Javaの冗長な構文を愛でてみる / java-redundant-syntax

2020-10-04
J Lang Fest Kansai Online #1
https://kansai-jvm-langs-fest.connpass.com/event/188249/

Transcript

1. +BWBͷ৑௕ͳߏจΛ
   ѪͰͯΈΔ
   +-BOH'FTU,BOTBJ0OMJOF
   5
   !JSPG
   

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2. ओʹ+BWBΛ࢖͍ͬͯΔ;ͭ͏ͷϓϩάϥϚ
   ;ͭ͏ಛผͳ͜ͱ͸ͤͣɺ;ͭ͏ͷ͜ͱΛ;ͭ͏
   ʹ͢ΔɻͦΜͳҙਤͰ໊৐ͬͯ·͢ɻ
   ؔ੢+BWBΤϯδχΞͷձʢؔδϟόʣ͔Β͖·ͨ͠
   ݸਓࣄۀओ೥ੜ
   ͓࢓ࣄ͸௿֬౓ͷࡶஊ͔ΒͰ΋͓࢕͍ͯ͠·͢
   ࢓ࣄ͸+BWBͰͷ։ൃʹݶΒ͍ͣΖ͍ΖͰ͢
   

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3. ͸ͳ͢͜ͱ
   ࢲͱ+"7"
   +7.ͱ+BWBͷؔ܎
   +BWB͸৑௕ʁ
   ࢲ͕ࠓճ࿩͔ͨͬͨ͜͠ͱ
   

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4. ࢲͱ+"7"
   

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5. ࢲͱ+"7"
   ݱࡏ鱳KBWBDPN鱴鲿鲮鲜鳫鱑่鲑鱫鱉鲐ɻ
   鱭鱫鲇൵鱜
   鱉
   

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6. ࢲʹͱͬͯͷ+BWB
   ೥Ҏ্฼ࠃޠͱͯ͠࢖༻
   ೔ຊޠΑΓॻ͚Δͱࢥ͏
   ͭ·Γ೔ຊޠྗ͕ʢলུ͞Ε·ͨ͠ʣ
   ࢓ࣄͰͷϛχϚϜ͸+BWB
   ࠷৽ͱൺ΂Δͱະຬɻ
   

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7. ࢲʹͱͬͯͷ+BWB
   ԿΛ͢Δʹͯ͠΋ʮ࠷଎Ͱ࣮֬ʹ
   ࣮૷Ͱ͖Δ΋ͷʯ͸+BWB
   ଞͷݴޠ΋ͦΕͳΓʹ΍ͬͯΔ͚Ͳ
   ͳͷͰࢥߟ΋+BWBʹدͬͯΔ
   ࢥߟ͸ݴޠͷ੍໿Λड͚Δ͔Β࢓ํͳ͍
   

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8. ࠷ॳͷݴޠͷ঺հ
   Ұͭͷݴޠʹʮਫ਼௨ʯ͠·
   ͠ΐ͏ɻŧŔŕŪũƄŝſɻ
   ʮ+BWBŧŔŕŪũƄŝſʁʯͱฉ͔ΕΔͱ
   ࢲ΋एׯ᪳᪯͍͸͋Δ͚Ͳ
   ͲͷݴޠͰ͋Δ͔͸ॏཁͰ͸
   ͋Γ·ͤΜ
   ͕ɺͦͷݴޠͱ௕͘෇͖߹͏ͭ΋
   ΓͰ޲͖߹͍·͠ΐ͏
   

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9. +7.ͱ+BWB
   

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10. +7.
    +-BOH'FTU,BOTBJͱ͍͏͜ͱ
    Ͱɺ+7.Λ஌Βͳ͍ਓ͸ډͳ͍ͱ
    ࢥ͍·͢
    ʮ஌ͬͯΔʯͷ౓߹͍΋·ͪ·ͪ
    Ͱ͠ΐ͏͚Ͳ
    KZVLVUZPͷ࿩ͷ൓ԠͬͯͲ͏ͳΜͩΖ
    

