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Java8ã«é–¢ã™ã‚‹chess-newsã®ãƒ–ãƒƒã‚¯ãƒžãƒ¼ã‚¯ (16)

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ä»Šæ›´ãªãŒã‚‰Java8ã«ã¤ã„ã¦ã¾ã¨ã‚ã¦ã¿ãŸ - Qiita
ã¯ã˜ã‚ã« Java11ãŒå…¬å¼ãƒªãƒªãƒ¼ã‚¹ã•ã‚Œã¦2ã‹æœˆãã‚‰ã„ãŒçµŒã¡ã¾ã—ãŸã€‚ JDKã®æœ‰å„ŸåŒ–ãªã©è‰²ã€…ãªæ„å‘³ã§å¤‰åŒ–ã—ã¦ã„ãJavaã§ã™ãŒã€ ã“ã“ã§åŸºæœ¬ã«ç«‹ã¡è¿”ã£ã¦ã€Java8ã«ã¤ã„ã¦ã¾ã¨ã‚ã¦ã¿ã¾ã—ãŸã€‚ ä¸»ã«ã‚ˆãä½¿ç”¨ã™ã‚‹æ©Ÿèƒ½ã«ã¤ã„ã¦è¨˜è¼‰ã—ã¦ã„ãã¾ã™ã€‚ å› ã¿ã«ç†è€…ã¯å‰ã®ç¾å ´ã¾ã§ã¯Java7ã—ã‹çµŒé¨“ãŒãªãã€ Java8æ´ã¯åŠå¹´ãã‚‰ã„ã§ã™ã€‚ ã‚ˆãä½¿ç”¨ã™ã‚‹è¿½åŠ ã•ã‚ŒãŸæ©Ÿèƒ½ Lambda(ãƒ©ãƒ ãƒ€å¼) Optional Stream ãã‚Œã§ã¯è©³ã—ãè¦‹ã¦ã„ãã¾ã—ã‚‡ã†ã€‚ Lambda(ãƒ©ãƒ ãƒ€å¼) åˆ¥åã§ã¯ã‚¯ãƒãƒ¼ã‚¸ãƒ£(Closure)ã¨ã‚‚å‘¼ã°ã‚Œã¦ã„ã‚‹ã‚‰ã—ã„ã§ã™ã€‚(ãã†å‘¼ã¶äººé–“ã‚’è¦‹ãŸã“ã¨ã‚ã‚Šã¾ã›ã‚“ãŒï¼‰ ã©ã‚“ãªã‚‚ã®ã‹å®Ÿéš›ã®è¨˜è¿°ã‚’è¦‹ã¦ã¿ã¾ã—ã‚‡ã†ã€‚ â€¦ã ã‹ã‚‰ãªã‚“ã‚„ãã‚“ã€ã¦æ„Ÿã˜ã§ã™ã‚ˆãã€‚ ãã‚‚ãã‚‚ãƒ©ãƒ ãƒ€å¼ã¨ã¯ ãã‚‚ãã‚‚ãƒ©ãƒ ãƒ€å¼ãŒä½•ãªã®ã‹ã¨ã„ã†ã¨ã€ é–¢æ•°åž‹ã‚¤ãƒ³ã‚¿ãƒ¼ãƒ•ã‚§ãƒ¼ã‚¹ã®å®Ÿè£…ã‚’å¼ã¨ã—ã¦ç°¡æ½”ã«è¨˜è¿°ã§ãã‚‹æ©Ÿèƒ½ã§ã™ã€‚ â€¦ã¾ãŸé–¢æ•°åž‹ã‚¤ãƒ³ã‚¿
chess-news 2019/08/11
Optional Stream

java

java8
ãƒªãƒ³ã‚¯
ã‚³ãƒ¬ã‚¯ã‚·ãƒ§ãƒ³ã‚’å¼·åŒ–ã—ãŸStream - Qiita
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chess-news 2019/07/04
java

