如何对Stream.findNth（）进行编码？

与Stream.findFirst()类似，有没有办法编写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。

 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. * eg, */ 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; } 

我希望它会转化为：

 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; } 

Answer 1

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