Blogger - FPOWJPWB - Retry in Scala

object retry {
  def apply[Result](operation: () => Result,
                    checker: Result => Boolean,
                    preRetry: () => Any = null,
                    times: Int = 1,
                    errorMessage: String = "Retries exhausted"): Result = {
    val (operationResult, operationException): (Result, Exception) = try {
      (operation(), null)
    } catch {
      case e: Exception => (null, e)
    }

    if (operationException == null && checker(operationResult))
      operationResult
    else {
      if (times > 0) {
        if (preRetry != null) preRetry()
        apply(operation, checker, preRetry, times - 1, errorMessage)
      } else
        throw
          if (operationException != null) operationException else new Exception(errorMessage)
    }
  }
}