[B! java8][stream] snjxã®ãƒ–ãƒƒã‚¯ãƒžãƒ¼ã‚¯

snjx id:snjx

java8ã¨streamã«é–¢ã™ã‚‹snjxã®ãƒ–ãƒƒã‚¯ãƒžãƒ¼ã‚¯ (11)

${{author_name}}$

{{{comment_expanded}}}

{{label}}

{{#is_bookmark}}ãƒªã‚¹ãƒˆ{{/is_bookmark}}{{^is_bookmark}}ãƒªãƒ³ã‚¯{{/is_bookmark}}

${{author_name}}$
{{author_name}}{{created}}
{{ #comment }}{{ comment }}{{ /comment }}
- {{ label }}

${{author_name}}$

{{{comment_expanded}}}

{{label}}

{{#is_bookmark}}ãƒªã‚¹ãƒˆ{{/is_bookmark}}{{^is_bookmark}}ãƒªãƒ³ã‚¯{{/is_bookmark}}

Stream APIã®å§‹ã‚æ–¹
ã“ã®è¨˜äº‹ã¯ã€Java Advent Calendar 2013ã®2æ—¥ç›®ã¨ã—ã¦æ›¸ã‹ã‚ŒãŸã‚‚ã®ã§ã™ã€‚ Java SE 8ã§ã¯ã€Stream APIã¨ã„ã†æ–°ã—ã„APIãŒå°Žå…¥ã•ã‚Œã¾ã™ã€‚Stream APIã¯ã€ä½•ã‚‰ã‹ã®è¦ç´ ã®é›†ã¾ã‚Šï¼ˆé…åˆ—ã‚„ã‚³ãƒ¬ã‚¯ã‚·ãƒ§ãƒ³ã€ã‚ã‚‹ã„ã¯ãƒ†ã‚ã‚¹ãƒˆãƒ•ã‚¡ã‚¤ãƒ«ã‚’èªã¿å–ã‚‹ã¨ãã®ä¸€è¡Œä¸€è¡Œãªã©ï¼‰ã«å¯¾ã™ã‚‹ã•ã¾ã–ã¾ãªæ“ä½œã‚’æŠ½è±¡åŒ–ã—ãŸã€ã¨ã¦ã‚‚ä¾¿åˆ©ãªAPIã§ã™ã€‚ Stream APIã¯ã€Java SE 8ã®æ–°æ©Ÿèƒ½ã¨ã—ã¦ã‚‚ç‰¹ã«æ³¨ç›®ã•ã‚Œã¦ã„ã‚‹ã‚‚ã®ã®1ã¤ã§ã—ã‚‡ã†ã€‚é¡žä¼¼ã®ä»•çµ„ã¿ãŒC#ã‚„Scalaã‚„Rubyãªã©ä»–ã®è¨€èªžã§ã‚‚åºƒãŒã£ã¦ãŠã‚Šã€Javaã«ã‚‚ã¤ã„ã«ã€ã¨å¾…ã¡æœ›ã‚“ã§ã„ã‚‹æ–¹ã‚‚å¤šã„ã§ã—ã‚‡ã†ã€‚ ã¨ã“ã‚ãŒã€Streamã‚¤ãƒ³ã‚¿ãƒ¼ãƒ•ã‚§ãƒ¼ã‚¹ãŒæŒã¤æ§˜ã€…ãªä¾¿åˆ©ãƒ¡ã‚½ãƒƒãƒ‰ï¼ˆfilterã€mapã€flatMapã€collectãªã©ï¼‰ã¯ã€ã‚ã¡ã“ã¡ã§ã‚ˆãç´¹ä»‹ã•ã‚Œã‚‹ä¸€æ–¹ã§ã€æ¬¡ã®2ç‚¹ã¯ã€ã‚ã¾ã‚Šæ³¨ç›®ã•ã‚Œã¦ã„ãªã„ã‚ˆã†ã«æ€ã„ã¾ã—ãŸï¼ˆã¼ããŒè¦‹ãŸé™
snjx 2017/09/06
Stream

