedOps);
92
93 // selectNow(Consumer)
94 notifiedOps.set(0);
95 n = sel.selectNow(k -> {
96 assertTrue(Thread.currentThread() == callerThread);
97 assertTrue(k == key);
98 int readyOps = key.readyOps();
99 assertTrue((readyOps & interestOps) != 0);
100 assertTrue((readyOps & notifiedOps.get()) == 0);
101 notifiedOps.set(notifiedOps.get() | readyOps);
102 });
103 assertTrue((n == 1) ^ (expectedOps == 0));
104 assertTrue(notifiedOps.get() == expectedOps);
105 }
106
107 /**
108 * Test that an action is performed when a channel is ready for reading.
109 */
110 public void testReadable() throws Exception {
111 Pipe p = Pipe.open();
112 try (Selector sel = Selector.open()) {
113 Pipe.SinkChannel sink = p.sink();
114 Pipe.SourceChannel source = p.source();
115 source.configureBlocking(false);
116 SelectionKey key = source.register(sel, SelectionKey.OP_READ);
117
118 // write to sink to ensure source is readable
119 scheduleWrite(sink, messageBuffer(), 100, MILLISECONDS);
120
121 // test that action is invoked
122 testActionInvoked(key, SelectionKey.OP_READ);
123 } finally {
124 closePipe(p);
125 }
126 }
127
128 /**
129 * Test that an action is performed when a channel is ready for writing.
130 */
131 public void testWritable() throws Exception {
132 Pipe p = Pipe.open();
133 try (Selector sel = Selector.open()) {
134 Pipe.SourceChannel source = p.source();
135 Pipe.SinkChannel sink = p.sink();
136 sink.configureBlocking(false);
137 SelectionKey key = sink.register(sel, SelectionKey.OP_WRITE);
138
139 // test that action is invoked
140 testActionInvoked(key, SelectionKey.OP_WRITE);
141 } finally {
142 closePipe(p);
143 }
144 }
145
146 /**
147 * Test that an action is performed when a channel is ready for both
148 * reading and writing.
149 */
150 public void testReadableAndWriteable() throws Exception {
151 ServerSocketChannel ssc = null;
152 SocketChannel sc = null;
153 SocketChannel peer = null;
154 try (Selector sel = Selector.open()) {
155 ssc = ServerSocketChannel.open().bind(new InetSocketAddress(0));
156 sc = SocketChannel.open(ssc.getLocalAddress());
157 sc.configureBlocking(false);
158 SelectionKey key = sc.register(sel, (SelectionKey.OP_READ |
159 SelectionKey.OP_WRITE));
160
161 // accept connection and write data so the source is readable
162 peer = ssc.accept();
163 peer.write(messageBuffer());
164
165 // test that action is invoked
166 testActionInvoked(key, (SelectionKey.OP_READ | SelectionKey.OP_WRITE));
167 } finally {
168 if (ssc != null) ssc.close();
169 if (sc != null) sc.close();
170 if (peer != null) peer.close();
171 }
172 }
173
174 /**
175 * Test that the action is called for two selected channels
176 */
177 public void testTwoChannels() throws Exception {
178 Pipe p = Pipe.open();
179 try (Selector sel = Selector.open()) {
180 Pipe.SourceChannel source = p.source();
181 Pipe.SinkChannel sink = p.sink();
182 source.configureBlocking(false);
183 sink.configureBlocking(false);
184 SelectionKey key1 = source.register(sel, SelectionKey.OP_READ);
185 SelectionKey key2 = sink.register(sel, SelectionKey.OP_WRITE);
186
187 // write to sink to ensure that the source is readable
188 sink.write(messageBuffer());
189
190 var counter = new AtomicInteger();
191
192 // select(Consumer)
193 counter.set(0);
194 int n = sel.select(k -> {
195 counter.incrementAndGet();
196 if (k == key1) {
197 assertTrue(k.isReadable());
198 } else if (k == key2) {
199 assertTrue(k.isWritable());
200 } else {
201 assertTrue(false);
202 }
203 });
204 assertTrue(n == 2);
205 assertTrue(counter.get() == 2);
206
207 // select(Consumer, timeout)
208 counter.set(0);
209 n = sel.select(k -> {
210 counter.incrementAndGet();
211 if (k == key1) {
212 assertTrue(k.isReadable());
213 } else if (k == key2) {
214 assertTrue(k.isWritable());
215 } else {
216 assertTrue(false);
217 }
218 }, 1000);
219 assertTrue(n == 2);
220 assertTrue(counter.get() == 2);
221
222 // selectNow(Consumer)
223 counter.set(0);
224 n = sel.selectNow(k -> {
225 counter.incrementAndGet();
226 if (k == key1) {
227 assertTrue(k.isReadable());
228 } else if (k == key2) {
229 assertTrue(k.isWritable());
