Upgrade to Pro
— share decks privately, control downloads, hide ads and more …
Speaker Deck
Features
Speaker Deck
PRO
Sign in
Sign up for free
Search
Search
Java Wars VIII: The Function Awakens
Search
Grzegorz Piwowarek
April 11, 2016
Programming
0
650
Java Wars VIII: The Function Awakens
Grzegorz Piwowarek
April 11, 2016
Tweet
Share
More Decks by Grzegorz Piwowarek
See All by Grzegorz Piwowarek
Javaslang DevoxxBE 2016
pivovarit
1
120
Javaslang DevoxxMA
pivovarit
2
760
JavaSlang JavaDayKiev 2016
pivovarit
0
66
Javaslang - functional Java done right
pivovarit
0
210
Java 8 vs. Checked Exceptions
pivovarit
0
100
Java 8: Lambdas, Monads and Java Collections
pivovarit
1
94
Other Decks in Programming
See All in Programming
pixivアプリでマルチモジュールを実現するまで
gatosyocora
1
130
1인 개발자로 행복하게 살기 - GDG 송도 헬로월드 2024
benjaminkim
1
5.6k
OpenAPIを中心に考えるAPI開発入門 / Introduction to API Development with a Focus on OpenAPI
seike460
PRO
2
120
Micro Frontends for Java Microservices - Devnexus 2024
mraible
PRO
0
430
try! Swift Tokyo 2024のLT枠に採択されたプロポーザルを出すときに考えていたこと
ski
0
340
スクラムチームと認知負荷 - ニフティのスクラムトーク Vol2. / NIFTY Tech Talk #18
niftycorp
PRO
1
120
0→1と1→10の狭間で Javaという技術選定を振り返る/Reflecting on the Decision to Choose Java Between Scaling from 0 to 1 and 1 to 10
jaguar_imo
2
370
try! Swift Tokyo 2024 参加報告 / try! Swift Tokyo 2024 Report
hironytic
0
170
AWS Application Composerで始める、 サーバーレスなデータ基盤構築 / 20240406-jawsug-hokuriku-shinkansen
kasacchiful
1
250
ONE WEDGE_company_guide
1wedge_one
0
380
はてなにおける CSS Modules、及び CSS Modules に足りないもの / CSS Modules in Hatena, and CSS Modules missing parts
mizdra
3
360
SpringBoot+MyBatisで例外が出たときどこを見るか
syukai
0
110
Featured
See All Featured
A Philosophy of Restraint
colly
196
16k
We Have a Design System, Now What?
morganepeng
42
6.7k
Into the Great Unknown - MozCon
thekraken
10
980
Visualization
eitanlees
135
14k
Rebuilding a faster, lazier Slack
samanthasiow
72
8.2k
CSS Pre-Processors: Stylus, Less & Sass
bermonpainter
352
28k
For a Future-Friendly Web
brad_frost
171
8.9k
Responsive Adventures: Dirty Tricks From The Dark Corners of Front-End
smashingmag
243
20k
Practical Orchestrator
shlominoach
181
9.7k
Embracing the Ebb and Flow
colly
79
4.1k
Imperfection Machines: The Place of Print at Facebook
scottboms
258
12k
RailsConf 2023
tenderlove
2
530
Transcript
Grzegorz Piwowarek
[email protected]
GitHub, Twitter :: @pivovarit
GitHub, Twitter :: @pivovarit VISIONS OF TONDAL.PL
None
None
None
None
Why?
//TODO: -lambda expressions -java.util.function -monad -java.util.Optional -java.util.stream.Stream GitHub, Twitter ::
@pivovarit
lambda expressions GitHub, Twitter :: @pivovarit
lambda expressions (...) -> statement - Anonymous function GitHub, Twitter
:: @pivovarit
lambda expressions x -> x + 1 GitHub, Twitter ::
@pivovarit
lambda expressions x -> x + 1 GitHub, Twitter ::
@pivovarit () -> 42
lambda expressions x -> x + 1 GitHub, Twitter ::
@pivovarit () -> 42 () -> {return 42;}
lambda expressions x -> x + 1 GitHub, Twitter ::
@pivovarit () -> 42 (x, y) -> {} () -> {return 42;}
lambda expressions x -> x + 1 - No type
information GitHub, Twitter :: @pivovarit
method references GitHub, Twitter :: @pivovarit
java.util.function GitHub, Twitter :: @pivovarit
Function<T, R>, BiFunction<T,U,R> Consumer<T> extends Function<T,Void> Supplier<T> extends Function<Void, T>
Predicate<T> extends Function<T, Boolean> UnaryOperator<T> extends Function<T, T> BinaryOperator<T> extends BiFunction<T,T,T> GitHub, Twitter :: @pivovarit
Function<T, R>, BiFunction<T,U,R> Consumer<T> extends Function<T,Void> Supplier<T> extends Function<Void, T>
Predicate<T> extends Function<T, Boolean> UnaryOperator<T> extends Function<T, T> BinaryOperator<T> extends BiFunction<T,T,T> GitHub, Twitter :: @pivovarit
Function<T, R>, BiFunction<T,U,R> Consumer<T> extends Function<T,Void> Supplier<T> extends Function<Void, T>
Predicate<T> extends Function<T, Boolean> UnaryOperator<T> extends Function<T, T> BinaryOperator<T> extends BiFunction<T,T,T> GitHub, Twitter :: @pivovarit
Function<T, R>, BiFunction<T,U,R> Consumer<T> extends Function<T,Void> Supplier<T> extends Function<Void, T>
Predicate<T> extends Function<T, Boolean> UnaryOperator<T> extends Function<T, T> BinaryOperator<T> extends BiFunction<T,T,T> GitHub, Twitter :: @pivovarit
Function<T, R>, BiFunction<T,U,R> Consumer<T> extends Function<T,Void> Supplier<T> extends Function<Void, T>
Predicate<T> extends Function<T, Boolean> UnaryOperator<T> extends Function<T, T> BinaryOperator<T> extends BiFunction<T,T,T> GitHub, Twitter :: @pivovarit
MONAD GitHub, Twitter :: @pivovarit
GitHub, Twitter :: @pivovarit
GOOGLE IMAGES...
