Loom on Scala

[Eric Kolotyluk]

package net.kolotyluk.loom

import java.util.concurrent.StructuredExecutor
import scala.util.Using

object HelloScala {
  def main(args: Array[String]) {
    Context.printHeader(HelloScala.getClass)

    Using.Manager { use => // Scala's version of try-with-resources
      val structuredExecutor = use(StructuredExecutor.open("HelloScala"))

      val futureResults = (0 to 15).map{ item =>
        println(s"item = $item, Thread ID = ${Thread.currentThread}")
        structuredExecutor.fork{ () =>
          println(s"\ttask = $item, Thread ID = ${Thread.currentThread}")
          item
        }
      }
      println(futureResults.map(_.get))
      structuredExecutor.join
    }
  }
}

Yes, Loom does run on Scala 2.13... I cannot get Scala 3 to work with Maven
yet... might have to resort to SBT... ��

I wonder if ScopeLocal works correctly in Scala? �� I guess it should...

Don't have to worry about lazy Stream termination here ��

Don't need Future::resultNow either

For some reason, if you don't call join(), close() does not throw an
exception �� -- that's not right?

The Kotlin version was much harder to write and I will post later...

A fun way to end the week... ��

Cheers, Eric


"C:\Program Files (Open)\jdk-18\bin\java.exe" --enable-preview
-Dfile.encoding=windows-1252 -jar
C:\Users\ERIC\Documents\git\loom-lab\laboratory\target\laboratory.jar
Hello net.kolotyluk.loom.HelloScala$
PID       = 23312
CPU Cores = 12
Heap Size = 6442450944 bytes
______________________________________________________________________________

item = 0, Thread ID = Thread[#1,main,5,main]
item = 1, Thread ID = Thread[#1,main,5,main]
item = 2, Thread ID = Thread[#1,main,5,main]
item = 3, Thread ID = Thread[#1,main,5,main]
item = 4, Thread ID = Thread[#1,main,5,main]
item = 5, Thread ID = Thread[#1,main,5,main]
item = 6, Thread ID = Thread[#1,main,5,main]
item = 7, Thread ID = Thread[#1,main,5,main]
item = 8, Thread ID = Thread[#1,main,5,main]
item = 9, Thread ID = Thread[#1,main,5,main]
item = 10, Thread ID = Thread[#1,main,5,main]
item = 11, Thread ID = Thread[#1,main,5,main]
item = 12, Thread ID = Thread[#1,main,5,main]
     task = 0, Thread ID =
VirtualThread[#15]/runnable at ForkJoinPool-1-worker-1
item = 13, Thread ID = Thread[#1,main,5,main]
item = 14, Thread ID = Thread[#1,main,5,main]
     task = 1, Thread ID =
VirtualThread[#17]/runnable at ForkJoinPool-1-worker-2
     task = 2, Thread ID =
VirtualThread[#18]/runnable at ForkJoinPool-1-worker-3
     task = 4, Thread ID =
VirtualThread[#20]/runnable at ForkJoinPool-1-worker-3
     task = 5, Thread ID =
VirtualThread[#22]/runnable at ForkJoinPool-1-worker-2
     task = 7, Thread ID =
VirtualThread[#24]/runnable at ForkJoinPool-1-worker-2
     task = 6, Thread ID =
VirtualThread[#23]/runnable at ForkJoinPool-1-worker-3
     task = 8, Thread ID =
VirtualThread[#25]/runnable at ForkJoinPool-1-worker-3
     task = 9, Thread ID =
VirtualThread[#27]/runnable at ForkJoinPool-1-worker-2
     task = 3, Thread ID =
VirtualThread[#19]/runnable at ForkJoinPool-1-worker-4
     task = 10, Thread ID =
VirtualThread[#28]/runnable at ForkJoinPool-1-worker-3
     task = 11, Thread ID =
VirtualThread[#29]/runnable at ForkJoinPool-1-worker-2
     task = 12, Thread ID =
VirtualThread[#31]/runnable at ForkJoinPool-1-worker-4
     task = 13, Thread ID =
VirtualThread[#34]/runnable at ForkJoinPool-1-worker-5
item = 15, Thread ID = Thread[#1,main,5,main]
     task = 14, Thread ID =
VirtualThread[#35]/runnable at ForkJoinPool-1-worker-5
     task = 15, Thread ID =
VirtualThread[#42]/runnable at ForkJoinPool-1-worker-11
Vector(0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15)

Process finished with exit code 0