230 } else {
231 assertTrue(false);
232 }
233 });
234 assertTrue(n == 2);
235 assertTrue(counter.get() == 2);
236 } finally {
237 closePipe(p);
238 }
239 }
240
241 /**
242 * Test calling select twice, the action should be invoked each time
243 */
244 public void testRepeatedSelect1() throws Exception {
245 Pipe p = Pipe.open();
246 try (Selector sel = Selector.open()) {
247 Pipe.SourceChannel source = p.source();
248 Pipe.SinkChannel sink = p.sink();
249 source.configureBlocking(false);
250 SelectionKey key = source.register(sel, SelectionKey.OP_READ);
251
252 // write to sink to ensure that the source is readable
253 sink.write(messageBuffer());
254
255 // test that action is invoked
256 testActionInvoked(key, SelectionKey.OP_READ);
257 testActionInvoked(key, SelectionKey.OP_READ);
258
259 } finally {
260 closePipe(p);
261 }
262 }
263
264 /**
265 * Test calling select twice. An I/O operation is performed after the
266 * first select so the channel will not be selected by the second select.
267 */
268 public void testRepeatedSelect2() throws Exception {
269 Pipe p = Pipe.open();
270 try (Selector sel = Selector.open()) {
271 Pipe.SourceChannel source = p.source();
272 Pipe.SinkChannel sink = p.sink();
273 source.configureBlocking(false);
274 SelectionKey key = source.register(sel, SelectionKey.OP_READ);
275
276 // write to sink to ensure that the source is readable
277 sink.write(messageBuffer());
278
279 // test that action is invoked
280 testActionInvoked(key, SelectionKey.OP_READ);
281
282 // read all bytes
283 int n;
284 ByteBuffer bb = ByteBuffer.allocate(100);
285 do {
286 n = source.read(bb);
287 bb.clear();
288 } while (n > 0);
289
290 // test that action is not invoked
291 testActionInvoked(key, 0);
292 } finally {
293 closePipe(p);
294 }
295 }
296
297 /**
298 * Test timeout
299 */
300 public void testTimeout() throws Exception {
301 Pipe p = Pipe.open();
302 try (Selector sel = Selector.open()) {
303 Pipe.SourceChannel source = p.source();
304 Pipe.SinkChannel sink = p.sink();
305 source.configureBlocking(false);
306 source.register(sel, SelectionKey.OP_READ);
307 long start = System.currentTimeMillis();
308 int n = sel.select(k -> assertTrue(false), 1000L);
309 long duration = System.currentTimeMillis() - start;
310 assertTrue(n == 0);
311 assertTrue(duration > 500, "select took " + duration + " ms");
312 } finally {
313 closePipe(p);
314 }
315 }
316
317 /**
318 * Test wakeup prior to select
319 */
320 public void testWakeupBeforeSelect() throws Exception {
321 // select(Consumer)
322 try (Selector sel = Selector.open()) {
323 sel.wakeup();
324 int n = sel.select(k -> assertTrue(false));
325 assertTrue(n == 0);
326 }
327
328 // select(Consumer, timeout)
329 try (Selector sel = Selector.open()) {
330 sel.wakeup();
331 long start = System.currentTimeMillis();
332 int n = sel.select(k -> assertTrue(false), 60*1000);
333 long duration = System.currentTimeMillis() - start;
334 assertTrue(n == 0);
335 assertTrue(duration < 5000, "select took " + duration + " ms");
336 }
337 }
338
339 /**
340 * Test wakeup during select
341 */
342 public void testWakeupDuringSelect() throws Exception {
343 // select(Consumer)
344 try (Selector sel = Selector.open()) {
345 scheduleWakeup(sel, 1, SECONDS);
346 int n = sel.select(k -> assertTrue(false));
347 assertTrue(n == 0);
348 }
349
350 // select(Consumer, timeout)
351 try (Selector sel = Selector.open()) {
352 scheduleWakeup(sel, 1, SECONDS);
353 long start = System.currentTimeMillis();
354 int n = sel.select(k -> assertTrue(false), 60*1000);
355 long duration = System.currentTimeMillis() - start;
356 assertTrue(n == 0);
357 assertTrue(duration > 500 && duration < 10*1000,
358 "select took " + duration + " ms");
359 }
360 }
361
362 /**
363 * Test invoking select with interrupt status set
364 */
365 public void testInterruptBeforeSelect() throws Exception {
366 // select(Consumer)
367 try (Selector sel = Selector.open()) {
368 Thread.currentThread().interrupt();
369 int n = sel.select(k -> assertTrue(false));
370 assertTrue(n == 0);
371 assertTrue(Thread.currentThread().isInterrupted());
372 assertTrue(sel.isOpen());
