StreamsTest.scala

/*
Results
[info] Running StreamsExperiments 
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[info] Time: 3961
[info] 
[info] 
[info] ... scala.io.Source
[info] Count: 923062246
[info] Time: 1884
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[info] Time: 1696
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[info] Time: 1698
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[info] Time: 1694
[info] Count: 923062246
[info] Time: 1683
*/


import fs2.{io, Stream, text, Task}
import java.io._
import java.nio._
import java.nio.channels._
import java.nio.file._
import java.nio.charset._
import java.util.Scanner
import java.util.stream.{Stream => JStream}

import scala.io.Source

object StreamsExperiments extends App{


	val decoder = Charset.forName("UTF-8").newDecoder();

	var i = 0
	while(i < 10){
		val begin = System.currentTimeMillis
		val charCount: Task[Unit] =
		  io.file.readAll[Task](Paths.get("test-1GB.txt"), 1000000)
		  	.chunkLimit(1000000)
		  	.map{ chunk => 
		  		decoder.decode(
		  			ByteBuffer.wrap(chunk.toArray)
		  		).toString.split("\n")
		  	}
		  	.flatMap{ array => Stream.emits(array)}
		  	.fold(0L)(_ + _.length)
		    .map(count => println(s"Count: $count"))
		    .run
		charCount.unsafeRun	
		println(s"Time: ${System.currentTimeMillis - begin}")
		i = i + 1
	}
	
	
println("\n\n... scala.io.Source")

	i = 0
	while(i < 10){
		val begin = System.currentTimeMillis
		val count = Source.fromFile("test-1GB.txt")
			.getLines
			.foldLeft(0L)(_ + _.length)
		println(s"Count: $count")
		println(s"Time: ${System.currentTimeMillis - begin}")
		i = i + 1
	}

	
}