Future

Transcript

1. 'VUVSF 4IJHFLJ
   4IPKJ

2. r4DBMBεέʔϥϒϧϓϩάϥϛϯά lεϨουɺϩοΫɺϞχλʔͳͲ͸ɺσουϩοΫ ͱڝ߹ͷ஍ཕݪͰ͋Δz

3. +BWB
   'VUVSF w +BWB
   
   ͔Β͋Δɺ'VUVSF
   ͸஋ΛऔΓग़͢ͱ͖ɺඇಉظ ܭࢉͷ݁ՌΛHFUϝιουͰऔಘ͢Δɻ͜ͷͱ͖ݺͼग़͠ ͍ͯΔεϨου͸ϒϩοΫ͞ΕΔɻܭࢉ݁ՌΛ࢖ͬͯ͞Β ʹܭࢉΛਐΊΔͨΊʹ͸ɺ׬ྃΛ଴ͭඞཁ͕͋Δɻ
 "84
   4%,
   GPS
   +BWB
   
   ܥͷ
   "TZOD
   ͸͜ͷ
   'VUVSF
   ͕ ࢖ΘΕ͍ͯΔɻ def process(jf:

   java.util.concurrent.Future[Int]): Int = { jf.get()

4. $PNQMFUBCMF'VUVSF w +BWB
   
   Ͱಋೖ͞Εͨ৽͍͠
   'VUVSFɻ UIFO"QQMZ 'VODUJPO
   UIFO"DDFQU $POTVNFS
   ͳͲΛ ࢖ͬͯɺϒϩοΫ͞ΕΔ͜ͱͳ͘ɺNPOBEJD
   ʹॲཧ͕ॻ ͚ΔΑ͏ʹͳͬͨɻ


   "84
   4%,
   GPS
   +BWB
   
   ͷ
   "TZOD
   Ͱ͸͜Ε͕࢖ΘΕΔɻ def process(cf: CompletableFuture[Int]) = { cf.thenApply(x => x * 2) .thenAccept(x => println(x)) }

5. 4DBMB
   ͷ
   'VUVSF w 4DBMB
   ͷ
   'VUVSF
   ͸
   $PNQMFUBCMF'VUVSF
   ಉ༷ʹϒϩοΫ ͞Εͳ͍ɻ def process(sf: scala.concurrent.Future[Int]) = { sf.map(x

   => x * 2) .map(x => x.toString) .foreach(str => println(str)) }

6. $PNQMFUBCMF'VUVSF
   
   4DBMB
   'VUVSF w PSHTDBMBMBOHNPEVMFTTDBMBKBWBDPNQBUΛ࢖͏͜ ͱͰɺUP+BWB
   UP4DBMB
   Ͱ
   $PNQMFUBCMF'VUVSF $PNQMFUBCMF4UBHF
   ͱ
   'VUVSF
   Λ ૬ޓʹม׵͢Δ͜ͱ͕Ͱ͖Δ def

   convert[T](cf: CompletableFuture[T]): scala.concurrent.Future[T] = cf.toScala def convert[T](cf: scala.concurrent.Future[T]): CompletionStage[T] = cf.toJava

7. ࢭ·Βͳ͍

8. w εϨου͕͍͖͚ͭͮΔ object Examples extends App { val es =

   Executors.newCachedThreadPool() implicit val ec = ExecutionContext.fromExecutorService(es) val future = scala.concurrent.Future { Thread.sleep(5000) println("running") () } println("end") future.onComplete(x => x.fold(ex => ex.printStackTrace(), _ => println("success"))) }

9. object Examples extends App { val es = Executors.newCachedThreadPool() implicit

   val ec = ExecutionContext.fromExecutorService(es) val future = scala.concurrent.Future { Thread.sleep(5000) println("running") () } println("end") future.onComplete(_ => es.shutdown()) }

10. ϑϦʔζ

11. w &YFDVUJPO$POUFYU*NQMJDJUTHMPCBM΍"LLBͷEFGBVMU EJTQBUDIFS౳͸ɺ'PSL+PJO1PPM͕࢖༻͞ΕΔɻ
    w 'PSL+PJO1PPM͸ଞͷछྨͷ&YFDVUPS4FSWJDFͱҟͳΓ XPSLTUFBMJOHΛ࢖༻͢Δɻ
    w ϒϩοΩϯάॲཧ౳͕͋Δͱɺ଴ػதʹଞͷλεΫͷͨΊ ʹεϨουΛ࢖༻͢Δ͜ͱ͕Ͱ͖ͳ͘ͳΔͨΊɺσου ϩοΫΛى͜͢͜ͱ͕͋Δɻ

12. w ϒϩοΩϯά*0౳͚ͩͰͳ࣍͘ͷΑ͏ͳίʔυ΋ϒϩοΫ ͕ൃੜ͢Δ def process(jf: java.util.concurrent.Future[Int]): Int = { jf.get()

    Thread.sleep(5000)

13. 5ISFBE
     5ISFBE
    

14. w 'PSL+PJO1PPMͷεϨου͕͔ͭ͠ͳ͍৔߹ɺԼͷίʔ υ͸ɺKG
    Λ࣮ߦ͢ΔͨΊͷεϨουΛӬԕʹ଴ͭ͜ͱʹ ͳͬͯ͠·͏ val A = scala.concurrent.Future { val

    jf: java.util.concurrent.Future[Int] = ... jf.get() } val B = scala.concurrent.Future { while (true) { Thread.sleep(500) } } " # 5ISFBE
     5ISFBE
    

15. r4DBMBεέʔϥϒϧϓϩάϥϛϯά lʮϑϡʔνϟʔۭؒʯʹೖͬͨΒɺͰ͖ΔݶΓϑʔ νϟʔۭؒʹ͍ଓ͚ΔΑ͏ʹ͢΂͖ͩz ·ͱΊ

16. w "LLB
    ΍
    3FBDUJWF
    4USFBNTΛ࢖͏৔߹ʹ͸ɺϒϩοΩϯ ά͠ͳ͍Α͏ʹ͠·͠ΐ͏
    w 'VUVSFΛ࢖͏৔߹͸ɺ+BWB
    ͷ$PNQMFUBCMF'VUVSF΍ 4DBMBͷ'VUVSFΛ࢖͍·͠ΐ͏
    w "84
    4%,
    GPS
    +BWB
    ͸ɺ$PNQMFUBCMF'VUVSFΛฦ͢Α ͏ͳɺ4DBMBͷ'VUVSFʹม׵͢Δ͜ͱ͕Մೳͳ"1*Λ࢖͍ ·͠ΐ͏
    

    w ϒϩοΩϯά͕ඞཁͳ৔߹͸ɺ'PSL+PJO1PPMͰ͸ͳ͘ɺ 'JYFE5ISFBE1PPM౳ΛׂΓ౰ͯ·͠ΐ͏