373 } finally {
374 Thread.currentThread().interrupted(); // clear interrupt status
375 }
376
377 // select(Consumer, timeout)
378 try (Selector sel = Selector.open()) {
379 Thread.currentThread().interrupt();
380 long start = System.currentTimeMillis();
381 int n = sel.select(k -> assertTrue(false), 60*1000);
382 long duration = System.currentTimeMillis() - start;
383 assertTrue(n == 0);
384 assertTrue(duration < 5000, "select took " + duration + " ms");
385 assertTrue(Thread.currentThread().isInterrupted());
386 assertTrue(sel.isOpen());
387 } finally {
388 Thread.currentThread().interrupted(); // clear interrupt status
389 }
390 }
391
392 /**
393 * Test interrupt thread during select
394 */
395 public void testInterruptDuringSelect() throws Exception {
396 // select(Consumer)
397 try (Selector sel = Selector.open()) {
398 scheduleInterrupt(Thread.currentThread(), 1, SECONDS);
399 int n = sel.select(k -> assertTrue(false));
400 assertTrue(n == 0);
401 assertTrue(Thread.currentThread().isInterrupted());
402 assertTrue(sel.isOpen());
403 } finally {
404 Thread.currentThread().interrupted(); // clear interrupt status
405 }
406
407 // select(Consumer, timeout)
408 try (Selector sel = Selector.open()) {
409 scheduleInterrupt(Thread.currentThread(), 1, SECONDS);
410 long start = System.currentTimeMillis();
411 int n = sel.select(k -> assertTrue(false), 60*1000);
412 long duration = System.currentTimeMillis() - start;
413 assertTrue(n == 0);
414 assertTrue(duration > 500 && duration < 5000,
415 "select took " + duration + " ms");
416 assertTrue(Thread.currentThread().isInterrupted());
417 assertTrue(sel.isOpen());
418 } finally {
419 Thread.currentThread().interrupted(); // clear interrupt status
420 }
421 }
422
423 /**
424 * Test invoking select on a closed selector
425 */
426 @Test(expectedExceptions = ClosedSelectorException.class)
427 public void testClosedSelector1() throws Exception {
428 Selector sel = Selector.open();
429 sel.close();
430 sel.select(k -> assertTrue(false));
431 }
432 @Test(expectedExceptions = ClosedSelectorException.class)
433 public void testClosedSelector2() throws Exception {
434 Selector sel = Selector.open();
435 sel.close();
436 sel.select(k -> assertTrue(false), 1000);
437 }
438 @Test(expectedExceptions = ClosedSelectorException.class)
439 public void testClosedSelector3() throws Exception {
440 Selector sel = Selector.open();
441 sel.close();
442 sel.selectNow(k -> assertTrue(false));
443 }
444
445 /**
446 * Test closing selector while in a selection operation
447 */
448 public void testCloseDuringSelect() throws Exception {
449 // select(Consumer)
450 try (Selector sel = Selector.open()) {
451 scheduleClose(sel, 3, SECONDS);
452 int n = sel.select(k -> assertTrue(false));
453 assertTrue(n == 0);
454 assertFalse(sel.isOpen());
455 }
456
457 // select(Consumer, timeout)
458 try (Selector sel = Selector.open()) {
459 scheduleClose(sel, 3, SECONDS);
460 long start = System.currentTimeMillis();
461 int n = sel.select(k -> assertTrue(false), 60*1000);
462 long duration = System.currentTimeMillis() - start;
463 assertTrue(n == 0);
464 assertTrue(duration > 2000 && duration < 10*1000,
465 "select took " + duration + " ms");
466 assertFalse(sel.isOpen());
467 }
468 }
469
470 /**
471 * Test action closing selector
472 */
473 @Test(expectedExceptions = ClosedSelectorException.class)
474 public void testActionClosingSelector() throws Exception {
475 Pipe p = Pipe.open();
476 try (Selector sel = Selector.open()) {
477 Pipe.SourceChannel source = p.source();
478 Pipe.SinkChannel sink = p.sink();
479 source.configureBlocking(false);
480 SelectionKey key = source.register(sel, SelectionKey.OP_READ);
481
482 // write to sink to ensure that the source is readable
483 sink.write(messageBuffer());
484
485 // should relay ClosedSelectorException
486 sel.select(k -> {
487 assertTrue(k == key);
488 try {
489 sel.close();
490 } catch (IOException ioe) { }
491 });
492 } finally {
493 closePipe(p);
494 }
495 }
496
497 /**
498 * Test that the action is invoked while synchronized on the selector and
499 * its selected-key set.
