Stream\uff08\u6d41\uff09\u662f\u4e00\u4e2a\u6765\u81ea\u6570\u636e\u6e90\u7684\u5143\u7d20\u961f\u5217\u5e76\u652f\u6301\u805a\u5408\u64cd\u4f5c<\/p>\n
\u548c\u4ee5\u524d\u7684Collection\u64cd\u4f5c\u4e0d\u540c\uff0c Stream\u64cd\u4f5c\u8fd8\u6709\u4e24\u4e2a\u57fa\u7840\u7684\u7279\u5f81\uff1a<\/p>\n
filter()\uff1a\u5bf9\u5143\u7d20\u8fdb\u884c\u8fc7\u6ee4\r\nmap()\uff1a\u5c06\u6d41\u7684\u5143\u7d20\u6620\u5c04\u6210\u53e6\u4e00\u4e2a\u7c7b\u578b\r\ndistinct()\uff1a\u53bb\u9664\u6d41\u4e2d\u91cd\u590d\u7684\u5143\u7d20\r\nsorted()\uff1a\u5bf9\u5143\u7d20\u8fdb\u884c\u6392\u5e8f\r\nforEach \uff1a\u5bf9\u6d41\u4e2d\u7684\u6bcf\u4e2a\u5143\u7d20\u6267\u884c\u67d0\u4e2a\u64cd\u4f5c\r\npeek()\uff1a\u4e0eforEach()\u65b9\u6cd5\u6548\u679c\u7c7b\u4f3c\uff0c\u4e0d\u540c\u7684\u662f\uff0c\u8be5\u65b9\u6cd5\u4f1a\u8fd4\u56de\u4e00\u4e2a\u65b0\u7684\u6d41\uff0c\u800cforEach()\u65e0\u8fd4\u56de\r\nlimit()\uff1a\u622a\u53d6\u6d41\u4e2d\u524d\u9762\u51e0\u4e2a\u5143\u7d20\r\nskip()\uff1a\u8df3\u8fc7\u6d41\u4e2d\u524d\u9762\u51e0\u4e2a\u5143\u7d20\r\ntoArray()\uff1a\u5c06\u6d41\u8f6c\u6362\u4e3a\u6570\u7ec4\r\nreduce()\uff1a\u5bf9\u6d41\u4e2d\u7684\u5143\u7d20\u5f52\u7ea6\u64cd\u4f5c\uff0c\u5c06\u6bcf\u4e2a\u5143\u7d20\u5408\u8d77\u6765\u5f62\u6210\u4e00\u4e2a\u65b0\u7684\u503c\r\ncollect()\uff1a\u5bf9\u6d41\u7684\u6c47\u603b\u64cd\u4f5c\uff0c\u6bd4\u5982\u8f93\u51fa\u6210List\u96c6\u5408\r\nanyMatch()\uff1a\u5339\u914d\u6d41\u4e2d\u7684\u5143\u7d20\uff0c\u7c7b\u4f3c\u7684\u64cd\u4f5c\u8fd8\u6709allMatch()\u548cnoneMatch()\u65b9\u6cd5\r\nfindFirst()\uff1a\u67e5\u627e\u7b2c\u4e00\u4e2a\u5143\u7d20\uff0c\u7c7b\u4f3c\u7684\u8fd8\u6709findAny()\u65b9\u6cd5\r\nmax()\uff1a\u6c42\u6700\u5927\u503c\r\nmin()\uff1a\u6c42\u6700\u5c0f\u503c\r\ncount()\uff1a\u6c42\u603b\u6570\r\n<\/code><\/pre>\n\u6d41\u7684\u64cd\u4f5c\u7c7b\u578b<\/h3>\n
\u6d41\u7684\u64cd\u4f5c\u7c7b\u578b\u4e3b\u8981\u5206\u4e3a\u4e24\u79cd<\/p>\n
\n- \u4e2d\u95f4\u64cd\u4f5c \u4e00\u4e2a\u6d41\u53ef\u4ee5\u540e\u9762\u8ddf\u968f\u96f6\u4e2a\u6216\u591a\u4e2a\u4e2d\u95f4\u64cd\u4f5c\u3002\u5176\u76ee\u7684\u4e3b\u8981\u662f\u6253\u5f00\u6d41\uff0c\u505a\u51fa\u67d0\u79cd\u7a0b\u5ea6\u7684\u6570\u636e\u6620\u5c04\/\u8fc7\u6ee4\uff0c\u7136\u540e\u8fd4\u56de\u4e00\u4e2a\u65b0\u7684\u6d41\uff0c\u4ea4\u7ed9\u4e0b\u4e00\u4e2a\u64