stream

java8
ãƒªãƒ³ã‚¯
forã‚„ifã§æ›¸ãã‚¢ãƒ¬ã‚’Stream APIã§æ›¸ã - è¡Œãã‚ãŸã‚Šã°ã£ãŸã‚Šã‚¨ãƒ³ã‚¸ãƒ‹ã‚¢ã®æ—¥è¨˜
å‰å›žã®ç¶šç·¨ã§ã™ã€‚ å‰å›žã®è¨˜äº‹â†“ Stream APIã«ãƒãƒ£ãƒ¬ãƒ³ã‚¸ï¼ - Java EE äº‹å§‹ã‚ï¼ Java SE 8ãƒãƒ¼ãƒ³ãƒã‚¤ãƒ™ãƒ³ãƒˆã§ã®@cero_tã•ã‚“ã®ç™ºè¡¨ã®ä¸ã§ã€æ–°ã—ã„å®šçŸ³ã¨ã—ã¦ ã€Œforã‚„whileã‚’è¦‹ã‹ã‘ãŸã‚‰Stream APIã¸ã®ç½®ãæ›ãˆã‚’è€ƒãˆã‚‹ã€ ã¨ã„ã†ã®ãŒã‚ã‚Šã¾ã—ãŸã€‚ä»Šå›žã¯ã“ã‚Œã«ãƒãƒ£ãƒ¬ãƒ³ã‚¸ã—ã‚ˆã†ã¨æ€ã„ã¾ã™ã€‚ 1ï½ž20ã¾ã§ã®å¶æ•°ã®ã¿ã®åˆè¨ˆã‚’æ±‚ã‚ã‚‹ï¼ˆç”ã¯110ï¼‰ Java 7ã¾ã§ã®æ›¸ãæ–¹ int sum1 = 0; for (int i = 1; i <= 20; i++) { if (i % 2 == 0) { sum1 += i; } } System.out.println(sum1); Java 8ã§ã®æ›¸ãæ–¹â‘ int sum2 = IntStream.rangeClosed(1, 20) .filter(i -> i % 2 == 0) .sum(); System.
chess-news 2019/07/04
java8

java
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
chess-news 2019/06/26
Stream

Java8

lambda

java

api
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
chess-news 2019/06/26
Java8

java

Stream
ãƒªãƒ³ã‚¯
10ã®Java9ã§å¤‰ã‚ã‚‹Java8ã®å«Œãªã¨ã“ï¼
6. ã‚³ãƒ³ãƒ‘ã‚¤ãƒ«ã«æ™‚é–“ã‹ã‹ã‚Šã™ãŽ class C<T> { C() {} C(T t) {} C(C<T> c) {} static <U> C<U> m(C<U> c) {return c;} public static void main(String... args) { C<String> c = m(new C<>(m(new C<>(m(new C<>())))); // 1ç§’ä»¥ä¸‹ } }
chess-news 2019/02/17
java

java9

Java8

javaFukuoka
ãƒªãƒ³ã‚¯
Java8è¶…å…¥é–€ - foræ–‡ã®ä»£ã‚ã‚Šã«Streamã‚’ä½¿ãŠã†(3) - ã‚¨ãƒ³ã‚¿ãƒ¼ãƒ—ãƒ©ã‚¤ã‚ºã‚®ãƒ¼ã‚¯ã‚¹ (Enterprise Geeks)
å‰å›žã®è¨˜äº‹ã§ã¯ã€Stream APIã®filterãƒ¡ã‚½ãƒƒãƒ‰ã‚’ä½¿ã£ã¦ã€é›†åˆãƒ‡ãƒ¼ã‚¿ã‹ã‚‰æ¡ä»¶ã«åˆè‡´ã™ã‚‹è¦ç´ ã‚’æŠ½å‡ºã™ã‚‹æ–¹æ³•ã‚’ç´¹ä»‹ã—ãŸã€‚ ä»Šå›žã¯é›†åˆãƒ‡ãƒ¼ã‚¿å†…ã®è¦ç´ ã‚’å¤‰æ›ã™ã‚‹mapãƒ¡ã‚½ãƒƒãƒ‰ã‚’ç´¹ä»‹ã™ã‚‹ã€‚ ã“ã‚Œã¾ã§ã¨åŒæ§˜ã«ã€ã‚·ãƒ³ãƒ—ãƒ«ãªPersonã‚¯ãƒ©ã‚¹ã‚’åˆ©ç”¨ã™ã‚‹ã€‚ public class Person { private String name; private boolean maleFlag; private int age; public String getName() { return this.name; } public boolean isMale() { return this.maleFlag; } public int getAge() { return this.age; } public Person(String name, boolean maleFlag, int age
chess-news 2019/02/17
ã€€stream

