Java Scheduler类代码示例

import reactor.core.scheduler.Scheduler; //导入依赖的package包/类
@Override
public Flux<Employee> readEmployeesByDescAge() {
	Scheduler subWorker = Schedulers.newSingle("sub-thread");
	Scheduler pubWorker = Schedulers.newSingle("pub-thread");
	Supplier<Flux<Employee>> deferredTask = ()->{
		System.out.println("flux:defer task executor: "+ Thread.currentThread().getName());
		System.out.println("flux:defer task executor login: " + SecurityContextHolder.getContext().getAuthentication().getPrincipal());
		return Flux.fromIterable(employeeDaoImpl.getEmployees());
	};
	Comparator<Employee> descAge = (e1, e2) -> {
		System.out.println("flux:sort task executor: " + Thread.currentThread().getName());
		System.out.println("flux:sort task executor login: " + SecurityContextHolder.getContext().getAuthentication().getPrincipal());
		if(e1.getAge().compareTo(e2.getAge()) == 0){
			return 0;
		} else if(e1.getAge().compareTo(e2.getAge()) > 0){
			return -1;
		} else return 1;
	};
	Flux<Employee> deferred = Flux.defer(deferredTask).sort(descAge).subscribeOn(subWorker).publishOn(pubWorker);
	return deferred;
}
 

import reactor.core.scheduler.Scheduler; //导入依赖的package包/类
@Test
public void sampleZipTest3() throws Exception {
	int elements = 1;
	CountDownLatch latch = new CountDownLatch(elements + 1);
	EmitterProcessor<SensorData> sensorDataProcessor = EmitterProcessor.create();
	Scheduler scheduler = Schedulers.single();

	sensorDataProcessor.publishOn(scheduler)
	                   .subscribe(d -> latch.countDown(), null, latch::countDown);

	Flux.zip(Flux.just(new SensorData(2L, 12.0f)), Flux.just(new SensorData(1L, 14.0f)), this::computeMin)
	    .log("zip3")
	    .subscribe(sensorDataProcessor);

	awaitLatch(null, latch);
	scheduler.dispose();
}
 

import reactor.core.scheduler.Scheduler; //导入依赖的package包/类
@Override
public Flux<Employee> readEmployeesFlux(int age) {
	Scheduler subWorker = Schedulers.newSingle("sub-thread");
	Scheduler pubWorker = Schedulers.newSingle("pub-thread");
	Predicate<Employee> validAge = (e) -> {
		System.out.println("flux:filter task executor: " + Thread.currentThread().getName());
		System.out.println("flux:filter task executor login: " + SecurityContextHolder.getContext().getAuthentication().getPrincipal());
		return e.getAge() > age;
	};
	Supplier<Flux<Employee>> deferredTask = ()->{
		System.out.println("flux:defer task executor: " + Thread.currentThread().getName());
		System.out.println("flux:defer task executor login: " + SecurityContextHolder.getContext().getAuthentication().getPrincipal());
		return Flux.fromIterable(employeeDaoImpl.getEmployees());
	};
	Flux<Employee> deferred = Flux.defer(deferredTask).filter(validAge).subscribeOn(subWorker).publishOn(pubWorker);
	return deferred;
}
 

import reactor.core.scheduler.Scheduler; //导入依赖的package包/类
@Override
public Flux<Employee> readEmployeesByAscLastName() {
	Scheduler subWorker = Schedulers.newSingle("sub-thread");
	Scheduler pubWorker = Schedulers.newSingle("pub-thread");
	Supplier<Flux<Employee>> deferredTask = ()->{
		System.out.println("flux:defer task executor: " + Thread.currentThread().getName());
		System.out.println("flux:defer task executor login: " + SecurityContextHolder.getContext().getAuthentication().getPrincipal());
		return Flux.fromIterable(employeeDaoImpl.getEmployees());
	};
	Comparator<Employee> descLName = (e1, e2) -> {
		System.out.println("flux:sort task executor: " + Thread.currentThread().getName());
		System.out.println("flux:sort task executor login: " + SecurityContextHolder.getContext().getAuthentication().getPrincipal());
		return e1.getLastName().compareTo(e2.getLastName());
	};
	Flux<Employee> deferred = Flux.defer(deferredTask).sort(descLName).subscribeOn(subWorker).publishOn(pubWorker);
	return deferred;
}
 

import reactor.core.scheduler.Scheduler; //导入依赖的package包/类
@Test
public void assertNextWithSubscribeOnDirectProcessor() {
	Scheduler scheduler = Schedulers.newElastic("test");
	DirectProcessor<Integer> processor = DirectProcessor.create();
	Mono<Integer> doAction = Mono.fromSupplier(() -> 22)
	                             .doOnNext(processor::onNext)
	                             .subscribeOn(scheduler);

