Question

我是scala的新手。我想知道是否有更好的方法可以更好地编写以下if-else语句。这纯粹是我的学习

val tokenizationRequired = if (args(4).equals("true")) true else false

    if (tokenizationRequired) {
      primary_key                   = args(5)

      if (primary_key.equals("") || primary_key.isEmpty) {
        log info s"Primary_Key cannot be empty"
      }

      lookupPath                    = args(6)

      if (lookupPath.equals("") || lookupPath.isEmpty) {
        log info s"lookupPath cannot be empty"
      }

    }

这是我尝试过的无效案例

val primary_key = args(5) match {
        case " " => log info s"lookupPath cannot be empty"
        case _ => args(5)
 }

感谢您的帮助。

Answer 1

val tokenizationRequired = args(4).toBoolean
val primary_key                   = args(5)
val lookupPath                    = args(6)

if (tokenizationRequired && primary_key.isEmpty) {
  log info s"Primary_Key cannot be empty"
}

if (tokenizationRequired && lookupPath.isEmpty) {
  log info s"lookupPath cannot be empty"
}

这是我尝试过的无效的案例陈述...

这仅在scala 2.13中有效：

import scala.util.chaining._

val primary_key = arg(5)
     .tap(x => if (x.isEmpty) log info s"lookupPath cannot be empty")

，您的版本将使用此修复程序进行编译：

val primary_key = args(5) match {
  case x if x.isEmpty => 
    log info s"lookupPath cannot be empty"
    x
  case x => x 
}

否则，在单个语句中：scala

1 个答案: