Develop Reference

java.nio.ByteBuffer wrap method partly working with sbt run

I have an issue where I read a bytestream from a big file ~ (100MB) and after some integers I get the value 0 (but only with sbt run ). When I hit the play button on IntelliJ I get the value I expected > 0.
My guess was that the environment is somehow different. But I could not spot the difference.
// DemoApp.scala
import java.nio.{ByteBuffer, ByteOrder}
object DemoApp extends App {
val inputStream = getClass.getResourceAsStream("/HandRanks.dat")
val handRanks = new Array[Byte](inputStream.available)
inputStream.read(handRanks)
inputStream.close()
def evalCard(value: Int) = {
val offset = value * 4
println("value: " + value)
println("offset: " + offset)
ByteBuffer.wrap(handRanks, offset, handRanks.length - offset).order(ByteOrder.LITTLE_ENDIAN).getInt
}
val cards: List[Int] = List(51, 45, 14, 2, 12, 28, 46)
def eval(cards: List[Int]): Unit = {
var p = 53
cards.foreach(card => {
println("p = " + evalCard(p))
p = evalCard(p + card)
})
println("result p: " + p);
}
eval(cards)
}
The HandRanks.dat can be found here: (I put it inside a directory called resources)
https://github.com/Robert-Nickel/scala-texas-holdem/blob/master/src/main/resources/HandRanks.dat
build.sbt is:
name := "LoadInts"
version := "0.1"
scalaVersion := "2.13.4"
On my windows machine I use sbt 1.4.6 with Oracle Java 11
You will see that the evalCard call will work 4 times but after the fifth time the return value is 0. It should be higher than 0, which it is when using IntelliJ's play button.

You are not reading a whole content. This
val handRanks = new Array[Byte](inputStream.available)
allocates only as much as InputStream buffer and then you read the amount in buffer with
inputStream.read(handRanks)
Depending of defaults you will process different amount but they will never be 100MB of data. For that you would have to read data into some structure in the loop (bad idea) or process it in chunks (with iterators, stream, etc).
import scala.util.Using
// Using will close the resource whether error happens or not
Using(getClass.getResourceAsStream("/HandRanks.dat")) { inputStream =>
def readChunk(): Option[Array[Byte]] = {
// can be done better, but that's not the point here
val buffer = new Array[Byte](inputStream.available)
val bytesRead = inputStream.read(buffer)
if (bytesRead >= 0) Some(buffer.take(bytesRead))
else None
}
#tailrec def process(): Unit = {
readChunk() match {
case Some(chunk) =>
// do something
process()
case None =>
// nothing to do - EOF reached
}
}
process()
}

JavaFX MediaPlayer: MP4 loop freeze, sound distorted, Windows 7

We have a problem with JavaFX MediaPlayer for more than a month now. We read and tried all the similar problems here, nothing worked.
Simplest example: It's an info app with 2 videos from a folder played continualy in a loop. After some time (sometimes 2h, sometimes 2 days)
videos start to slow down, duration is longer, occasional freeze, sound becomes distorted.
OS: win7 64b (Ultimate) SP1
Intel Celeron CPU N3150 #1.6GHz
8 GB Ram
java 1.8 and 1.10, 64b
Tried:
OS update, latest.
Drivers updates, other drivers.
JDK 64b, 1.8 latest updates, JDK 1.10 latest.
Changing code (adding dispose, closing, setting null, caching... every suggestion on stackoverflow)
Changing video encoders: MPEG-4, H.264 and H.264-HD, 1500/2000/4000/8000 kbps, 25fps
Changing resolutions: 1280x720,
Sound: AAC, 1 and 2 channels, 48 & 44 kHz, 128kbps bit rate and others. Tried videos without audio.
Almost every possible combination of these video/sound encoders, bitrates, resolutions, framerates ...
We profiled for memory leaks: memory grows for some time and it stops growing. It's ok (we think).
Nothing we tried has worked. No errors, no exceptions on MediaView, Media, Player. No system events.
Confusing: we noticed that that in normal operations CPU is 20-30%, but, when videos start to freeze, it's lower, 5-15%.
Code (latest version):
import java.io.File
import akka.actor.{Actor, ActorLogging, Props, Timers}
import akka.pattern._
import com.commercial.activity.MMDriver.ShowNextMedia
import javafx.event.EventHandler
import javafx.scene.media.{Media, MediaErrorEvent, MediaPlayer, MediaView}
import scala.concurrent.ExecutionContext.Implicits.global
import scala.concurrent.Future
object MMDriver {
def props(rootFolder: File, allowedExtension: List[String],
showMedia: (MMedia) => Unit): Props = Props(new MMDriver(rootFolder, allowedExtension, showMedia))
case object Start
case class MediaCreated(list: List[MMedia])
case object ShowNextMedia
}
class MMDriver(rootFolder: File, allowedExtensions: List[String],
showMedia: (MMedia) => Unit) extends Actor with ActorLogging with Timers {
object TimerKey
var started = false
var medias = List[MMedia]()
var index = 0
override def receive: Receive = {
case MMDriver.Start if (!started) =>
started = true
Future {
loadMedia(rootFolder, allowedExtensions)
.map { file =>
val media = new Media(file.toURI.toURL.toString)
val player = new MediaPlayer(media)
//next video
player.setOnEndOfMedia(new Runnable {
override def run(): Unit = {
self ! ShowNextMedia
}
})
val mediaView = new MediaView(player)
setErrorHandlers(player, media, mediaView)
MMedia(file, media, player, mediaView)
}
}
.map(media => MMDriver.MediaCreated(media.toList))
.pipeTo(self)
case MMDriver.MediaCreated(list) =>
medias = list
if (medias.nonEmpty) {
self ! ShowNextMedia
}
case MMDriver.ShowNextMedia =>
val media = medias(index)
showMedia(media)
index = index + 1
index = index % medias.size
case msg =>
log.info("not processed message {}", msg)
}
private def loadMedia(folder: File, allowedExtensions: List[String]): Array[File] = {
folder.listFiles()
.filter { file =>
allowedExtensions.exists(file.getName.endsWith(_))
}
}
private def setErrorHandlers(player: MediaPlayer, media: Media, mediaView: MediaView): Unit = {
player.setOnError(new Runnable {
override def run(): Unit = {
log.error(player.getError, "error in player")
}
})
media.setOnError(new Runnable {
override def run(): Unit = {
log.error(media.getError, "error in media")
}
})
mediaView.setOnError(new EventHandler[MediaErrorEvent] {
override def handle(event: MediaErrorEvent): Unit = {
log.error(event.getMediaError, "error in mediaView")
}
})
}
}
Any suggestion what to try next - we are out of ideas?!

Schedule next run time is incorrect

I have a simple Schedule like below which should run every 30 minutes from 6pm to 10:30pm.
import javax.ejb.Schedule;
import javax.ejb.Schedules;
import javax.ejb.Singleton;
#Singleton
public class XxxJob {
#Schedules({
#Schedule(minute = "0,30", hour = "18-22", dayOfWeek = "Mon-Fri",
timezone = "Europe/London", persistent = false)
})
public void process() {
//...
}
}
But when I check the details of the timer on the Wildfly console, I see this:
{"time-remaining" => 30039141L,"next-timeout" => 1498757400000L,"calendar-timer" => true,"persistent" => false,"schedule" => {"year" => "*","month" => "*","day-of-month" => "*","day-of-week" => "Mon-Fri","hour" => "18-22","minute" => "0,30","second" => "0","timezone" => "Europe/London","start" => undefined,"end" => undefined}}
It says the next run (next-timeout) is at 1498757400000L (epoch millis) but that corresponds to 2017-06-29T18:30+01:00[Europe/London] and not 18:00.
Why is the timer scheduled to run at 18:30 and not at 18:00?
Note 1: if I amend the schedule to only run at 18:00 it works as expected:
#Schedule(minute = "0", hour = "18", dayOfWeek = "Mon-Fri",
timezone = "Europe/London", persistent = false)
Note 2: if I remove the #Schedules annotation it works as expected too.

Number format exception in scala

I am trying to write a scala program to generate an output file omega0_Real.txt which contains pre-calculated values of the cosine function for inputs ranging from 0 to pi/2 radians. Each of these calculated values are 72 bit long and are stored in hex format. The code I have written so far is as follows:
import java.io._
import scala.math._
object omega0_Real {
def main (args: Array[String]) {
val arg = (0.0).to(2-pow(2, -10), pow(2, -10))
val cosArg = arg.map (i => cos(i))
val cosBit = cosArg.map (i => List.tabulate(72)(j = (BigDecimal((i*pow(2,j))).toBigInt % 2)))
val cosStr = cosBit.map (i => i mkString)
val cosBig = cosStr.map (i => BigInt(i, 2))
val cosBigStr = cosBig.map (i => i.toString(16))
val cosList = cosBigStr.toList
val file = "omega0_Real.txt"
val writer = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(file)))
for (x <- cosList) {
writer.write(x + "\n")
}
writer.close()
}
which gives the error: java.lang.NumberFormatException: Illegal embedded sign character followed by many others. Please help me debug this code.
PS: I ran this code line-by-line on sbt console but it did not give any error, although the values generated were erroneous.