	assertThatExceptionOfType(AssertionError.class)
			.isThrownBy(
					StepVerifier.create(processor)
					            .then(doAction::subscribe)
					            .assertNext(v -> assertThat(v).isEqualTo(23))
					            .thenCancel()
							::verify);
}
 

import reactor.core.scheduler.Scheduler; //导入依赖的package包/类
FluxPublishOn(Flux<? extends T> source,
		Scheduler scheduler,
		boolean delayError,
		int prefetch,
		int lowTide,
		Supplier<? extends Queue<T>> queueSupplier) {
	super(source);
	if (prefetch <= 0) {
		throw new IllegalArgumentException("prefetch > 0 required but it was " + prefetch);
	}
	this.scheduler = Objects.requireNonNull(scheduler, "scheduler");
	this.delayError = delayError;
	this.prefetch = prefetch;
	this.lowTide = lowTide;
	this.queueSupplier = Objects.requireNonNull(queueSupplier, "queueSupplier");
}
 

import reactor.core.scheduler.Scheduler; //导入依赖的package包/类
/**
 * Run subscribe, onSubscribe and request on a specified {@link Scheduler}'s {@link Worker}.
 * As such, placing this operator anywhere in the chain will also impact the execution
 * context of onNext/onError/onComplete signals from the beginning of the chain up to
 * the next occurrence of a {@link #publishOn(Scheduler) publishOn}.
 * <p>
 * <img class="marble" src="https://raw.githubusercontent.com/reactor/reactor-core/v3.1.3.RELEASE/src/docs/marble/subscribeon1.png" alt="">
 *
 * <blockquote><pre>
 * {@code mono.subscribeOn(Schedulers.parallel()).subscribe()) }
 * </pre></blockquote>
 *
 * @param scheduler a {@link Scheduler} providing the {@link Worker} where to subscribe
 *
 * @return a {@link Flux} requesting asynchronously
 * @see #publishOn(Scheduler)
 */
public final Mono<T> subscribeOn(Scheduler scheduler) {
	if(this instanceof Callable) {
		if (this instanceof Fuseable.ScalarCallable) {
			try {
				T value = block();
				return onAssembly(new MonoSubscribeOnValue<>(value, scheduler));
			}
			catch (Throwable t) {
				//leave MonoSubscribeOnCallable defer error
			}
		}
		@SuppressWarnings("unchecked")
		Callable<T> c = (Callable<T>)this;
		return onAssembly(new MonoSubscribeOnCallable<>(c,
				scheduler));
	}
	return onAssembly(new MonoSubscribeOn<>(this, scheduler));
}
 

import reactor.core.scheduler.Scheduler; //导入依赖的package包/类
@Test(timeout = 5_000)
public void testBufferSize1Created() throws Exception {
	TopicProcessor<String> broadcast = TopicProcessor.<String>builder().name("share-name").bufferSize(1).autoCancel(true).build();

	int simultaneousSubscribers = 3000;
	CountDownLatch latch = new CountDownLatch(simultaneousSubscribers);
	Scheduler scheduler = Schedulers.single();

	FluxSink<String> sink = broadcast.sink();
	Flux<String> flux = broadcast.filter(Objects::nonNull)
	                             .publishOn(scheduler)
	                             .cache(1);

	for (int i = 0; i < simultaneousSubscribers; i++) {
		flux.subscribe(s -> latch.countDown());
	}
	sink.next("data");

	assertThat(latch.await(4, TimeUnit.SECONDS))
			.overridingErrorMessage("Data not received")
			.isTrue();
}
 

import reactor.core.scheduler.Scheduler; //导入依赖的package包/类
FluxBufferTimeout(Flux<T> source,
		int maxSize,
		long timespan,
		Scheduler timer,
		Supplier<C> bufferSupplier) {
	super(source);
	if (timespan <= 0) {
		throw new IllegalArgumentException("Timeout period must be strictly positive");
	}
	if (maxSize <= 0) {
		throw new IllegalArgumentException("maxSize must be strictly positive");
	}
	this.timer = Objects.requireNonNull(timer, "Timer");
	this.timespan = timespan;
	this.batchSize = maxSize;
	this.bufferSupplier = Objects.requireNonNull(bufferSupplier, "bufferSupplier");
}
 

import reactor.core.scheduler.Scheduler; //导入依赖的package包/类
final Flux<T> publishOn(Scheduler scheduler, boolean delayError, int prefetch, int lowTide) {
	if (this instanceof Callable) {
		if (this instanceof Fuseable.ScalarCallable) {
			@SuppressWarnings("unchecked")
			Fuseable.ScalarCallable<T> s = (Fuseable.ScalarCallable<T>) this;
			try {
				return onAssembly(new FluxSubscribeOnValue<>(s.call(), scheduler));
			}
			catch (Exception e) {
				//leave FluxSubscribeOnCallable defer exception call
			}
		}
		@SuppressWarnings("unchecked")
		Callable<T> c = (Callable<T>)this;
		return onAssembly(new FluxSubscribeOnCallable<>(c, scheduler));
	}

