java - Spliterator Java 8 - 自定义实现

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我正在学习这个 Java 8 功能，但我真的发现很难理解 Spliterator接口(interface)的trySplit()自定义类的方法实现用于并行处理生成的Stream .

有人可以帮我提供一些带有清晰示例的好教程吗？

Answer 1

An ideal trySplit method efficiently (without traversal) divides its elements exactly in half, allowing balanced parallel computation. Many departures from this ideal remain highly effective; for example, only approximately splitting an approximately balanced tree, or for a tree in which leaf nodes may contain either one or two elements, failing to further split these nodes. However, large deviations in balance and/or overly inefficient trySplit mechanics typically result in poor parallel performance.

以及带注释的方法结构

 public Spliterator<T> trySplit() {
   int lo = origin; // divide range in half
   int mid = ((lo + fence) >>> 1) & ~1; // force midpoint to be even
   if (lo < mid) { // split out left half
     origin = mid; // reset this Spliterator's origin
     return new TaggedArraySpliterator<>(array, lo, mid);
   }
   else       // too small to split
     return null;
 }

欲了解更多信息，请阅读 https://docs.oracle.com/javase/8/docs/api/java/util/Spliterator.html