Java8

java
ãƒªãƒ³ã‚¯
Java8ã®Streamã‚’ä½¿ã„ã“ãªã™ - ãã—ã ã®Hatena
ã•ã¦ã€Java8ã§é–¢æ•°åž‹ã£ã½ã„ã“ã¨ã‚’ã‚„ã£ã¦éŠã‚“ã§ã¿ãŸã‚ã‘ã§ã™ãŒã€å®Ÿéš›ã¯ãã‚“ãªæ›¸ãæ–¹ã—ã¾ã›ã‚“ã‚ˆãã€‚ Java8ã§å®Ÿéš›ã«ä½¿ã†ã®ã¯ã€Streamã§ã™ã€‚ ã¨ã„ã†ã“ã¨ã§ã€Streamã®ä½¿ã„æ–¹ã‚’ã²ã¨ã¨ãŠã‚Šè¦‹ã¦ã¿ã¾ã™ã€‚ â€»5/17 ä»•æ§˜å¤‰æ›´ãŒã‚ã£ãŸã®ã§ã€ä¿®æ£ã—ã¾ã—ãŸ åŸºæœ¬ ã¾ãšã¯ã€Iterableã‚¤ãƒ³ã‚¿ãƒ•ã‚§ãƒ¼ã‚¹ã«ç”¨æ„ã•ã‚ŒãŸforEachãƒ¡ã‚½ãƒƒãƒ‰ã‚’è¦‹ã¦ã¿ã¾ã—ã‚‡ã†ã€‚ List<String> names = Arrays.asList("hoge hoge", "foo bar", "naoki", "kishida"); names.forEach(s -> System.out.println(s)); ã“ã‚Œã§æ¬¡ã®ã‚ˆã†ã«è¡¨ç¤ºã•ã‚Œã¾ã™ã€‚ hoge hoge foo bar naoki kishida ã„ã¾ã¾ã§ã®æ‹¡å¼µforã ã¨æ¬¡ã®ã‚ˆã†ã«æ›¸ã„ã¦ã¾ã—ãŸ List<String> names = Arrays.a
chess-news 2019/02/11
stream

java

java8
ãƒªãƒ³ã‚¯
Java8ã§å¼·åŒ–ã•ã‚ŒãŸMapã¨ã€æ›¸ãã‚„ã™ããªã£ãŸãƒ¡ãƒ¢åŒ–å†å¸° - ãã—ã ã®Hatena
Java8ã®lambdaæ§‹æ–‡ã®è©±ã‚’æ›¸ãã¨ã€æ—§æ¥ã®æ›¸ãæ–¹ã§ã„ã„ã¨ã„ã†ã‚³ãƒ¡ãƒ³ãƒˆãŒã¤ãã®ã§ã™ãŒã€ãã‚Œã§ã‚‚ä¾¿åˆ©ã«ãªã£ãŸMapã®æ©æµã‚’å—ã‘ã‚‹ã“ã¨ã¯å¤šã„ã‚“ã˜ã‚ƒãªã„ã‹ã¨æ€ã„ã¾ã™ã€‚ â€» 2018/5/31 Java9ã‹ã‚‰ã¯ãƒ¡ãƒ¢åŒ–å†å¸°ã«ã¯ä½¿ãˆãªããªã£ã¦ã„ã¾ã™ â€» 2019/2/15 ãªã‚“ã‹å•é¡Œãªã„ï¼Ÿ Mapã«ã¯ã€lambdaå¼ã‚’ä½¿ã£ãŸãƒ¡ã‚½ãƒƒãƒ‰ãŒå¤šãè¿½åŠ ã•ã‚Œã¦ã„ã¾ã™ãŒã€ãŸã¨ãˆã°getOrDefaultãƒ¡ã‚½ãƒƒãƒ‰ã®ã‚ˆã†ãªlambdaå¼ã‚’ä½¿ã‚ãªã„ãƒ¡ã‚½ãƒƒãƒ‰ã‚‚è¿½åŠ ã•ã‚Œã¦ã„ã¦ã€ã“ã‚Œã‚‚ä¾¿åˆ©ã§ã™ã€‚ ãã—ã¦ã€ã“ã®ã‚ˆã†ãªlambdaå¼ã‚’ä½¿ã‚ãªã„ãƒ¡ã‚½ãƒƒãƒ‰ã‚‚ã€é–“æŽ¥çš„ã«ã¯lambdaæ§‹æ–‡ã‚µãƒãƒ¼ãƒˆã§ã®è¨€èªžæ‹¡å¼µã®ãŠã‹ã’ã§ã™ã€‚ Mapã¯ã‚¤ãƒ³ã‚¿ãƒ•ã‚§ãƒ¼ã‚¹ãªã®ã§ã€Java7ã¾ã§ã®æ§‹æ–‡ã§ãƒ¡ã‚½ãƒƒãƒ‰ã‚’è¿½åŠ ã—ã‚ˆã†ã¨ã™ã‚‹ã¨ã€Mapã‚’å®Ÿè£…ã—ã¦ã„ã‚‹ã™ã¹ã¦ã®ã‚¯ãƒ©ã‚¹ã«æ–°ã—ã„ãƒ¡ã‚½ãƒƒãƒ‰ã®å®Ÿè£…ã‚’è¿½åŠ ã™ã‚‹å¿…è¦ãŒã‚ã‚Šã¾ã—ãŸã€‚ãã—ã¦ãã‚Œã¯ç¾å®Ÿçš„ã«ä¸å¯èƒ½ãªã®ã§ã€ä»Šã¾ã§Mapãªã©
chess-news 2019/02/11
java8