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11. +7.ͱ+BWB
    +BWBͷେ͖ͳޭ੷ͷҰͭ͸+7.
    Λҭ͖ͯͯͨ͜ͱ
    গ͠લ͔Βଞͷ+7.ݴޠ͕+7.Λҭͯ
    ͯɺͦΕΛ+BWB͕࢖͏ͬͯ޲͖΋Ͱ͖
    ͖͚ͯͨͲɻ
    

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12. +BWBͷཱͪҐஔ
    +7.͕࣮ߦ͢ΔόΠφϦΛ࠷΋ૉ௚
    ʹදݱͰ͖Δݴޠ
    Ұ෦ͷߏจҎ֎͸KBWBQͨ͠ΒͲ͏ͳΔ͔
    ͸૝૾ͭ͘ɻଞݴޠΑΓ΋ڑ཭͕͍ۙɻ
    ͳͷͰίʔυͷՄࢹԽ͸
    $MBTTΛର৅ʹͯ͠Δˠ
    ଞݴޠͰ΋࢖͑Δ͚Ͳɺ༧ଌͰ͖ͳ͍ϊΠζ͕ʜʜ
    IUUQTHJUIVCDPNEEEKBWBKJH
    

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13. +BWB͸৑௕͔
    

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14. ৑௕
    ͍ΖΜͳจ຺Ͱʮ+BWB͸৑௕ʯ
    ͱݴΘΕ·͢ɻ
    ͚Ͳ࣮ମ͸͋·ΓΈ͑·ͤΜɻ
    จ຺͕·ͪ·ͪա͗ͯΧΦε
    ʮ৑௕ʯͬͯͳΜͩΖ͏ͬͯɻ
    

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15. ৑௕ͩͱ·͍ͣ͜ͱ
    ॻ͖ͮΒ͍
    ಡΈͮΒ͍
    

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16. ৑௕ͳͷͰॻ͖ͮΒ͍
    ৑௕͔ͩΒॻ͘ͷʹ͕͔͔࣌ؒ
    Δͷ͸େ໰୊
    Ͱ΋ଟ෼ͦΕɺ+BWBͷ͍ͤ͡Ό
    ͳ͍ͱࢥ͏ΜͰ͢
    

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17. ৑௕ͳͷͰॻ͖ͮΒ͍
    ΄ͱΜͲ
    શ෦͡Όͳ͍
    
    ͸*%&͕ղܾࡁΈ
    ࠓ࣌*%&Λ࢖Θͳ͍ͷ͸ߟ͑ͮΒ͍
    ·͔͞શจࣈλΠϐϯάͳΜͯ͠
    ͯ·ͤΜΑͶʁ
    ͜Ε͸ۃ୺͚ͩͲʮ·͔͞˓˓·ͤΜ
    ΑͶʁʯ͸͍͘ΒͰ΋͋Δ
    

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18. ·͔͞˓˓·ͤΜΑͶʁ
    ·͔͞JNQPSUจΛखͰॻ͍ͯ·ͤΜΑͶʁ
    ·͔͞GPSจΛશ෦ॻ͍ͯ·ͤΜΑͶʁ
    ·͔͞JGจΛશ෦ॻ͍ͯ·ͤΜΑͶʁ
    ·͔͞ϑΟʔϧυΛ࡞ͬͯίϯετϥΫλ
    Ͱ୅ೖͱ͔શ෦ॻ͍ͯ·ͤΜΑͶʁ
    Ұྫʹ͗͢ͳ͍ɻ
    

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19. ৑௕ͩͱ·͍ͣ͜ͱ
    ॻ͖ͮΒ͍
    ಡΈͮΒ͍
    ৑௕จ຺Ͱ͜ΕΛڍ͛Δͷ͸
    ʮࢲ͸*%&Λ࢖͍ͬͯ·ͤΜʯʹ͍ۙ
    