API

Java

java8

ã‚·ã‚¹ãƒ†ãƒ é–‹ç™º

è³‡æ–™

è€ƒå¯Ÿ

æŠ€è¡“

ã‚ã¨ã§èªã‚€
ãƒªãƒ³ã‚¯
ã€åˆå¿ƒè€…å‘ã‘ã€‘Java8 Stream APIã«ã¤ã„ã¦çŸ¥ã‚ã† | Casley Deep Innovationsæ ªå¼ä¼šç¤¾ æŠ€è¡“ãƒ–ãƒã‚°
ãƒ—ãƒªãƒŸãƒ†ã‚£ãƒ–åž‹ã«ã¯ãã‚Œã«å¿œã˜ãŸStreamã‚¤ãƒ³ã‚¿ãƒ•ã‚§ãƒ¼ã‚¹ãŒç”¨æ„ã•ã‚Œã¦ã„ã¾ã™ã€‚ Javaã¯Stringã‚’ãƒ—ãƒªãƒŸãƒ†ã‚£ãƒ–åž‹ã§ã¯ãªã„ã¨ã—ã¦ã„ã‚‹ã®ã§StringStreamã¯ã‚ã‚Šã¾ã›ã‚“ã€‚ æ˜”ã¯Aã¨Bã®å‡¦ç†ã‚’åŒæ™‚ã«å®Ÿè¡Œã™ã‚‹ã«ã¯ï¼’å°ã®PCã«ãã‚Œãžã‚Œã®å‡¦ç†ã‚’æŒ¯ã‚Šåˆ†ã‘ã¦å®Ÿè¡Œã™ã‚‹ã“ã¨ã§ æ™‚é–“ã®çŸç¸®ã‚’ã—ã¦ã„ã¾ã—ãŸã€‚ã“ã‚Œã¯åˆ†æ•£å‡¦ç†ã¨è¨€ã‚ã‚Œã¦ã„ã¾ã™ã€‚ ã“ã‚Œã¯1ã¤ã®PCã«1ã¤ã®CPUã—ã‹ãªã‹ã£ãŸã‹ã‚‰ã§ã—ãŸã€‚ ã—ã‹ã—ã€ä»Šã¯1ã¤ã®PCã«è¤‡æ•°ã®CPUãŒã‚ã‚Šã€Aã¨Bã®å‡¦ç†ã‚’å®Ÿè¡Œã™ã‚‹äº‹ãŒå‡ºæ¥ã¾ã™ã€‚ ã“ã‚ŒãŒä¸¦åˆ—å‡¦ç†ã¨ã„ã†ã‚‚ã®ã§ã™ã€‚ ç¾åœ¨ã¯ä¸¦åˆ—ã¨åˆ†æ•£ã‚’çµ„ã¿åˆã‚ã›ãŸä¸¦åˆ—åˆ†æ•£å‡¦ç†ã¨ã„ã†å½¢ãŒåºƒãä½¿ã‚ã‚Œã¦ã„ã¾ã™ã€‚ ãã“ã§Java8ã«ã‚‚ä¸¦åˆ—å‡¦ç†ã‚’å¯èƒ½ã¨ã«ã™ã‚‹Stream APIãŒã¤ã„ã«è¿½åŠ ã•ã‚ŒãŸã®ã§ã—ã‚‡ã†ã€‚ StreamAPIã®ä½¿ã„æ–¹ã¯ä¸é–“æ“ä½œã¨çµ‚ç«¯æ“ä½œï¼ Stream APIã¯åŸºæœ¬çš„ã«ã€Žä¸é–“æ“ä½œã€ã€ã€Žçµ‚ç«¯æ“ä½œã€ã¨ã„ã†ä½¿ã„æ–¹ã«ãªã‚Šã¾ã™ã€‚ S
snjx 2017/09/06
Stream

