JarCastingparallelizer 
A library offering tiny utilities for parallelization.
Installation
libraryDependencies += "com.github.takezoe" %% "parallelizer" % "0.0.6"
Usage
For example, each element of the source collection can be proceeded in parallel as the following example.
import com.github.takezoe.parallelizer.Parallel
val source: Seq[Int] = Seq(1, 2, 3)
// Run each element in parallel, but this call is blocked. Result order is preserved.
val result: Seq[Int] = Parallel.run(source){ i: Int =>
...
}
Parallelism can be specified as a second parameter. The default parallelism is a number of available processors.
// Run with 100 threads. Result order is preserved.
val result: Seq[Int] = Parallel.run(source, parallelism = 100){ i: Int =>
...
}
Parallel execution can be broken immediately by calling Parallel.break in the closure. It waits for the completion is ongoing elements, but drops all elements remaining when it called.
// Break parallel execution if terminated flag is true
val result: Seq[Int] = Parallel.run(source, parallelism = 100){ i: Int =>
if (terminated) {
Parallel.break
}
...
}
Implicit class which offers syntax sugar to use these methods easily is also available.
import com.github.takezoe.parallelizer._
val source: Seq[Int] = Seq(1, 2, 3)
source.parallelMap(parallelism = 2){ i: Int =>
...
}