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20. ৑௕ͳͷͰಡΈͮΒ͍
    ͕ͬͪ͜࿦ͣΔՁ஋ͷ͋Δ࿩
    ʮ+BWB͸৑௕ʯͱݴ͏ͳΒ͜͜
    ͔Β߈ΊΑ͏
    ߈ΊͯͲ͏͢Δ
    

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21. ಡΈʹӨڹ͢Δ৑௕
    ಡΜͰ΋৘ใྔ͕૿͑ͳ͍
    ৘ใ͕૿͑ΔͳΒ৑௕ͱݴ͑ͳ͍
    ΑΓ؆ܿͳදݱ͕͋Δ
    ಉ͡৘ใྔͰͦΕͳΒ৑௕ͱݴ͑Δ
    ݴޠʗඪ४ϥΠϒϥϦͷදݱྗ͕ऑ͍
    

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22. େࣄͳͷ͸Մಡੑ
    ৑௕͸ՄಡੑΛଛͶΔ͔Β໰୊
    ʮಡΈʹ͍͘ʯͷҰҼʹͳΓ͑Δ
    Մಡੑ্͕͕Δ৑௕͸໰୊ͳ͍
    ʢ͋ΓಘΔ͔͸ผͱͯ͠ʣ
    

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23. ݴޠͷදݱྗʹ͍ͭͯ
    ࠓճ͸ѻ͍·ͤΜ
    ෼ͰೖΒͳ͍ʜʜ
    ݴޠ΍ඪ४ϥΠϒϥϦͷڧྗ͞͸
    ઃܭͷ੿͞Λ෴͍Ӆ͢͜ͱ͋Γ·
    ͢ɻରশੑΛଛͶͯΔͷʹؾ͚ͮ
    ͳ͍ͱ͔ɻ
    

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24. ίʔυ͸ಡΈ෺Ͱ͢
    鱺鱩鱋鱳+BWB鲫鱅鲿鲛鳫鲨++6($$$4QSJOH
    IUUQTTQFBLFSEFDLDPNJSPGIVUVVGBMTFKBWBLPEFJOHVOVNCFSDDDF
    鲫鱅鳁鲗鱮鲃鲘鱯鱐鱰%FW-07&ؔ੢DPNNJUNFOU
    IUUQTTQFBLFSEFDLDPNJSPGLPEPXPEPNBOOBLBOJ
    

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25. ৑௕ͳ+BWBίʔυ
    

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26. ϘΠϥʔϓϨʔτίʔυ
    ग़య͸8JLJQFEJBʢ͖Γͬ
    ʮݴޠ࢓্༷লུෆೳʯ
    ͑ɺHFUUFSTFUUFSͬͯผʹݴޠ࢓༷Ͱ͸ͳͯͩ͘ͳʜʜ
    ·͊ଟ͘ͷϥΠϒϥϦ͕ཁٻ͢Δ΋ͷͰ͸͋ΔͷͰ࣮࣭తʹ
    ͸ͬͯײ͡ͷ΋ؚΊΕ͹͍͍ΜͩΖ͏͚Ͳɻ
    

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27. ଟ͘ͷʮϘΠϥʔϓϨʔτίʔ
    υʯͱݴΘΕΔ΋ͷ͸ʮͦ͏ݴ
    ͏࢖͍ํͨ͠ΒཁΔΑͳ͊ʯͬ
    ͯͷ͕ਖ਼௚ͳͱͩͬͨ͜Γ͢Δ
    ʢͨͩͷײ૝
    

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28. ݴޠ࢓্༷ͷվળྫ
    USZXJUISFTPVSDFT
    μΠΞϞϯυΦϖϨʔλʔ
    WBS
    鱘鲑鲎鱴৑௕鱳ղফ鱯鱳鱐ʁ
    

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29. USZXJUISFTPVSDFT
    ΛѪͰΔ
    Ѫ鱬鲐ʹஸೡ鱰ݟ鲐鱔鲎鱉鱳ײ鱝鱬࢖鱨鱫鲃鱞
    