Java

Java8

StreamAPI

ãƒ©ãƒ ãƒ€å¼

webã‚µãƒ¼ãƒ“ã‚¹

ã‚·ã‚¹ãƒ†ãƒ é–‹ç™º

æŠ€è¡“

è³‡æ–™

è€ƒå¯Ÿ
ãƒªãƒ³ã‚¯
Java 8 Stream API ã«ãƒ†ã‚ã‚¹ãƒˆã‚’æµã—ã¦ã¿ã¦ï¼ˆä¸é–“æ“ä½œç·¨ï¼‰ - Qiita
Java 8 Stream API ã«ãƒ†ã‚ã‚¹ãƒˆã‚’æµã—ã¦ã¿ã‚‹ï¼ˆç”Ÿæˆç·¨ï¼‰- Qiita Java 8 Stream API ã«ãƒ†ã‚ã‚¹ãƒˆã‚’æµã—ã¦ã¿ãŸï¼ˆçµ‚ç«¯æ“ä½œç·¨ï¼‰- Qiita Java 8 Stream API ã«ãƒ†ã‚ã‚¹ãƒˆã‚’æµã—ã¦ã¿ã¦ï¼ˆä¸é–“æ“ä½œç·¨ï¼‰â†ã€€ä»Šã‚³ã‚³ ä»Šã•ã‚‰ã§ã™ãŒã€æ˜”æ›¸ãã‹ã‘ãŸæŠ•ç¨¿ã®ãŠè”µå‡ºã—ã™ã‚‹ã“ã¨ã«ã—ã¾ã™ã€‚ ã¾ã é€”ä¸ã§ã™ãŒã€æ›¸ãæºœã‚ãŸã‚³ãƒ¼ãƒ‰ã‚’éšæ™‚è¿½è¨˜ã—ã¦ã„ãäºˆå®šã§ã™ã€‚ [2017-04-09] 3.4 sorted() ã‚’è¿½è¨˜ [2017-04-15] 3.5 map() è¿½è¨˜ [2017-04-23] 3.6 flatMap() è¿½è¨˜ ã‚¹ãƒˆãƒªãƒ¼ãƒ ã¨ãƒ‘ã‚¤ãƒ—ãƒ©ã‚¤ãƒ³ ã€Šçœç•¥ã€‹ Java é–¢æ•°ã‚¤ãƒ‡ã‚£ã‚ªãƒ ã€Šçœç•¥ã€‹ 3 ä¸é–“æ“ä½œ ã€Šçœç•¥ã€‹ peek(Consumer<? super T> action) skip(long maxSize) limit(long maxSize) filte
snjx 2017/09/05
java

java8

ã‚·ã‚¹ãƒ†ãƒ é–‹ç™º

è€ƒå¯Ÿ

æŠ€è¡“

è³‡æ–™

Stream
ãƒªãƒ³ã‚¯
Java 8 Stream API ã«ãƒ†ã‚ã‚¹ãƒˆã‚’æµã—ã¦ã¿ã‚‹ï¼ˆç”Ÿæˆç·¨ï¼‰ - Qiita
Java 8 Stream API ã«ãƒ†ã‚ã‚¹ãƒˆã‚’æµã—ã¦ã¿ã‚‹ï¼ˆç”Ÿæˆç·¨ï¼‰- Qiita Java 8 Stream API ã«ãƒ†ã‚ã‚¹ãƒˆã‚’æµã—ã¦ã¿ãŸï¼ˆçµ‚ç«¯æ“ä½œç·¨ï¼‰- Qiita Java 8 Stream API ã«ãƒ†ã‚ã‚¹ãƒˆã‚’æµã—ã¦ã¿ã¦ï¼ˆä¸é–“æ“ä½œç·¨ï¼‰- Qiita Java 8 ãŒå‡ºã¦ã‹ã‚‰ã ã„ã¶ãŸã¤ã‚ã‘ã ãŒ ãã®ç›®çŽ‰æ©Ÿèƒ½ã®ä¸€ã¤ã ã£ãŸ Stream API ã¯ä»Šã€é–‹ç™ºç¾å ´ã§ã©ã‚Œã ã‘ä½¿ã‚ã‚Œã¦ã„ã‚‹ã®ã ã‚ã†ã‹ã€‚è‡ªåˆ†ã‚‚å‡ºå§‹ã‚ãŸã“ã‚ã«ã¡ã‚‡ã£ã¨è§¦ã£ã¦ç†è§£ã—ãã‚Œãªã„ã¾ã¾æ•¬é ã—ã¦ããŸä¸€äººã ãŒã€æœ€è¿‘ã¾ãŸä½¿ã†æ©Ÿä¼šãŒã‚ã£ãŸã®ã§æƒ…å ±ãªã©æ¼ã£ã¦ã„ã‚‹ã€‚ ã—ã‹ã—ã¾ã å…¥é–€çš„ãªç´¹ä»‹ã‹ãƒ‡ã‚£ãƒ¼ãƒ—ãªæ¤œè¨¼ã°ã‹ã‚Šã§ã€ã©ã†ã‚‚ãƒ”ãƒ³ã¨æ¥ãªã„ã€‚ã‚‚ã— Stream ãŒä¾¿åˆ©ã§åºƒãé–‹ç™ºç¾å ´ã§ä½¿ã‚ã‚Œã¦ã„ã‚‹ãªã‚‰ã€ãã‚ãã‚ã‚‚ã†å°‘ã—å®Ÿè·µçš„ãªæƒ…å ±ãŒä¸ŠãŒã£ã¦ãã¦ã„ã„ã¨æ€ã†ã®ã ãŒã€‚ ç¾çŠ¶ã€Stream ã‚’ã¡ã‚ƒã‚“ã¨ã¯ç†è§£ã—ã‚ˆã†ã¨ã™ã‚‹ãªã‚‰ã€ã‚„ã¯ã‚Šè‡ªåˆ†ã®æ‰‹ã§å…·ä½“çš„ãªã‚³ãƒ¼ãƒ‰ã‚’
snjx 2017/09/05
java