Processing CQEngine ResultSet with Scala foreach is very slow

I'm trying to process CQEngine's ResultSet using Scala's foreach, but the result is very slow.
Following is the snippet of what I'm trying to do
import collection.JavaConversions._
val query = existIn(myOtherCollection, REFERENCE, REFERENCE)
val resultSet = myIndexCollection.retrieve(query)
resultSet.foreach(r =>{
//do something here
})
Somehow the .foreach method is very slow. I tried to debug by putting SimonMonitor and change the .foreach using while(resultSet.hasNext), surprisingly, every call to hasNext method takes about 1-2 seconds. That's very slow.
I tried to create the same version using Java, and the Java version is super fast.
Please help

I am not able to reproduce your problem with the below test code. Can you try it on your system and let me know how it runs?
(Uncomment line 38, garages.addIndex(HashIndex.onAttribute(Garage.BRANDS_SERVICED)), to make BOTH the Scala and Java iterators run blazingly fast...)
The output first (time in milliseconds):
Done adding data
Done adding index
============== Scala ==============
Car{carId=4, name='BMW M3', description='2013 model', features=[radio, convertible]}
Time : 3 seconds
Car{carId=1, name='Ford Focus', description='great condition, low mileage', features=[spare tyre, sunroof]}
Time : 1 seconds
Car{carId=2, name='Ford Taurus', description='dirty and unreliable, flat tyre', features=[spare tyre, radio]}
Time : 2 seconds
============== Java ==============
Car{carId=4, name='BMW M3', description='2013 model', features=[radio, convertible]}
Time : 3 seconds
Car{carId=1, name='Ford Focus', description='great condition, low mileage', features=[spare tyre, sunroof]}
Time : 1 seconds
Car{carId=2, name='Ford Taurus', description='dirty and unreliable, flat tyre', features=[spare tyre, radio]}
Time : 2 seconds
Code below:
import collection.JavaConversions._
import com.googlecode.cqengine.query.QueryFactory._
import com.googlecode.cqengine.CQEngine;
import com.googlecode.cqengine.index.hash._;
import com.googlecode.cqengine.IndexedCollection;
import com.googlecode.cqengine.query.Query;
import java.util.Arrays.asList;
object CQTest {
def main(args: Array[String]) {
val cars: IndexedCollection[Car] = CQEngine.newInstance();
cars.add(new Car(1, "Ford Focus", "great condition, low mileage", asList("spare tyre", "sunroof")));
cars.add(new Car(2, "Ford Taurus", "dirty and unreliable, flat tyre", asList("spare tyre", "radio")));
cars.add(new Car(3, "Honda Civic", "has a flat tyre and high mileage", asList("radio")));
cars.add(new Car(4, "BMW M3", "2013 model", asList("radio", "convertible")));
// add cruft to try and slow down CQE
for (i <- 1 to 10000) {
cars.add(new Car(i, "BMW2014_" + i, "2014 model", asList("radio", "convertible")))
}
// Create an indexed collection of garages...
val garages: IndexedCollection[Garage] = CQEngine.newInstance();
garages.add(new Garage(1, "Joe's garage", "London", asList("Ford Focus", "Honda Civic")));
garages.add(new Garage(2, "Jane's garage", "Dublin", asList("BMW M3")));
garages.add(new Garage(3, "John's garage", "Dublin", asList("Ford Focus", "Ford Taurus")));
garages.add(new Garage(4, "Jill's garage", "Dublin", asList("Ford Focus")));
// add cruft to try and slow down CQE
for (i <- 1 to 10000) {
garages.add(new Garage(i, "Jill's garage", "Dublin", asList("DONT_MATCH_CARS_BMW2014_" + i)))
}
println("Done adding data")
// cars.addIndex(HashIndex.onAttribute(Car.NAME));
// garages.addIndex(HashIndex.onAttribute(Garage.BRANDS_SERVICED));
println("Done adding index")
val query = existsIn(garages, Car.NAME, Garage.BRANDS_SERVICED, equal(Garage.LOCATION, "Dublin"))
val resultSet = cars.retrieve(query)
var previous = System.currentTimeMillis()
println("============== Scala ============== ")
// Scala version
resultSet.foreach(r => {
println(r);
val t = (System.currentTimeMillis() - previous)
System.out.println("Time : " + t / 1000 + " seconds")
previous = System.currentTimeMillis()
})
println("============== Java ============== ")
previous = System.currentTimeMillis()
// Java version
val i: java.util.Iterator[Car] = resultSet.iterator()
while (i.hasNext) {
val r = i.next()
println(r);
val t = (System.currentTimeMillis() - previous)
System.out.println("Time : " + t / 1000 + " seconds")
previous = System.currentTimeMillis()
}
}
}