PrefetchableIterators (fn-execution 2.44.0 API)

java.lang.Object
- org.apache.beam.sdk.fn.stream.PrefetchableIterators

public class PrefetchableIterators
extends java.lang.Object

Constructor Summary

Constructors
Constructor Description

PrefetchableIterators()

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method	Description
`static <T> PrefetchableIterator<T>`	`concat(java.util.Iterator<T>... iterators)`	Concatentates the `Iterator`s.
`static <T> PrefetchableIterator<T>`	`concatIterators(java.util.Iterator<java.util.Iterator<T>> iterators)`
`static <T> PrefetchableIterator<T>`	`emptyIterator()`	Returns an empty `PrefetchableIterator`.
`static <T> PrefetchableIterator<T>`	`fromArray(T... values)`	Returns a `PrefetchableIterator` over the specified values.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - PrefetchableIterators
```
public PrefetchableIterators()
```
- Method Detail
  - emptyIterator
```
public static <T> PrefetchableIterator<T> emptyIterator()
```
    Returns an empty PrefetchableIterator.
  - fromArray
```
public static <T> PrefetchableIterator<T> fromArray(T... values)
```
    Returns a PrefetchableIterator over the specified values.
    PrefetchableIterator.prefetch() is a no-op and PrefetchableIterator.isReady() always returns true.
  - concatIterators
```
public static <T> PrefetchableIterator<T> concatIterators(java.util.Iterator<java.util.Iterator<T>> iterators)
```
  - concat
```
public static <T> PrefetchableIterator<T> concat(java.util.Iterator<T>... iterators)
```
    Concatentates the Iterators.
    Iterables are first converted into a PrefetchableIterable via maybePrefetchable(java.util.Iterator<T>).
    The returned PrefetchableIterable ensures that iterators which are returned guarantee that PrefetchableIterator.isReady() always advances till it finds an Iterable that is not PrefetchableIterator.isReady(). PrefetchableIterator.prefetch() is also guaranteed to advance past empty iterators till it finds one that is not ready.