	return onAssembly(new FluxPublishOn<>(this, scheduler, delayError, prefetch, lowTide, Queues.get(prefetch)));
}
 

import reactor.core.scheduler.Scheduler; //导入依赖的package包/类
@Test
public void testSubmitSession() throws Exception {
	FluxProcessor<Integer, Integer> processor = EmitterProcessor.create();
	AtomicInteger count = new AtomicInteger();
	CountDownLatch latch = new CountDownLatch(1);
	Scheduler scheduler = Schedulers.parallel();
	processor.publishOn(scheduler)
	         .delaySubscription(Duration.ofMillis(1000))
	         .limitRate(1)
	         .subscribe(d -> {
		         count.incrementAndGet();
		         latch.countDown();
	         });

	FluxSink<Integer> session = processor.sink();
	session.next(1);
	//System.out.println(emission);
	session.complete();

	latch.await(5, TimeUnit.SECONDS);
	Assert.assertTrue("latch : " + count, count.get() == 1);
	scheduler.dispose();
}
 

import reactor.core.scheduler.Scheduler; //导入依赖的package包/类
/**
 * https://gist.github.com/nithril/444d8373ce67f0a8b853 Contribution by Nicolas Labrot
 * @throws InterruptedException on interrupt
 */
@Test
public void testParallelWithJava8StreamsInput() throws InterruptedException {
	Scheduler supplier = Schedulers.newParallel("test-p", 2);

	int max = ThreadLocalRandom.current()
	                           .nextInt(100, 300);
	CountDownLatch countDownLatch = new CountDownLatch(max);

	Flux<Integer> worker = Flux.range(0, max)
	                                 .publishOn(asyncGroup);
	worker.parallel(2)
	      .runOn(supplier)
	      .map(v -> v)
	      .subscribe(v -> countDownLatch.countDown());

	countDownLatch.await(10, TimeUnit.SECONDS);
	Assert.assertEquals(0, countDownLatch.getCount());
}
 

import reactor.core.scheduler.Scheduler; //导入依赖的package包/类
@Test
public void consistentMultithreadingWithPartition() throws InterruptedException {
	Scheduler supplier1 = Schedulers.newParallel("groupByPool", 2);
	Scheduler supplier2 = Schedulers.newParallel("partitionPool", 5);

	CountDownLatch latch = new CountDownLatch(10);

	/*Disposable c = */Flux.range(1, 10)
	                     .groupBy(n -> n % 2 == 0)
	                     .flatMap(stream -> stream.publishOn(supplier1)
	                                            .log("groupBy-" + stream.key()))
	                     .parallel(5)
	                     .runOn(supplier2)
	                     .sequential()
	                     .publishOn(asyncGroup)
	                     .log("join")
	                     .subscribe(t -> {
		                   latch.countDown();
	                   });


	latch.await(30, TimeUnit.SECONDS);
	assertThat("Not totally dispatched: " + latch.getCount(), latch.getCount() == 0);
	supplier1.dispose();
	supplier2.dispose();
}
 

import reactor.core.scheduler.Scheduler; //导入依赖的package包/类
@Test
public void crossRangePerfDefault() {
	AssertSubscriber<Integer> ts = AssertSubscriber.create();

	Scheduler scheduler = Schedulers.fromExecutorService(exec);

	int count = 1000;

	Flux<Integer> source = Flux.range(1, count)
	                           .flatMap(v -> Flux.range(v, 2), false, 128, 32);

	source.publishOn(scheduler)
	      .subscribe(ts);

	if (!ts.await(Duration.ofSeconds(10))
	       .isTerminated()) {
		ts.cancel();
	}

	ts.assertValueCount(count * 2)
	  .assertNoError()
	  .assertComplete();
}
 

import reactor.core.scheduler.Scheduler; //导入依赖的package包/类
@Test
public void onNextOnDisposedSchedulerThrows() {
	Scheduler scheduler = Schedulers.newSingle("onNextOnDisposedSchedulerThrows");
	scheduler.dispose();
	Mono<String> source = Mono.just("foo").hide();

	try {
		StepVerifier.create(new MonoDelayElement<>(source, 2, TimeUnit.SECONDS, scheduler))
		            .expectSubscription()
		            .verifyComplete(); //complete not relevant
		fail("expected exception here");
	}
	catch (Throwable e) {
		Throwable t = Exceptions.unwrap(e);

		assertThat(t).isEqualTo(e)
	                 .isInstanceOf(RejectedExecutionException.class)
	                 .hasMessage("Scheduler unavailable");

		assertThat(e).satisfies(Exceptions::isBubbling);
	}
}