[Kotlin] Create secure random token

token.kt

import java.security.SecureRandom
import java.util.Base64

// Which is better?
val strong = SecureRandom.getInstanceStrong()
val sha1prng = SecureRandom.getInstance("SHA1PRNG")
println(strong.algorithm)
println(sha1prng.algorithm)

fun ByteArray.toHexString() = joinToString("") { "%02x".format(it) }

val bytes = ByteArray(64)
sha1prng.nextBytes(bytes)
println(bytes.toHexString())

val encoder = Base64.getUrlEncoder().withoutPadding()
val token = encoder.encodeToString(bytes)
println(token)