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30. USZXJUISFTPVSDFT
    ϦιʔεͷࣗಈDMPTFͱͯ͠ೝࣝ͞Ε
    Δ΋ͷ
    ଞݴޠ࢖ͬͯͯʮཉ͍͠ͳʔʯͱ
    ࢥͬͯͨච಄
    ͪͳΈʹ௥Ճ͞Εͨͷ͸େੲ
    ʢόʔδϣϯ൪߸͕൒෼ҎԼʣ
    

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32. ৑௕͔ͷ൑ఆ
    ίʔυ্͸৘ใྔ͕ݮ͍ͬͯΔ
    DMPTF͕ݺ͹ΕΔ͜ͱ΍ͦͷ৚݅
    ಡΈऔΔͷʹ஌͕ࣝ૿͍͑ͯΔ
    ஌͕ࣝ͋Ε͹ಡΈऔΔ଎౓͸্͕Δ
    Մಡੑ͸஌ࣝͱηοτ
    

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33. ৑௕͞͸վળ͞Ε͔ͨ
    :&4
    ࣗ෼Ͱ࣮૷͢Δʹ͸͔ͬͨΔͯ͘
    खΛൈ͍ͯͨͱ͜Ζͱ͔͕͖ͬͪ
    ΓରԠ͞ΕΔΑ͏ʹͳͬͯΔɻ
    TVQQSFTT͕ྫ֎Ͱѻ͑ͯɺෳ਺Ϧιʔε
    ѻ͏࣌ʹ͍͍ײ͡ʹͯ͘͠ΕͯɺӠʑɻ
    

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34. ʮ͔ͬͨΔ͍ʯͷ࿩
    ෳ਺ͷϦιʔεͷղ์Λਖ਼࣮͘͠૷
    ͢Δͷ͸ࠔ೉ͩ͠ɺ௨ৗ͸ෆཁͳ࣮૷
    Ͱ͋Δɻ
    ڵຯ͋Ε͹
    ϒϩάݟͯˠ
    

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35. ৑௕Ͱͳ͘ͳ͔ͬͨ
    ΞϓϦέʔγϣϯϨϕϧͩͱʮUSZʯͬͯͳ
    ΜͩΑײ͸͋Δ
    ʮྫ֎ॲཧʯͱݴ͏৘ใ͸৑௕ͳΜͩΑͶ͐ʜʜ
    ͔֬ʹྫ֎ॲཧͱηοτͳ͜ͱଟ͍Μ͚ͩͲɺผ
    ʹྫ֎ॲཧͨ͘͠ͳͯ͘DMPTF͚͍ͩͨ͠ͷʹ
    USZͬͯͳΜ΍ͶΜͬͯʜʜ
    

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36. ଞݴޠΛݟͯΈΔ
    ʢ׬શʹΠίʔϧ͡Όͳ͍͚Ͳʣ
    +BWB͚ͩྫ֎ॲཧʹࠞͬͯ͟Δɻ
    ʮྫ֎ॲཧͰDMPTF͞ΕΔͱ͔෼͔Δ͔ʂʯ͸؁Μͯ͡ड͚Δɻ
    Ͱ΋ൺֱͯ͠ʮ৑௕ʯͱ͸ݴ͍ͮΒ͍ɻ
    ݴޠ هड़
    +BWB USZ 999
    
    4DBMB 6TJOH 999
    
    ,PUMJO 999VTF
    (SPPWZ 999XJUI$MPTFBCMF
    $ VTJOH 999
    
    

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37. μΠΞϞϯυΦϖϨʔλʔ
    ΛѪͰΔ
    

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38. ͜Ε΋ଠݹͷߋ৽
    ໌֬ͳ৑௕ͷղফ
    ৘ใྔҰ੾ݮΒͣಡΈ΍͘͢ͳͬͨ
    

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39. WBS
    ΛѪͰΔ
    

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40. ࠷ۙೖͬͨ
    ࠷ۙʹόʔδϣϯ͕࠷৽ΑΓେ͖͍
    ͱ͍ͬͯ΋΋͏೥΋ܦͬͯΔ
    ଞݴޠͩͱ͘͝౰ͨΓલʹ͋ͬͨ΍ͭ
    

