本文整理了Java中io.reactivex.Observable.elementAtOrError()方法的一些代码示例，展示了Observable.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。Observable.elementAtOrError()方法的具体详情如下：
包路径：io.reactivex.Observable
类名称：Observable
方法名：elementAtOrError

Observable.elementAtOrError介绍

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

Scheduler: elementAtOrError does not operate by default on a particular Scheduler.
[中]返回一个单一元素，该元素在该可观测元素的一系列发射中的指定索引处发现，或者如果该可观测元素的信号元素少于索引元素，则表示无接触元素异常。
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 Observable or
 * signals a {@link NoSuchElementException} if this Observable is empty.
 * <p>
 * <img width="640" height="434" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/firstOrError.o.png" alt="">
 * <dl>
 *  <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
@SchedulerSupport(SchedulerSupport.NONE)
public final Single<T> firstOrError() {
  return elementAtOrError(0L);
}

代码示例来源：origin: redisson/redisson

/**
 * Returns a Single that emits only the very first item emitted by this Observable or
 * signals a {@link NoSuchElementException} if this Observable is empty.
 * <p>
 * <img width="640" height="434" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/firstOrError.o.png" alt="">
 * <dl>
 *  <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
@SchedulerSupport(SchedulerSupport.NONE)
public final Single<T> firstOrError() {
  return elementAtOrError(0L);
}

代码示例来源：origin: ReactiveX/RxJava

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

代码示例来源：origin: ReactiveX/RxJava

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

代码示例来源：origin: ReactiveX/RxJava

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

代码示例来源：origin: ReactiveX/RxJava

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

代码示例来源：origin: ReactiveX/RxJava

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

代码示例来源：origin: ReactiveX/RxJava

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