java8

ã‚·ã‚¹ãƒ†ãƒ é–‹ç™º

è€ƒå¯Ÿ

æŠ€è¡“

è³‡æ–™

Stream
ãƒªãƒ³ã‚¯
Java8ã®Stream APIã®ä½¿ã„æ–¹ï¼ˆä¸é–“æ“ä½œç·¨â‘¡ - flatMap, distinct, limit, skipï¼‰ - TASK NOTES
Stream API ä¸é–“æ“ä½œã® flatMapã€distinctã€limitã€skip ã«ã¤ã„ã¦ä½¿ã„æ–¹ã‚’ã¾ã¨ã‚ã¾ã—ãŸã€‚ flatMapï¼šå¤‰æ› ( 1:N ) å¼•æ•°ï¼šFunction<T, Stream<R>> ï¼ æˆ»ã‚Šå€¤ï¼šStream<R> flatMapã¯mapãƒ¡ã‚½ãƒƒãƒ‰ã¨ä¼¼ã¦ã„ã¾ã™ãŒFunction<T, Stream<R>>ã‚’å¼•æ•°ã«å–ã‚Šã€è¦ç´ Tã‹ã‚‰Stream<R>ã‚’ç”Ÿæˆã—ã¾ã™ã€‚ä½•ã‚’è¨€ã£ã¦ã‚‹ã®ã‹ã¨ã„ã†ã¨mapãƒ¡ã‚½ãƒƒãƒ‰ã®å ´åˆã¯å…¥åŠ›ã¨å‡ºåŠ›ãŒ 1:1ã€Œ(T) -> Rã€ã«ãªã‚Šã¾ã™ãŒã€flatMapãƒ¡ã‚½ãƒƒãƒ‰ã®å ´åˆã¯ 1:Nã€Œ(T) -> Stream<R>ã€ã¨ãªã‚Šã€Rã‚’è¤‡æ•°è¿”ã—ã¾ã™ã€‚ï¼å€‹ã§ã‚‚å¤§ä¸ˆå¤«ã§ã™ã€‚ flatMapã®ä½¿ã„æ–¹ Integerã®Listã‚’å„æ•°å€¤ã®æ•°ã ã‘å‡ºåŠ›ã™ã‚‹ã‚µãƒ³ãƒ—ãƒ«ã§ã™ã€‚ List<Integer> list = Arrays.asList(1, 2, 3); // ãƒ©ãƒ ãƒ€
snjx 2017/09/05
java