500 */
501 public void testLocks() throws Exception {
502 Pipe p = Pipe.open();
503 try (Selector sel = Selector.open()) {
504 Pipe.SourceChannel source = p.source();
505 Pipe.SinkChannel sink = p.sink();
506 source.configureBlocking(false);
507 SelectionKey key = source.register(sel, SelectionKey.OP_READ);
508
509 // write to sink to ensure that the source is readable
510 sink.write(messageBuffer());
511
512 // select(Consumer)
513 sel.select(k -> {
514 assertTrue(k == key);
515 assertTrue(Thread.holdsLock(sel));
516 assertFalse(Thread.holdsLock(sel.keys()));
517 assertTrue(Thread.holdsLock(sel.selectedKeys()));
518 });
519
520 // select(Consumer, timeout)
521 sel.select(k -> {
522 assertTrue(k == key);
523 assertTrue(Thread.holdsLock(sel));
524 assertFalse(Thread.holdsLock(sel.keys()));
525 assertTrue(Thread.holdsLock(sel.selectedKeys()));
526 }, 1000L);
527
528 // selectNow(Consumer)
529 sel.selectNow(k -> {
530 assertTrue(k == key);
531 assertTrue(Thread.holdsLock(sel));
532 assertFalse(Thread.holdsLock(sel.keys()));
533 assertTrue(Thread.holdsLock(sel.selectedKeys()));
534 });
535 } finally {
536 closePipe(p);
537 }
538 }
539
540 /**
541 * Test that selection operations remove cancelled keys from the selector's
542 * key and selected-key sets.
543 */
544 public void testCancel() throws Exception {
545 Pipe p = Pipe.open();
546 try (Selector sel = Selector.open()) {
547 Pipe.SinkChannel sink = p.sink();
548 Pipe.SourceChannel source = p.source();
549
550 // write to sink to ensure that the source is readable
551 sink.write(messageBuffer());
552
553 sink.configureBlocking(false);
554 source.configureBlocking(false);
555 SelectionKey key1 = sink.register(sel, SelectionKey.OP_WRITE);
556 SelectionKey key2 = source.register(sel, SelectionKey.OP_READ);
557
558 sel.selectNow();
559 assertTrue(sel.keys().contains(key1));
560 assertTrue(sel.keys().contains(key2));
561 assertTrue(sel.selectedKeys().contains(key1));
562 assertTrue(sel.selectedKeys().contains(key2));
563
564 // cancel key1
565 key1.cancel();
566 int n = sel.selectNow(k -> assertTrue(k == key2));
567 assertTrue(n == 1);
568 assertFalse(sel.keys().contains(key1));
569 assertTrue(sel.keys().contains(key2));
570 assertFalse(sel.selectedKeys().contains(key1));
571 assertTrue(sel.selectedKeys().contains(key2));
572
573 // cancel key2
574 key2.cancel();
575 n = sel.selectNow(k -> assertTrue(false));
576 assertTrue(n == 0);
577 assertFalse(sel.keys().contains(key1));
578 assertFalse(sel.keys().contains(key2));
579 assertFalse(sel.selectedKeys().contains(key1));
580 assertFalse(sel.selectedKeys().contains(key2));
581 } finally {
582 closePipe(p);
583 }
584 }
585
586 /**
587 * Test an action invoking select()
588 */
589 public void testReentrantSelect1() throws Exception {
590 Pipe p = Pipe.open();
591 try (Selector sel = Selector.open()) {
592 Pipe.SinkChannel sink = p.sink();
593 Pipe.SourceChannel source = p.source();
594 source.configureBlocking(false);
595 source.register(sel, SelectionKey.OP_READ);
596
597 // write to sink to ensure that the source is readable
598 scheduleWrite(sink, messageBuffer(), 100, MILLISECONDS);
599
600 int n = sel.select(k -> {
601 try {
602 sel.select();
603 assertTrue(false);
604 } catch (IOException ioe) {
605 throw new RuntimeException(ioe);
606 } catch (IllegalStateException expected) {
607 }
608 });
609 assertTrue(n == 1);
610 } finally {
611 closePipe(p);
612 }
613 }
614
615 /**
616 * Test an action invoking selectNow()
617 */
618 public void testReentrantSelect2() throws Exception {
619 Pipe p = Pipe.open();