lambda

map
ãƒªãƒ³ã‚¯
Java8ã§æœ€ã‚‚ã‚¤ãƒ³ãƒ‘ã‚¯ãƒˆã®ã‚ã‚‹æ§‹æ–‡æ‹¡å¼µã€ãƒ‡ãƒ•ã‚©ãƒ«ãƒˆãƒ¡ã‚½ãƒƒãƒ‰ - ãã—ã ã®Hatena
Java8ã§ã®ãƒ©ãƒ ãƒ€ã®ä½¿ã„æ–¹ãªã©ã‚’èª¬æ˜Žã—ã¦ããŸã®ã§ã™ãŒã€æ§‹æ–‡æ‹¡å¼µè‡ªä½“ã«ã¯è§¦ã‚Œã¦ã„ãªã‹ã£ãŸã®ã§ã€æ”¹ã‚ã¦ã“ã“ã§ç°¡å˜ã«èª¬æ˜Žã—ã¦ãŠã“ã†ã¨æ€ã„ã¾ã™ã€‚ ã¾ãšã¯ã€Java8ã§å®Ÿéš›ã«æœ€ã‚‚ã‚¤ãƒ³ãƒ‘ã‚¯ãƒˆãŒã‚ã‚‹è¨€èªžæ‹¡å¼µã€ã‚¤ãƒ³ã‚¿ãƒ•ã‚§ãƒ¼ã‚¹ã®ãƒ‡ãƒ•ã‚©ãƒ«ãƒˆãƒ¡ã‚½ãƒƒãƒ‰ã§ã™ã€‚ ãƒ‡ãƒ•ã‚©ãƒ«ãƒˆãƒ¡ã‚½ãƒƒãƒ‰ã¨ãƒ‡ãƒ•ã‚©ãƒ«ãƒˆå®Ÿè£… ã„ã¾ã¾ã§ã‚¤ãƒ³ã‚¿ãƒ•ã‚§ãƒ¼ã‚¹ã«ã¯å®Ÿè£…ã‚’ã‚‚ã¤ã“ã¨ãŒã§ãã¾ã›ã‚“ã§ã—ãŸãŒã€Java 8ã‹ã‚‰ã¯ã‚¤ãƒ³ã‚¿ãƒ•ã‚§ãƒ¼ã‚¹ãŒå®Ÿè£…ã‚’ã‚‚ã¦ã‚‹ã‚ˆã†ã«ãªã‚Šã¾ã™ã€‚ å®Ÿè£…ã‚’ã‚‚ã¤ãƒ¡ã‚½ãƒƒãƒ‰ã‚’å®šç¾©ã™ã‚‹ã¨ãã«ã¯ã€ã‚ãƒ¼ãƒ¯ãƒ¼ãƒ‰defaultã‚’ãƒ¡ã‚½ãƒƒãƒ‰ã®å‰ã«ã¤ã‘ã¾ã™ã€‚ interface Foo{ void print(String s); default void twice(String s){ print(s); print(s); } } twiceãƒ¡ã‚½ãƒƒãƒ‰ãŒå®Ÿè£…ã‚’ã‚‚ã£ã¦ã„ã¾ã™ã€‚ã“ã®å®Ÿè£…ã‚’ãƒ‡ãƒ•ã‚©ãƒ«ãƒˆå®Ÿè£…ã¨ã„ã„ã¾ã™ã€‚ ãƒ‡ãƒ•ã‚©ãƒ«ãƒˆãƒ¡ã‚½ãƒƒãƒ‰ã‚’å®Ÿè£…ã™ã‚‹ã‚¯ãƒ©ã‚¹ã§ã€ãƒ‡ãƒ•ã‚©ãƒ«ãƒˆãƒ¡
chess-news 2019/02/11
java

