skip()方法是短路操作吗?

问题描述

我正在阅读有关Java流的短路操作的信息，并且在某些文章中发现skip()是短路操作.

I am reading about Java streams' short-circuiting operations and found in some articles that skip() is a short-circuiting operation.

在另一篇文章中，他们没有提到skip()是短路操作.

In another article they didn't mention skip() as a short-circuiting operation.

现在我很困惑； skip()是不是短路操作?

Now I am confused; is skip() a short-circuiting operation or not?

推荐答案

从Java文档的流操作和管道"部分:

强调我的.

如果要在无限输入上调用skip，则不会产生有限的流，因此不是短路操作.

if you were to call skip on an infinite input it won't produce a finite stream hence not a short-circuiting operation.

JDK8 中唯一的短路中间操作是limit，因为它允许无限流上的计算在有限时间内完成.

The only short-circuiting intermediate operation in JDK8 is limit as it allows computations on infinite streams to complete in finite time.

示例:

如果要使用skip执行该程序:

if you were to execute this program with the use of skip:

String[] skip = Stream.generate(() -> "test") // returns an infinite stream
                      .skip(20) 
                      .toArray(String[]::new);

它不会产生 finite 流，因此您最终将得到类似于"java.lang.OutOfMemoryError:Java堆空间"的内容.

it will not produce a finite stream hence you would eventually end up with something along the lines of "java.lang.OutOfMemoryError: Java heap space".

而如果您要使用limit执行该程序，则会导致计算在finite时间内完成:

whereas if you were to execute this program with the use of limit, it will cause the computation to finish in a finite time:

String[] limit = Stream.generate(() -> "test") // returns an infinite stream
                       .limit(20)
                       .toArray(String[]::new);

这篇关于skip()方法是短路操作吗?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！