620 try (Selector sel = Selector.open()) {
621 Pipe.SinkChannel sink = p.sink();
622 Pipe.SourceChannel source = p.source();
623
624 // write to sink to ensure that the source is readable
625 scheduleWrite(sink, messageBuffer(), 100, MILLISECONDS);
626
627 source.configureBlocking(false);
628 source.register(sel, SelectionKey.OP_READ);
629 int n = sel.select(k -> {
630 try {
631 sel.selectNow();
632 assertTrue(false);
633 } catch (IOException ioe) {
634 throw new RuntimeException(ioe);
635 } catch (IllegalStateException expected) {
636 }
637 });
638 assertTrue(n == 1);
639 } finally {
640 closePipe(p);
641 }
642 }
643
644 /**
645 * Test an action invoking select(Consumer)
646 */
647 public void testReentrantSelect3() throws Exception {
648 Pipe p = Pipe.open();
649 try (Selector sel = Selector.open()) {
650 Pipe.SinkChannel sink = p.sink();
651 Pipe.SourceChannel source = p.source();
652
653 // write to sink to ensure that the source is readable
654 scheduleWrite(sink, messageBuffer(), 100, MILLISECONDS);
655
656 source.configureBlocking(false);
657 source.register(sel, SelectionKey.OP_READ);
658 int n = sel.select(k -> {
659 try {
660 sel.select(x -> assertTrue(false));
661 assertTrue(false);
662 } catch (IOException ioe) {
663 throw new RuntimeException(ioe);
664 } catch (IllegalStateException expected) {
665 }
666 });
667 assertTrue(n == 1);
668 } finally {
669 closePipe(p);
670 }
671 }
672
673 /**
674 * Negative timeout
675 */
676 @Test(expectedExceptions = IllegalArgumentException.class)
677 public void testNegativeTimeout() throws Exception {
678 try (Selector sel = Selector.open()) {
679 sel.select(k -> { }, -1L);
680 }
681 }
682
683 /**
684 * Null action
685 */
686 @Test(expectedExceptions = NullPointerException.class)
687 public void testNull1() throws Exception {
688 try (Selector sel = Selector.open()) {
689 sel.select(null);
690 }
691 }
692 @Test(expectedExceptions = NullPointerException.class)
693 public void testNull2() throws Exception {
694 try (Selector sel = Selector.open()) {
695 sel.select(null, 1000);
696 }
697 }
698 @Test(expectedExceptions = NullPointerException.class)
699 public void testNull3() throws Exception {
700 try (Selector sel = Selector.open()) {
701 sel.selectNow(null);
702 }
703 }
704
705
706 // -- support methods ---
707
708 private final ScheduledExecutorService POOL = Executors.newScheduledThreadPool(1);
709
710 @AfterTest
711 void shutdownThreadPool() {
712 POOL.shutdown();
713 }
714
715 void scheduleWakeup(Selector sel, long delay, TimeUnit unit) {
716 POOL.schedule(() -> sel.wakeup(), delay, unit);
717 }
718
719 void scheduleInterrupt(Thread t, long delay, TimeUnit unit) {
720 POOL.schedule(() -> t.interrupt(), delay, unit);
721 }
722
723 void scheduleClose(Closeable c, long delay, TimeUnit unit) {
724 POOL.schedule(() -> {
725 try {
726 c.close();
727 } catch (IOException ioe) {
728 ioe.printStackTrace();
729 }
730 }, delay, unit);
731 }
732
733 void scheduleWrite(WritableByteChannel sink, ByteBuffer buf, long delay, TimeUnit unit) {
734 POOL.schedule(() -> {
735 try {
736 sink.write(buf);
737 } catch (IOException ioe) {
738 ioe.printStackTrace();
739 }
740 }, delay, unit);
741 }
742
743 static void closePipe(Pipe p) {
744 try { p.sink().close(); } catch (IOException ignore) { }
745 try { p.source().close(); } catch (IOException ignore) { }
746 }
747
748 static ByteBuffer messageBuffer() {
749 try {
750 return ByteBuffer.wrap("message".getBytes("UTF-8"));
751 } catch (Exception e) {
752 throw new RuntimeException(e);
753 }
754 }
755 }