java8

ã‚·ã‚¹ãƒ†ãƒ é–‹ç™º

è€ƒå¯Ÿ

æŠ€è¡“

è³‡æ–™

Stream
ãƒªãƒ³ã‚¯
ãƒ©ãƒ ãƒ€å¼ãƒ»Stream APIã®ç†è§£ã®ãƒã‚¤ãƒ³ãƒˆã¯ã€Œåž‹ã€ - è¡Œãã‚ãŸã‚Šã°ã£ãŸã‚Šã‚¨ãƒ³ã‚¸ãƒ‹ã‚¢ã®æ—¥è¨˜
ã¯ã˜ã‚ã« Java SE 8ãŒãƒªãƒªãƒ¼ã‚¹ã•ã‚Œã¦ã€ãã‚ãã‚1å¹´ãŒçµŒã¨ã†ã¨ã—ã¦ã„ã¾ã™ã€‚æ—©ã„ã‚‚ã®ã§ã™ã€‚ ãã‚Œã¯ã™ãªã‚ã¡ã€Java SE 7ã®ã‚µãƒãƒ¼ãƒˆåˆ‡ã‚ŒãŒé–“è¿‘ã«è¿«ã£ã¦ã„ã‚‹ã¨ã„ã†ã“ã¨ã§ã‚‚ã‚ã‚Šã¾ã™ã€‚ ãã“ã§ä»Šå›žã¯ã€æ”¹ã‚ã¦Java SE 8ã®ç†è§£ã®ãƒã‚¤ãƒ³ãƒˆã‚’è§£èª¬ã—ã‚ˆã†ã¨æ€ã„ã¾ã™ã€‚ ãƒ©ãƒ ãƒ€å¼ãƒ»Stream APIã®2ç‚¹ãŒã€Java SE 8ã®ç›®çŽ‰ã¨ãªã‚‹æ–°æ©Ÿèƒ½ã§ã™ã€‚ ã“ã‚“ãªã‚³ãƒ¼ãƒ‰ãŒå‡ºã¦ãã¾ã™ã€‚ List<Emp> source = Arrays.asList( new Emp(101, "Nishida", Dept.ADMIN, 500000), new Emp(102, "Nohira", Dept.SALES, 285000), // ä»¥ä¸‹çœç•¥ ); // ãƒ©ãƒ ãƒ€å¼ï¼†Stream APIï¼ // Empã®Listã‹ã‚‰ã€DeptãŒã€ŒSALESã€ã®è¦ç´ ã®ã¿æŠ½å‡ºã—ã€åå‰ã®ã¿ã®Listã«é›†ç´„ã™ã‚‹ List<S
snjx 2017/09/05
Stream

java

API

Java8

webã‚µãƒ¼ãƒ“ã‚¹

ã‚·ã‚¹ãƒ†ãƒ é–‹ç™º

æŠ€è¡“
ãƒªãƒ³ã‚¯
Java8ã§Java8ã£ã½ã„ã‚³ãƒ¼ãƒ‰ã‚’æ›¸ã - Qiita
æ¦‚è¦(ãŠå‰ã¯ä½•ã‚’è¨€ã£ã¦ã„ã‚‹ã‚“ã ) ã‚³ãƒ¼ãƒ‰ãƒ¬ãƒ“ãƒ¥ãƒ¼ã—ã¦ã„ã‚‹ã¨ã€__Java8ã®feature(Stream APIã¨ã‹Optionalã¨ã‹)ã‚’ä½¿ã£ã¦ã‚‹ã‚“ã ã‘ã©ã€Java7ä»¥å‰ã¨å¤§å·®ãªã„æ›¸ãæ–¹ã‚’ã•ã‚Œã¦ã„ã‚‹ã‚³ãƒ¼ãƒ‰__ã‚’ã‚ˆãè¦‹ã‹ã‘ã‚‹ã€‚ ã‚‚ã£ã¨çš†ã«__Java8ã£ã½ã„ã‚³ãƒ¼ãƒ‰__ã‚’æ›¸ã„ã¦æ¬²ã—ã„ã€‚ãã†ã˜ã‚ƒãªã„ã¨ã‚‚ã£ãŸã„ãªã„ã€‚ (*"Java8ã£ã½ã„"ã®åŸºæº–ã¯å‰²ã‚Šã¨(ã‹ãªã‚Š?)ç§è¦‹ãŒå…¥ã£ã¦ã„ã‚‹) è¨€è‘‰ã‚’å°½ãã—ã¦ã‚‚ä¼ã‚ã‚Šã¥ã‚‰ã„ã®ã§ã€ä¾‹ã‚’ä½œã‚ã†ã€‚ â† ã“ã‚Œ ã¤ã„ã§ã«ã€ã€Œç„¡ç†ã—ã¦Java8ã®featureä½¿ã†ã“ã¨ã§ã€é€†ã«æ‚ªããªã£ã¦ã—ã¾ã£ã¦ã„ã‚‹ä¾‹ã€ã‚‚ä½œã‚ã†ã€‚ å¯¾è±¡èªè€… Java8ã§ã‚³ãƒ¼ãƒ‰æ›¸ã„ã¦ã‚‹ã‘ã©ã€Java7ä»¥å‰ã®æ›¸ãæ–¹ãŒæŸ“ã¿ä»˜ã„ã¡ã‚ƒã£ã¦ã„ã¦ãªã‹ãªã‹æŠœã‘å‡ºã›ãªã„äºº ã€Œforã‚„nullãƒã‚§ãƒƒã‚¯ã¯çµ¶å¯¾ä½¿ã†ã¹ãã§ãªã„ã€ã¨ã„ã†æ€ã„ãŒå¼·ã™ãŽã¦ã€ä½•ã§ã‚‚ã‹ã‚“ã§ã‚‚Stream APIã‚„Optionalä½¿ã£ã¦ã‚‹äºº Notice
snjx 2017/08/30
Java8