GOOGLE IMAGES...
GOOGLE IMAGES...
GOOGLE IMAGES...
GOOGLE IMAGES...
GOOGLE IMAGES...
GOOGLE IMAGES...
GOOGLE IMAGES...
... GitHub, Twitter :: @pivovarit
MONAD Design pattern http://got-steam.com/ GitHub, Twitter :: @pivovarit
Why bother? : Boilerplate-- Readability++ Complexity-- GitHub, Twitter :: @pivovarit
Imperative approach GitHub, Twitter :: @pivovarit
Declarative approach GitHub, Twitter :: @pivovarit
Generic type: "unit" method: "bind" method: MONAD GitHub, Twitter ::
@pivovarit
Generic type: "unit" method: "bind" method: MONAD GitHub, Twitter ::
@pivovarit
Generic type: "unit" method: "bind" method: MONAD GitHub, Twitter ::
@pivovarit
Generic type: "unit" method: "bind" method: MONAD GitHub, Twitter ::
@pivovarit
GitHub, Twitter :: @pivovarit
GitHub, Twitter :: @pivovarit
GitHub, Twitter :: @pivovarit
http://www.ivanaborovnjak.com/project/box-in-a-box/ GitHub, Twitter :: @pivovarit
Solution GitHub, Twitter :: @pivovarit
Monads in Java 8 Optional Stream CompletableFuture GitHub, Twitter ::
@pivovarit
Monads in Java 8 Optional Stream CompletableFuture GitHub, Twitter ::
@pivovarit
Optional Encapsulation of operations on optional values GitHub, Twitter ::
@pivovarit
Optional Encapsulation of operations on optional values GitHub, Twitter ::
@pivovarit
Optional type: "unit": "bind": GitHub, Twitter :: @pivovarit
Optional type: Optional<T> "unit": "bind": GitHub, Twitter :: @pivovarit
Optional type: Optional<T> "unit": Optional.ofNullable(), Optional.of() "bind": GitHub, Twitter ::
@pivovarit
Optional type: Optional<T> "unit": Optional.ofNullable(), Optional.of() "bind": Optional.flatMap(), Optional.map() GitHub,
Twitter :: @pivovarit
Filtering an Optional .filter(Predicate<T>) GitHub, Twitter :: @pivovarit
Unwrapping an Optional .get() .orElse(T default) .orElseGet(Supplier<T>) .orElseThrow(Supplier<Ex>) .ifPresent(Consumer<T>) GitHub,
Twitter :: @pivovarit
GitHub, Twitter :: @pivovarit http://theworryfreelife.com/wp-content/uploads/2015/08/comfort-zone.jpg
Java 7 style GitHub, Twitter :: @pivovarit
Java 8 style GitHub, Twitter :: @pivovarit
Java 7,5 style ;) GitHub, Twitter :: @pivovarit
Java 7,5 style ;) GitHub, Twitter :: @pivovarit
GitHub, Twitter :: @pivovarit
GitHub, Twitter :: @pivovarit
Stream Encapsulation of operations on multiple items GitHub, Twitter ::
@pivovarit
Stream type: Stream<T> "unit": Stream.of(), Arrays.stream(), Collection.stream() "bind": Stream.flatMap() GitHub,
Twitter :: @pivovarit
Stream GitHub, Twitter :: @pivovarit
Stream GitHub, Twitter :: @pivovarit
Stream GitHub, Twitter :: @pivovarit
Imperative vs. Declarative GitHub, Twitter :: @pivovarit
Imperative vs. Declarative GitHub, Twitter :: @pivovarit
Stream && Optional GitHub, Twitter :: @pivovarit
Stream lazy-initialized nonreusable GitHub, Twitter :: @pivovarit
intermediate operations .map() .flatMap() .filter() .peek() GitHub, Twitter :: @pivovarit
intermediate operations .map() .flatMap() .filter() .peek() Stream not consumed: does
not print anything GitHub, Twitter :: @pivovarit
Consuming Stream .forEach(Consumer<T>) .collect() .reduce(BinaryOperator<T>) .allMatch(), anyMatch(), noneMatch() .findFirst(), findAny()
.count() .toArray() GitHub, Twitter :: @pivovarit
Stream.reduce() GitHub, Twitter :: @pivovarit
Collectors .toList(), toMap(), toSet(), toCollection() .minBy(), maxBy() .joining() .partitioningBy() ...and
many others GitHub, Twitter :: @pivovarit
Collectors.toList() GitHub, Twitter :: @pivovarit
Stream in APIs "any string".chars() Files.newDirectoryStream() Random.ints() ... GitHub, Twitter
:: @pivovarit
you want more? GitHub, Twitter :: @pivovarit
github.com/ TouK/ThrowingFunction http://www.javaslang.io/ GitHub, Twitter :: @pivovarit
Thank You! GitHub, Twitter :: @pivovarit
REFERENCES: -"MONADIC JAVA" BY MARIO FUSCO -"WHAT'S WRONG WITH JAVA
8" BY PIERRE-YVES SAUMONT -WWW.ORACLE.COM -"A FISTFUL OF MONADS" - LEARN YOU A HASKELL FOR GREAT GOOD