如何对Stream.findNth（）进行编码？

本文介绍了如何对Stream.findNth（）进行编码？的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

与 Stream.findFirst（）类似，有没有办法写 Stream.findNth（）？

Similar to Stream.findFirst(), is there a way to write Stream.findNth()?

我正在通过重写一些遗留代码来练习Java 8。而且，我想知道如何使用Stream API编写以下函数。

I'm practicing Java 8 by rewriting some legacy code. And, I'm wondering how the below function can be written using Stream API.

static curPipeNumber = 0; /** skipToEntry() updates 'curPipeNumber' to 'pipeNumber' and returns the first byte position of the word before the ('pipeNumber')-th pipe. * It does so by reading and ignoring unnecessary bytes from the buffer. * e.g., */ static int skipToEntry(byte[] buf, int len, int nextByteToBeRead, int pipeNumber) { if(curPipeNumber == pipeNumber) return nextByteToBeRead; for(; nextByteToBeRead < len; nextByteToBeRead++) { if(buf[nextByteToBeRead] == '|') { ++curPipeNumber; if(curPipeNumber == pipeNumber) { return ++nextByteToBeRead; } } } return nextByteToBeRead; }

我希望它能转化为：

static int skipToEntry(byte[] buf, int len, int nextByteToBeRead, int pipeNumber) { if(curPipeNumber == pipeNumber) return nextByteToBeRead; OptionalInt pipeIndex = IntStream.range(i, len) .filter(n -> buf[n] == '|') .findNth(pipeNumber); curPipeNumber = pipeNumber; nextByteToBeRead = pipeIndex.getAsInt() + 1; return nextByteToBeRead; }

推荐答案

OptionalInt result = stream.skip(n-1).findFirst();