java

optional

Stream

ã‚³ãƒ¼ãƒ‰

ã‚·ã‚¹ãƒ†ãƒ é–‹ç™º

è€ƒå¯Ÿ

è³‡æ–™

æŠ€è¡“

ã“ã‚Œã¯ã™ã”ã„
ãƒªãƒ³ã‚¯
[Java8] ã¯ã˜ã‚ã¦è§¦ã‚‹Streamã®ä¸–ç•Œ | DevelopersIO
æœå¹Œã¯å¤§è’ã‚Œã€ã®äºˆæƒ³ã ã£ãŸã®ã§ã™ãŒã€ä»Šã®ã¨ã“ã‚å¤§å¤‰ç©ã‚„ã‹ãªå¤©å€™ã§ã™ã€‚ã“ã‚“ã«ã¡ã¯ã€‚ã“ã‚€ã‚ã§ã™ã€‚ ã“ã®è¨˜äº‹ã¯Java Advent Calendar 2014ã®17æ—¥ç›®ã«ãªã‚Šã¾ã™ã€‚ æ˜¨æ—¥16æ—¥ã¯@zephiransasã•ã‚“ã®ã€ŒLambda-behaveã§ãƒ†ã‚¹ãƒˆã‚’æ›¸ã“ã†ã€ã§ã—ãŸã€‚ Java8ã®ç´ æ™´ã‚‰ã—ãä¸–ç•Œ Java8ã‚’ä½¿ã£ã¦ãƒ—ãƒã‚°ãƒ©ãƒŸãƒ³ã‚°ã—ã¦ã„ã‚‹ã¨ã€æ–°ã—ã„æ©Ÿèƒ½ã‚’è‰²ã€…ã¨ä½¿ã†ã“ã¨ã§ç°¡æ½”ã§èªã¿ã‚„ã™ã„ã‚³ãƒ¼ãƒ‰ã‚’è¨˜è¿°ã™ã‚‹ã“ã¨ãŒå‡ºæ¥ã¾ã™ã€‚ã“ã‚ŒãŒæ€ã„ã®å¤–æ¥½ã—ãã‚‹ã‚“ã‚‹ã‚“æ°—åˆ†ã§ã‚³ãƒ¼ãƒ‰ã‚’æ›¸ãã“ã¨ãŒå‡ºæ¥ã¾ã™ã€‚ä»Šã¾ã§ã®ã‚ˆã†ã«åž‹ã‚’ã„ã¡ã„ã¡æ›¸ã‹ãªãã‚ƒã¨ã‹ãƒã‚¹ãƒˆåœ°ç„ã¿ãŸã„ãªã¨ã“ã‚ã‚’ã€å°‘ã—ã ã‘ã€ã§ã‚‚å¤§èƒ†ã«æ”¹å–„ã™ã‚‹ã“ã¨ãŒå‡ºæ¥ã€ä¹…ã€…ã«Javaã§ã‚³ãƒ¼ãƒ‰ã‚’æ›¸ã„ã¦ã„ã¦æ¥½ã—ã„ã¨æ€ã£ãŸæ™‚é–“ã§ã—ãŸã€‚Androidã¯Javaã§ã¯ï½Žï¼ˆï½’ï½™ ç‰¹ã«ã“ã“æ•°ãƒ¶æœˆã€Play for Javaã§Java8ã‚’åˆ©ç”¨ã—ãŸé–‹ç™ºã‚’ã—ã¦ã„ãŸã®ã§ã™ãŒã€ãã®ä¸ã§Stream
snjx 2017/05/18
stream

