用于正则表达式模式匹配的 Scala 代码

Question

我是 Scala 新手。我正在尝试正则表达式模式匹配。我正在按照此处的示例进行操作：https://alvinalexander.com/scala/how-to-extract-parts-strings-match-regular-expression-regex-scala

下面给出的是我编写的有效代码，但显然不是最好的方法。
场景：我有一个正则表达式模式。

"([a-z0-9]+)_([0-9]+)_([v|V][0-9]+)_(\d{4})(\d{2})(\d{2}).(xls|xlsx)".r

我有一个字符串，它定义了我对给定场景的期望。
val param = "manufacturer/order/version"

问题：我不想在 case pattern(manufacturer, order, version) 中传递硬编码值，而是在变量 manufacturer, order 和 version 中得到输出？一种方法是最初定义所有变量，但这意味着每次我需要更改字符串时都要更改代码。有没有办法动态地做到这一点或在 scala 中使用正则表达式的更好方法。

package com.testing

class DynamicFolder() {

  def dynamicPath(fileName: String): Map[String, String] = { 
    println("File Name: " + fileName)

    val param = "manufacturer/order/version"

    var patternString = param.replaceAll("/", ", ")
    println(patternString)

    val pattern = "([a-z0-9]+)_([0-9]+)_([v|V][0-9]+)_(\d{4})(\d{2})(\d{2}).(xls|xlsx)".r
    val paramMap: Map[String, String] = fileName match {
      case pattern(manufacturer, order, version) => {
        println(s"Manufacturer: $manufacturer, Order: $order, version: $version")
        Map("manufacturer" -> manufacturer, "order" -> order, "version" -> version)
      }

      case pattern(manufacturer, order, version, yyyy, mm, dd, format) => {
        println(s"Manufacturer: $manufacturer, Order: $order, version: $version")
        Map("manufacturer" -> manufacturer, "order" -> order, "version" -> version)
      }

      case _ => throw new IllegalArgumentException
    }  
    paramMap
  }
}

object hello {

  def main(args: Array[String]): Unit = {
    var dynamicFolder = new DynamicFolder

    val fileName = "man1_18356_v1_20180202.xls"
    val tgtParams = dynamicFolder.dynamicPath(fileName)
    var tgtPath = "" 
    for ((k, v) <- tgtParams) {
      printf("key: %s, value: %s\n", k, v)
      tgtPath = tgtPath + "/" + tgtParams(k)
    }

    println ("Target path: "+tgtPath)
  }
}

代码输出：

文件名：man1_18356_v1_20180202.xls
制造商、版本、订单
制造商：man1，订单：18356，版本：v1
键：制造商，值：man1
键：顺序，值：18356
键：版本，值：v1
目标路径：/man1/18356/v1

谢谢！

Answer 1

这是您收集所有组并自行处理它们的方法：

val paramMap: Map[String, String] = fileName match {
    case pattern(groups@_*) if groups.nonEmpty => {
        // Access group with groups(0), groups(1) etc.
    }

    case _ => throw new IllegalArgumentException
}

用于正则表达式模式匹配的 Scala 代码

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