渋谷Java ＃３

guava totallylazy java8
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1. Java8ɺͪΐͬͱͦͷલʹ ौ୩Java #3 Urakawa Tomohiro / @mystelynx 13೥9݄28೔౔༵೔
2. ࣗݾ঺հ Urakawa Tomohiro @mystelynx ؋ୂ࢘ྩ෦Level.19 ΫοΩʔ԰͞Μ͸ଔۀ͠·ͨ͠ɻ גࣜձࣾALBERTɹγεςϜ։ൃ෦ ࠷ۙ͸RedshiftͱٔΕ͍ͯ·͢ɻ 13೥9݄28೔౔༵೔
3. Agenda JavaͰ࢖͑Δؔ਺ܕϥΠϒϥϦ guava-libraries totallylazy ͦΕͧΕͷ࢖༻্ͷ஫ҙɾ༻๏ʗ༻ྔͳͲ Java8ͱซ༻͢Δͱʁ 13೥9݄28೔౔༵೔
4. 13೥9݄28೔౔༵೔
5. guava-libraries https:/ /code.google.com/p/guava-libraries/ ࠷৽όʔδϣϯɿ15.0 (2013/09/06) υΩϡϝϯτ͕݁ߏࡉ͔͘ॻ͔Ε͍ͯΔ ศརͳCollection΍UtilitiesͳͲ΋ؚΜͰ͍Δ ࠓճ͸ؔ਺ܕϓϩάϥϛϯάػೳʹ஫໨ 13೥9݄28೔౔༵೔
6. ίʔυྫ̍ ݁ߏ௕ͬͨΒ͍͠ʢओ؍ 13೥9݄28೔౔༵೔
7. ίʔυྫ̎ ͦ͜͸͔ͱͳ͘υϠײΛײ͡Δʢओ؍ 13೥9݄28೔౔༵೔
8. ॴײ CharMatcherͳͲᙱ͍ͱ͜Ζʹख͕ಧ͘ ແବʹ࣮૷͠ͳ͍ͨΊʹ΋ɺԿ͕༻ҙ͞Ε ͯΔ͔͸େମ೺Ѳ͓ͯ͜͠͏ શମతʹΫϥεʗϝιου໊ΛۃྗΘ͔Γ΍ ͘͢͠Α͏ͱͯ͘͠Ε͍ͯΔײ͕͋Δɻ ٯʹ෼͔Γʹ͍͘ʁʢmapͩΖ…ͱ͔ʣ 13೥9݄28೔౔༵೔
9. ஫ҙ Java8ͷඪ४ϥΠϒϥϦͱΫϥε໊͕ඃΔ java.util.function.Function vs com.google.common.base.Function java.util.function.Predicate vs com.google.common.base.Predicate ඍົʹϝιου໊͕׳Εͳ͍ 13೥9݄28೔౔༵೔
10. 13೥9݄28೔౔༵೔
11. totallylazy https:/ /code.google.com/p/totallylazy/ ࠷৽όʔδϣϯɿ1113 (2013/08/25) υΩϡϝϯτແ͍ʢʀ∀ʀʣ ιʔεʂˠJavaDoc΋ແ͍ʢʀ∀ʀʣɹɹɹ ςετˠ໢ཏ͞Εͯͳ͍ʢʀ∀ʀʣ 13೥9݄28೔౔༵೔
12. ઃܭࢥ૝తʹ ClojureͷCollectionͷ༷ʹՄೳͳݶΓ஗ԆධՁ MLܥݴޠͷؔ਺໊ʗϝιου໊Λ౿ऻ Haskell΍Scalaܦݧऀ͸ೃછΈ΍͍͔͢΋ HamcrestͷMatcherΛPredicateʹ࢖͑Δ static importଟ༻ 13೥9݄28೔౔༵೔
13. ίʔυྫ̍ େے͸guavaͱมΘΒͳ͍ɻ mapͱ͔filterͱ͔͸static import͞Εͯ·͢ 13೥9݄28೔౔༵೔
14. ίʔυྫ̎ υϠ ιʔεΛݟͳ͕ΒؤுΔ͔͠ͳ͍ؾ͕͢Δ sequence(foo)͕ɺJava8ͷStreamͷΠϝʔδ 13೥9݄28೔౔༵೔
15. ॴײ ͱʹ͔͘υΩϡϝϯτ͕ແ͍ ઓಆྗͷ͕ܹ͍ࠩ͠ هड़͸ͱʹ͔͘؆ܿɻJava8ͷϥϜμࣜͰॻ͘ ΑΓ؆ܿɻ 13೥9݄28೔౔༵೔
16. ஫ҙ Java8ͷඪ४ϥΠϒϥϦͱΫϥε໊͕ඃΔ com.googlecode.totallylazy.Predicate ௚઀newͰΠϯελϯεੜ੒͢ΔͷͰ͸ͳ ͘ɺSequences, PredicatesͳͲͳͲ͔Β static importͯ͠࢖͏ͷ͕ఆੴ eclipseͩͱ͠ΜͲ͍Πϝʔδʢओ؍ 13೥9݄28೔౔༵೔
17. 13೥9݄28೔౔༵೔
18. Java8 https:/ /jdk8.java.net/download.html ࠷৽όʔδϣϯɿ8 build b108 2014/03ϦϦʔε༧ఆʂ ؔ਺ܕػೳͷଞʹ΋DateTimeͱ͔ɺσϑΥϧ τϝιουͱ͔ 13೥9݄28೔౔༵೔
19. ίʔυྫ̍ ͜ͷॻ͖ํ͢ΔͱͲΕ΋มΘΒͳ͍Ͱ͢Ͷ 13೥9݄28೔౔༵೔
20. ίʔυྫ̎ ͜Ε͕Ұ൪୹͍ؾ͕͢Δ stream()ͯ͠ɺ࠷ޙʹList΁໭͢ ϥϜμࣜ࢖͏ͱnew new͠ͳ͍͍ͯ͘ͷͰݟ ΍͍͢ 13೥9݄28೔౔༵೔
21. ͍ͭͰʹ guava/totallylazyͦΕͧΕϥϜμࣜͰ guava͸؆ܿʹͳͬͯGood totallylazy͸৑௕ʹͳͬͯBad 13೥9݄28೔౔༵೔
22. ·ͱΊ Ϋϥε໊͕ඃͬͯ͘ΔͷͰɺ஫ҙ͠Α͏ totallylazy࢖͑Δͱ௒γϯϓϧ ˞ʮ࢖͑Δͱʯ guava͸ίϨΫγϣϯ΍ϢʔςΟϦςΟͳͲ͸ ໰୊ͳ͘࢖͑Δ 13೥9݄28೔౔༵೔
23. ͓ΘΓ 13೥9݄28೔౔༵೔