Java8

java

è³‡æ–™

æŠ€è¡“

è€ƒå¯Ÿ

ã‚·ã‚¹ãƒ†ãƒ é–‹ç™º
ãƒªãƒ³ã‚¯
Java8ã®Streamã‚’ä»Šæ›´ãªãŒã‚‰ã¾ã¨ã‚ã¦ã¿ãŸ â€“ Javaãƒ“ãƒ¼ãƒ ç ”ç©¶æ‰€
æ›¸ãå°½ãã•ã‚Œã¦ã„ã‚‹æ°—ãŒã™ã‚‹ã‘ã©ã€è‡ªåˆ†ã®ãƒ¡ãƒ¢ã¨ã—ã¦ã¾ã¨ã‚ã¦ãŠãã¾ã™ã€‚ åŸºæœ¬ String[] array = {"AAA", "BBB", "CCC", "DDD", "EEE", "FFF"}; Stream<String> stream = Arrays.stream(array);//é…åˆ—ã‚’Streamã«å¤‰æ›ã™ã‚‹ //å…¨ã¦ã®è¦ç´ ãŒãƒ©ãƒ ãƒ€ã®æ¡ä»¶ã‚’æº€ãŸã—ã¦ã„ã‚‹ã‹ //å…¨ã¦ãŒæ¡ä»¶ã«å½“ã¦ã¯ã¾ã‚Œã°trueãŒè¿”ã‚‹ stream.allMatch(s -> s.length() == 3);//true stream.allMatch(s -> s.equals("AAA"));//false //ã„ãšã‚Œã‹ã®è¦ç´ ãŒãƒ©ãƒ ãƒ€ã®æ¡ä»¶ã‚’æº€ãŸã—ã¦ã„ã‚‹ã‹ //ã©ã‚Œã‹1ã¤ãŒæ¡ä»¶ã«å½“ã¦ã¯ã¾ã‚Œã°trueãŒè¿”ã‚‹ stream.anyMatch(s -> s.length() == 3);//true stream.an
snjx 2017/05/16
java