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41. ͜Ε͸৑௕ͷղফ͔ʁ
    ʮ4PNF5ZQF͕ͭ͋Δ͔Β
    ৑௕ʯ͸ͪΐͬͱҧ͏ɻ
    

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42. ίʔυ͸ࠨ͔ΒಡΉ
    ࠨ୺͸ίʔυͷҰ౳஍
    ͔ͩΒࠨʹॏཁͳ͜ͱΛॻ͖͍ͨ
    ࠷ॏཁͳͷ͸ܕͷ͸ͣʜʜ
    
    

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43. Ή͠Ζʮม਺Ͱ͋ΔʯͳΜͯ໌
    Β͔ͳ͜ͱΛΘ͟Θ͟ॻ͍ͯɺ
    ৑௕͕͞૿͑ͯͨΓɻ
    

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44. WBS͕ղফͨ͠΋ͷ
    ॻ͘ͷ͸ָʹͳͬͯΔ
    ͚Ͳ·͔͞ม਺ͷܕͱ͔खͰॻ
    ͍ͯ·ͤΜΑͶʁ
    ͋ɺKTIFMMͰ͸ศརɻ
    

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45. ࢲ͕ࠓճ࿩͔ͨͬ͠
    ͨ͜ͱ
    

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46. Մಡੑ͕ॏཁ
    ʮ৑௕͞ʯ͸ՄಡੑʹӨڹΛ༩͑ΔҰ
    Ҽʹա͗ͳ͍
    ৑௕Ͱ΋Մಡੑ্͕͕ΔͳΒ܁Γฦ͠
    ॻ͍ͯ΋͍͍
    هड़ੑ͸ͳΜͱ͔ͳΔɻอकੑʢมߋ࿙Ε
    ͷϦεΫͱ͔ʣ΋ͳΜͱ͔ͳΔɻʮͳΜͱ
    ͔ͳΔʯΛ;ͭ͏ʹ͍ͨ͠ɻ
    

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47. ܕΛॏࢹ͍ͨ͠
    ʮม਺Ͱ͋ΔʯʮϝιουͰ͋Δʯʹίʔ
    υͷҰ౳஍ͨΔࠨ୺ΛৡΓͨ͘ͳ͍
    ͔ͩΒWBSͱ͔GVOͱ͔EFGͱ͔ʹࠨ୺Λ͋͛ͨ
    ͘ͳ͍
    ͱݴ͍ͭͭम০ࢠʹୣΘΕΔ൵͠Έ
    म০ࢠͳ͠Ͱશ෦΍Γ͍ͨ
    ৚݅੔͑ͯ֎ͨ͠Γ͢Δˠ
    

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48. ݴޠͷ৑௕ΛޠΔͳΒ
    ͦͷʮ৑௕ʯ͕Կͳͷ͔ɺ΋͏গ͠ߟ͑ͯ
    ΈΔͱؾ͖͕ͮ͋Δ͔΋͠Εͳ͍ɻ
    ෳ਺ͷݴޠʹڵຯΛ࣋ͬͨͷͳΒɺͦΕͧ
    ΕͷΞϓϩʔνΛݟൺ΂ͯɺղܾͷํ޲ͷ
    ଍͠ʹ͠Α͏ɻ
    ଟ͘ͷʮ৑௕ʯ͸ݴޠ͡Όͳ͘ɺઃܭͷෆ
    ٢ͳʹ͓͍Ͱ͢ɻ޲͖߹͍·͠ΐ͏ɻ
    

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49. ޷͖ͳݴޠ͸μϝͩ͠
    ͯ͠ͳΜ΅ͩͱࢥ͏
    ݴޠEJTฉ鱉鱫鲇ʮ؁鱉鱯鱅EJT鲐鱯鲎鱘鱘鱥
    鲒鱅ʯ鲄鱤鱉鱰ࢥ鱍鲐鱭৺Ժ鲉鱐鱰鱯鲑鲐
    

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