How to use the Numeric/Integral typeclasses in Scala

IntegralStub.scala

package com.example.stubs

import scala.Integral.Implicits._
import scala.Ordering.Implicits._

abstract class NumericStub[N : Integral] {
  /**
   * Returns the next pseudo-random number of type `N`.
   */
  def nextRandom(): N

  /**
   * Returns the next pseudo-random number of type `N`
   * between zero (inclusive) and `upperBound` (exclusive).
   */
  def nextRandom(upperBound: N): N

  def randomPositive: N = nextRandom().abs

  def randomInRange(low: N, high: N): N = {
    // Integral extends Numeric, which extends Ordering. Therefore,
    // comparison operators are automatically available.
    require(low < high)
    val random = randomPositive
    // Numeric provides +, -, *, …
    val rangeLength = high - low
    // Integral provides / and %
    val selectedInRangeLength = random % rangeLength
    low + selectedInRangeLength
  }
}

IntStub.scala

package com.example.stubs

import scala.util.Random

object IntStub extends IntegralStub[Int] {
  override def nextRandom(): Int = Random.nextInt()
  override def nextRandom(upperBound: Int): Int = Random.nextInt(upperBound)
}

LongStub.scala

package com.example.stubs

import scala.util.Random

object LongStub extends IntegralStub[Long] {
  override def nextRandom(): Long = Random.nextLong()
  // HACK: This can be done better
  override def nextRandom(upperBound: Long): Long = IntStub.nextRandom(upperBound.toInt).toLong
}