stream

java8

ã‚·ã‚¹ãƒ†ãƒ é–‹ç™º

æŠ€è¡“

è³‡æ–™
ãƒªãƒ³ã‚¯
Java 8 Stream API ã«ãƒ†ã‚ã‚¹ãƒˆã‚’æµã—ã¦ã¿ãŸï¼ˆçµ‚ç«¯æ“ä½œç·¨ï¼‰ - Qiita
Java 8 Stream API ã«ãƒ†ã‚ã‚¹ãƒˆã‚’æµã—ã¦ã¿ã‚‹ï¼ˆç”Ÿæˆç·¨ï¼‰- Qiita Java 8 Stream API ã«ãƒ†ã‚ã‚¹ãƒˆã‚’æµã—ã¦ã¿ãŸï¼ˆçµ‚ç«¯æ“ä½œç·¨ï¼‰- Qiita Java 8 Stream API ã«ãƒ†ã‚ã‚¹ãƒˆã‚’æµã—ã¦ã¿ã¦ï¼ˆä¸é–“æ“ä½œç·¨ï¼‰- Qiita è¦ã™ã‚‹ã«ã Java 8 Stream ã¯å®Ÿè¡Œå‰ã‚‚å®Ÿè¡Œå¾Œã‚‚ãƒ‡ãƒ¼ã‚¿ã‚’ä¿æŒã—ãªã„ã€‚ Streamã‚¯ãƒ©ã‚¹è‡ªä½“ã¯ã‚³ãƒ¬ã‚¯ã‚·ãƒ§ãƒ³ã§ã¯ãªãã€æµã‚Œã¦ãã‚‹å€‹ã€…ã®è¦ç´ ã«å¯¾ã™ã‚‹æ“ä½œã®ãƒ‘ã‚¤ãƒ—ãƒ©ã‚¤ãƒ³ã‚’æ§‹æˆã—ã¦ã„ã‚‹ã ã‘ã ã€‚å¾“ã£ã¦ Stream ã‚’é€šã—ã¦åŠ å·¥ã•ã‚ŒãŸè¦ç´ ã‚’ãƒ‡ãƒ¼ã‚¿ã¨ã—ã¦æ‰±ã†ãŸã‚ã«ã¯ã€æœ€çµ‚çš„ã«ã¾ãŸä½•ã‚‰ã‹ã®ãƒ‡ãƒ¼ã‚¿æ§‹é€ ãªã‚Šå€¤ãªã‚Šã«æˆ»ã•ã‚Œãªã‘ã‚Œã°ãªã‚‰ãªã„ã€‚ ãã®ãŸã‚ã®ãƒ¡ã‚½ãƒƒãƒ‰ç¾¤ã‚’ã€Œçµ‚ç«¯æ“ä½œ(Terminal operationï¼‰ã€ã¨å‘¼ã³ã€ãã®ã»ã‹ã®ã€Œä¸é–“æ“ä½œ(Intermediate operation)ã€ã¨åŒºåˆ¥ã™ã‚‹ã€‚ ä¸é–“æ“ä½œãƒ¡ã‚½ãƒƒãƒ‰ã¯è¦ç´ ã«é©ç”¨ã™ã‚‹é–¢æ•°ã‚’ãƒ‘
snjx 2017/05/15
ãƒ©ãƒ ãƒ€å¼

java

æŠ€è¡“

è³‡æ–™

Java8

stream

ã‚·ã‚¹ãƒ†ãƒ é–‹ç™º
ãƒªãƒ³ã‚¯
5åˆ†ã§èªã‚€å…¥é–€ç·¨ï¼šJava 8 ãƒ©ãƒ ãƒ€å¼ ã‚³ãƒ¬ã‚¯ã‚·ãƒ§ãƒ³ç·¨ï¼ˆ2ï¼‰ãƒªã‚¹ãƒˆã®æ¤œç´¢ | TECHSCORE BLOG | TECHSCORE BLOG
Java 8 ãƒ©ãƒ ãƒ€å¼ã‚’åˆ©ç”¨ã—ãŸã‚³ãƒ¬ã‚¯ã‚·ãƒ§ãƒ³ã®å‡¦ç†ã«ã¤ã„ã¦è€ƒãˆã‚‹ã€ç¬¬2å›žç›®ã§ã™ã€‚ ã“ã‚Œã¾ã§ã®è¨˜äº‹ã¯ä»¥ä¸‹ã‚’ã”è¦§ãã ã•ã„ã€‚ 5åˆ†ã§èªã‚€å…¥é–€ç·¨ï¼šJava 8 ãƒ©ãƒ ãƒ€å¼ 5åˆ†ã§èªã‚€å…¥é–€ç·¨ï¼šJava 8 ãƒ©ãƒ ãƒ€å¼ ã‚³ãƒ¬ã‚¯ã‚·ãƒ§ãƒ³ç·¨ï¼ˆ1ï¼‰ãƒªã‚¹ãƒˆã®å¤‰æ› è¦ç´ ã®æ¤œç´¢ ç‰¹å®šã®æ–‡å—ã‹ã‚‰å§‹ã¾ã‚‹è¦ç´ ã‚’æŠ½å‡ºã™ã‚‹å ´åˆã«ã¤ã„ã¦è€ƒãˆã¾ã™ã€‚ ã¾ãšã¯åœ°åã‚’æ ¼ç´ã—ãŸãƒªã‚¹ãƒˆã‚’ä½œæˆã—ã¾ã™ã€‚
snjx 2016/01/08
ãƒ©ãƒ ãƒ€å¼

java

æŠ€è¡“

è³‡æ–™

Java8

stream

ã‚·ã‚¹ãƒ†ãƒ é–‹ç™º
ãƒªãƒ³ã‚¯
1