java8

programming

interface
ãƒªãƒ³ã‚¯
Java8 Lambdaã®æ–‡æ³•æ‹¡å¼µã¾ã¨ã‚ - ãã—ã ã®Hatena
ãƒ‡ãƒ•ã‚©ãƒ«ãƒˆãƒ¡ã‚½ãƒƒãƒ‰ã¯å‰ã«è§£èª¬ã—ã¾ã—ãŸã€‚ Java8ã§æœ€ã‚‚ã‚¤ãƒ³ãƒ‘ã‚¯ãƒˆã®ã‚ã‚‹æ§‹æ–‡æ‹¡å¼µã€ãƒ‡ãƒ•ã‚©ãƒ«ãƒˆãƒ¡ã‚½ãƒƒãƒ‰ ã“ã“ã§ã¯ã€ãã‚Œä»¥å¤–ã®æ§‹æ–‡æ‹¡å¼µã«ã¤ã„ã¦ã¾ã¨ã‚ã¦ãŠãã¾ã™ã€‚ ãƒ©ãƒ ãƒ€å¼ å®Ÿè£…ã™ã¹ããƒ¡ã‚½ãƒƒãƒ‰ãŒã²ã¨ã¤ã ã‘ã®ã‚¤ãƒ³ã‚¿ãƒ•ã‚§ãƒ¼ã‚¹ã‚’é–¢æ•°åž‹ã‚¤ãƒ³ã‚¿ãƒ•ã‚§ãƒ¼ã‚¹ã¨ã„ã„ã¾ã™ã€‚ UnaryOperatorã‚¤ãƒ³ã‚¿ãƒ•ã‚§ãƒ¼ã‚¹ã¯å®Ÿè£…ã™ã¹ããƒ¡ã‚½ãƒƒãƒ‰ãŒapplyãƒ¡ã‚½ãƒƒãƒ‰ã²ã¨ã¤ã ã‘ãªã®ã§ã€é–¢æ•°åž‹ã‚¤ãƒ³ã‚¿ãƒ•ã‚§ãƒ¼ã‚¹ã«ãªã‚Šã¾ã™ã€‚ ãŸã¨ãˆã°ã€UnaryOperatorã‚¤ãƒ³ã‚¿ãƒ•ã‚§ãƒ¼ã‚¹ã‚’å®Ÿè£…ã—ãŸã‚¯ãƒ©ã‚¹ã‚’å®šç¾©ã™ã‚‹ã¨æ¬¡ã®ã‚ˆã†ã«ãªã‚Šã¾ã™ã€‚ class MyOp implements UnaryOperator<String>{ @Override public String apply(String t) { return "** " + t + " **"; } } ã“ã®UnaryOperatorã‚¤ãƒ³ã‚¿ãƒ•ã‚§ãƒ¼ã‚¹ã‚’ä½¿ã†ã€List#replaceAllã‚’
chess-news 2019/02/11
java

java8

list

lambda

programming

Java SE 8
ãƒªãƒ³ã‚¯
Java8ã®ãƒ©ãƒ ãƒ€å¼ã‚’ç†è§£ã™ã‚‹ - Qiita
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chess-news 2019/02/11
ãƒ©ãƒ ãƒ€å¼

java8

java
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chess-news 2019/02/10
java8

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Java 8u60ã§ã€Mapã®åˆæœŸåŒ–ã¨ã‹ãŒã™ã”ã„æ¥½ã«ãªã£ã¦ã‚‹ä»¶ - mike-neckã®ãƒ–ãƒã‚°
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chess-news 2018/10/06
HashMap

programming

java

map

hash

java8
ãƒªãƒ³ã‚¯
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chess-news 2018/08/03
HashMap

performance

hashtable

java

java8

programming

hash
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chess-news 2018/08/03
algorithm

ã‚¢ãƒ«ã‚´ãƒªã‚ºãƒ

Java8

java

hash
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