java.nio.channels.AsynchronousFileChannel#close()源码实例Demo

@Test
public void writeAsynchronousFileChannelErrorInFlux() throws Exception {
	DataBuffer foo = stringBuffer("foo");
	DataBuffer bar = stringBuffer("bar");
	Flux<DataBuffer> flux =
			Flux.just(foo, bar).concatWith(Mono.error(new RuntimeException()));

	AsynchronousFileChannel channel =
			AsynchronousFileChannel.open(tempFile, StandardOpenOption.WRITE);

	Flux<DataBuffer> writeResult = DataBufferUtils.write(flux, channel);
	StepVerifier.create(writeResult)
			.consumeNextWith(stringConsumer("foo"))
			.consumeNextWith(stringConsumer("bar"))
			.expectError(RuntimeException.class)
			.verify();

	String result = String.join("", Files.readAllLines(tempFile));

	assertEquals("foobar", result);
	channel.close();
}
 

@Test
public void writeAsynchronousFileChannelCanceled() throws Exception {
	DataBuffer foo = stringBuffer("foo");
	DataBuffer bar = stringBuffer("bar");
	Flux<DataBuffer> flux = Flux.just(foo, bar);

	AsynchronousFileChannel channel =
			AsynchronousFileChannel.open(tempFile, StandardOpenOption.WRITE);

	Flux<DataBuffer> writeResult = DataBufferUtils.write(flux, channel);
	StepVerifier.create(writeResult, 1)
			.consumeNextWith(stringConsumer("foo"))
			.thenCancel()
			.verify();

	String result = String.join("", Files.readAllLines(tempFile));

	assertEquals("foo", result);
	channel.close();

	flux.subscribe(DataBufferUtils::release);
}
 

@Test
public void writeAsynchronousFileChannelErrorInFlux() throws Exception {
	DataBuffer foo = stringBuffer("foo");
	DataBuffer bar = stringBuffer("bar");
	Flux<DataBuffer> flux =
			Flux.just(foo, bar).concatWith(Mono.error(new RuntimeException()));

	AsynchronousFileChannel channel =
			AsynchronousFileChannel.open(tempFile, StandardOpenOption.WRITE);

	Flux<DataBuffer> writeResult = DataBufferUtils.write(flux, channel);
	StepVerifier.create(writeResult)
			.consumeNextWith(stringConsumer("foo"))
			.consumeNextWith(stringConsumer("bar"))
			.expectError(RuntimeException.class)
			.verify();

	String result = String.join("", Files.readAllLines(tempFile));

	assertEquals("foobar", result);
	channel.close();
}
 

@Test
public void writeAsynchronousFileChannelCanceled() throws Exception {
	DataBuffer foo = stringBuffer("foo");
	DataBuffer bar = stringBuffer("bar");
	Flux<DataBuffer> flux = Flux.just(foo, bar);

	AsynchronousFileChannel channel =
			AsynchronousFileChannel.open(tempFile, StandardOpenOption.WRITE);

	Flux<DataBuffer> writeResult = DataBufferUtils.write(flux, channel);
	StepVerifier.create(writeResult, 1)
			.consumeNextWith(stringConsumer("foo"))
			.thenCancel()
			.verify();

	String result = String.join("", Files.readAllLines(tempFile));

	assertEquals("foo", result);
	channel.close();

	flux.subscribe(DataBufferUtils::release);
}
 

/** Test leaks via AsynchronousFileChannel.open */
public void testLeakAsyncFileChannel() throws IOException, InterruptedException {
  Path dir = wrap(createTempDir());
  
  OutputStream file = Files.newOutputStream(dir.resolve("stillopen"));
  file.write(5);
  file.close();

  ExecutorService executorService = Executors.newFixedThreadPool(1,
      new NamedThreadFactory("async-io"));
  try {
    AsynchronousFileChannel leak = AsynchronousFileChannel.open(dir.resolve("stillopen"),
        Collections.emptySet(), executorService);
    Exception e = expectThrows(Exception.class, () -> dir.getFileSystem().close());
    assertTrue(e.getMessage().contains("file handle leaks"));
    leak.close();
  } finally {
    executorService.shutdown();
    executorService.awaitTermination(5, TimeUnit.SECONDS);
  }
}
 

/** Test AsynchronousFileChannel.open */
public void testAsyncFileChannel() throws IOException, InterruptedException {
  InfoStreamListener stream = new InfoStreamListener("newAsynchronousFileChannel");
  Path dir = wrap(createTempDir(), stream);

  ExecutorService executorService = Executors.newFixedThreadPool(1,
      new NamedThreadFactory("async-io"));
  try {
    Set<StandardOpenOption> opts = Set
        .of(StandardOpenOption.CREATE_NEW, StandardOpenOption.READ,
            StandardOpenOption.WRITE);
    AsynchronousFileChannel channel = AsynchronousFileChannel
        .open(dir.resolve("foobar"), opts, executorService);
    assertTrue(stream.sawMessage());
    channel.close();

    expectThrows(IOException.class, () -> AsynchronousFileChannel.open(dir.resolve("foobar"),
        opts, executorService));

    expectThrows(NoSuchFileException.class,
        () -> AsynchronousFileChannel.open(dir.resolve("doesNotExist.rip")));
  } finally {
    executorService.shutdown();
    executorService.awaitTermination(5, TimeUnit.SECONDS);
  }
}
 

@Test
public void writeAsynchronousFileChannel() throws Exception {
	DataBuffer foo = stringBuffer("foo");
	DataBuffer bar = stringBuffer("bar");
	DataBuffer baz = stringBuffer("baz");
	DataBuffer qux = stringBuffer("qux");
	Flux<DataBuffer> flux = Flux.just(foo, bar, baz, qux);

	AsynchronousFileChannel channel =
			AsynchronousFileChannel.open(tempFile, StandardOpenOption.WRITE);

	Flux<DataBuffer> writeResult = DataBufferUtils.write(flux, channel);
	verifyWrittenData(writeResult);
	channel.close();
}
 

@Test
public void writeAsynchronousFileChannel() throws Exception {
	DataBuffer foo = stringBuffer("foo");
	DataBuffer bar = stringBuffer("bar");
	DataBuffer baz = stringBuffer("baz");
	DataBuffer qux = stringBuffer("qux");
	Flux<DataBuffer> flux = Flux.just(foo, bar, baz, qux);

	AsynchronousFileChannel channel =
			AsynchronousFileChannel.open(tempFile, StandardOpenOption.WRITE);

	Flux<DataBuffer> writeResult = DataBufferUtils.write(flux, channel);
	verifyWrittenData(writeResult);
	channel.close();
}