In Scala, launch Java Threads that stay alive forever

Recently I needed to spawn threads to have several Kafka consumers listening from a list of topics. I tried to do this using foreach from a parallel collection but it did not work. In the end I just used a for comprehension to launch a Java Thread for each Kafka consumer. Bellow is a synthesis of the code I used:

import scala.annotation.tailrec
import scala.util.Random

val is: Seq[Int] = 1 to 100

@tailrec
def printToScreen(i: Int): Unit = {
    println(i)
    Thread.sleep(1000 * Random.nextInt(10))
    printToScreen(i)
}

for (i: Int <- is) {
    val thread: Thread = new Thread {
        override def run {
            printToScreen(i)
        }
    }
    thread.start()
}

In the production code I have a list of Kafka consumers configurations and prinToScreen generates a call back that I send to the Kafka consumer.

The code above lunches 100 Threads and prints its corresponding number in random intervals.

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