本文整理了Java中io.reactivex.Flowable.elementAtOrError()方法的一些代码示例，展示了Flowable.elementAtOrError()的具体用法。这些代码示例主要来源于Github/Stackoverflow/Maven等平台，是从一些精选项目中提取出来的代码，具有较强的参考意义，能在一定程度帮忙到你。Flowable.elementAtOrError()方法的具体详情如下：
包路径：io.reactivex.Flowable
类名称：Flowable
方法名：elementAtOrError

Flowable.elementAtOrError介绍

[英]Returns a Flowable that emits the item found at a specified index in a sequence of emissions from this Flowable or signals a NoSuchElementException if this Flowable has fewer elements than index.

Backpressure: The operator honors backpressure from downstream and consumes the source Publisher in an unbounded manner (i.e., no backpressure applied to it). Scheduler: elementAtOrError does not operate by default on a particular Scheduler.
[中]返回一个FlowTable，该FlowTable在该FlowTable的一系列发射中发射在指定索引处找到的项，或者如果该FlowTable的元素少于索引，则发出NosTouchElementException信号。
背压：操作员接受来自下游的背压，并以无限制的方式使用源发布服务器（即，不向其施加背压）。Scheduler:ElementAtoreRor默认情况下不会在特定的计划程序上运行。

代码示例

代码示例来源：origin: ReactiveX/RxJava

/**
 * Returns a Single that emits only the very first item emitted by this Flowable or
 * signals a {@link NoSuchElementException} if this Flowable is empty.
 * <p>
 * <img width="640" height="237" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/firstOrError.png" alt="">
 * <dl>
 *  <dt><b>Backpressure:</b></dt>
 *  <dd>The operator honors backpressure from downstream and consumes the source {@code Publisher} in an
 *  unbounded manner (i.e., without applying backpressure).</dd>
 *  <dt><b>Scheduler:</b></dt>
 *  <dd>{@code firstOrError} does not operate by default on a particular {@link Scheduler}.</dd>
 * </dl>
 *
 * @return the new Single instance
 * @see <a href="http://reactivex.io/documentation/operators/first.html">ReactiveX operators documentation: First</a>
 */
@CheckReturnValue
@BackpressureSupport(BackpressureKind.SPECIAL) // take may trigger UNBOUNDED_IN
@SchedulerSupport(SchedulerSupport.NONE)
public final Single<T> firstOrError() {
  return elementAtOrError(0);
}

代码示例来源：origin: ReactiveX/RxJava

@Test(expected = IndexOutOfBoundsException.class)
public void elementAtOrErrorNegativeIndex() {
  Flowable.empty()
    .elementAtOrError(-1);
}

代码示例来源：origin: redisson/redisson

/**
 * Returns a Single that emits only the very first item emitted by this Flowable or
 * signals a {@link NoSuchElementException} if this Flowable is empty.
 * <p>
 * <img width="640" height="237" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/firstOrError.png" alt="">
 * <dl>
 *  <dt><b>Backpressure:</b></dt>
 *  <dd>The operator honors backpressure from downstream and consumes the source {@code Publisher} in an
 *  unbounded manner (i.e., without applying backpressure).</dd>
 *  <dt><b>Scheduler:</b></dt>
 *  <dd>{@code firstOrError} does not operate by default on a particular {@link Scheduler}.</dd>
 * </dl>
 *
 * @return the new Single instance
 * @see <a href="http://reactivex.io/documentation/operators/first.html">ReactiveX operators documentation: First</a>
 */
@CheckReturnValue
@BackpressureSupport(BackpressureKind.SPECIAL) // take may trigger UNBOUNDED_IN
@SchedulerSupport(SchedulerSupport.NONE)
public final Single<T> firstOrError() {
  return elementAtOrError(0);
}

代码示例来源：origin: ReactiveX/RxJava

@Test
public void elementAtOrErrorIndex1OnEmptySource() {
  Flowable.empty()
    .elementAtOrError(1)
    .test()
    .assertFailure(NoSuchElementException.class);
}

代码示例来源：origin: ReactiveX/RxJava

@Test
public void elementAtOrErrorError() {
  Flowable.error(new RuntimeException("error"))
    .elementAtOrError(0)
    .test()
    .assertNoValues()
    .assertErrorMessage("error")
    .assertError(RuntimeException.class);
}

代码示例来源：origin: ReactiveX/RxJava

@Test
public void elementAtOrErrorOneElement() {
  Flowable.just(1)
    .elementAtOrError(0)
    .test()
    .assertNoErrors()
    .assertValue(1);
}

代码示例来源：origin: ReactiveX/RxJava

@Test
public void elementAtOrErrorNoElement() {
  Flowable.empty()
    .elementAtOrError(0)
    .test()
    .assertNoValues()
    .assertError(NoSuchElementException.class);
}

代码示例来源：origin: ReactiveX/RxJava

@Test
public void elementAtOrErrorMultipleElements() {
  Flowable.just(1, 2, 3)
    .elementAtOrError(1)
    .test()
    .assertNoErrors()
    .assertValue(2);
}

代码示例来源：origin: ReactiveX/RxJava

@Test
public void elementAtOrErrorInvalidIndex() {
  Flowable.just(1, 2, 3)
    .elementAtOrError(3)
    .test()
    .assertNoValues()
    .assertError(NoSuchElementException.class);
}