cd\u4f5c\u4f7f\u7528\u3002\u8fd9\u7c7b\u64cd\u4f5c\u90fd\u662f\u60f0\u6027\u5316\u7684\uff0c\u4ec5\u4ec5\u8c03\u7528\u5230\u8fd9\u7c7b\u65b9\u6cd5\uff0c\u5e76\u6ca1\u6709\u771f\u6b63\u5f00\u59cb\u6d41\u7684\u904d\u5386\uff0c\u771f\u6b63\u7684\u904d\u5386\u9700\u7b49\u5230\u7ec8\u7aef\u64cd\u4f5c\u65f6\uff0c\u5e38\u89c1\u7684\u4e2d\u95f4\u64cd\u4f5c\u6709\u4e0b\u9762\u5373\u5c06\u4ecb\u7ecd\u7684
filter<\/code>\u3001map<\/code>\u7b49<\/li>\n- \u7ec8\u7aef\u64cd\u4f5c \u4e00\u4e2a\u6d41\u6709\u4e14\u53ea\u80fd\u6709\u4e00\u4e2a\u7ec8\u7aef\u64cd\u4f5c\uff0c\u5f53\u8fd9\u4e2a\u64cd\u4f5c\u6267\u884c\u540e\uff0c\u6d41\u5c31\u88ab\u5173\u95ed\u4e86\uff0c\u65e0\u6cd5\u518d\u88ab\u64cd\u4f5c\uff0c\u56e0\u6b64\u4e00\u4e2a\u6d41\u53ea\u80fd\u88ab\u904d\u5386\u4e00\u6b21\uff0c\u82e5\u60f3\u5728\u904d\u5386\u9700\u8981\u901a\u8fc7\u6e90\u6570\u636e\u5728\u751f\u6210\u6d41\u3002\u7ec8\u7aef\u64cd\u4f5c\u7684\u6267\u884c\uff0c\u624d\u4f1a\u771f\u6b63\u5f00\u59cb\u6d41\u7684\u904d\u5386\u3002\u5982\u4e0b\u9762\u5373\u5c06\u4ecb\u7ecd\u7684
count<\/code>\u3001collect<\/code>\u7b49<\/li>\n<\/ul>\n\u5728 Java 8 \u4e2d, \u96c6\u5408\u63a5\u53e3\u6709\u4e24\u4e2a\u65b9\u6cd5\u6765\u751f\u6210\u6d41\uff1a<\/p>\n
\n- stream()<\/strong> \u2212 \u4e3a\u96c6\u5408\u521b\u5efa\u4e32\u884c\u6d41\u3002<\/li>\n
- parallelStream()<\/strong> \u2212 \u4e3a\u96c6\u5408\u521b\u5efa\u5e76\u884c\u6d41\u3002<\/li>\n<\/ul>\n
\u4e32\u884c\uff08stream\uff09\u7a0b\u5e8f<\/h4>\nList<String> lists = Arrays.asList(\"1\", \"2\", \"3\", \"\");\r\nlists.stream()\r\n\t.filter(list -> !list.isEmpty())\r\n\t.collect(Collectors.toList())\r\n\t.forEach(s -> System.out.println(\"s:\"+s));\r\n<\/code><\/pre>\n\u5e76\u884c\uff08parallel\uff09\u7a0b\u5e8f<\/h4>\n
parallelStream \u662f\u6d41\u5e76\u884c\u5904\u7406\u7a0b\u5e8f\u7684\u4ee3\u66ff\u65b9\u6cd5\u3002\u4ee5\u4e0b\u5b9e\u4f8b\u6211\u4eec\u4f7f\u7528 parallelStream \u6765\u8f93\u51fa\u7a7a\u5b57\u7b26\u4e32\u7684\u6570\u91cf\uff1a<\/p>\n
List<String> strings = Arrays.asList(\"abc\", \"\", \"bc\", \"efg\", \"abcd\",\"\", \"jkl\");\r\n\/\/ \u83b7\u53d6\u7a7a\u5b57\u7b26\u4e32\u7684\u6570\u91cf\r\nlong count = strings.parallelStream().filter(s -> s.isEmpty()).count();\r\nSystem.out.println(\"count:\"+count);\r\n<\/code><\/pre>\n####<\/p>\n
\u4e2d\u95f4\u64cd\u4f5c<\/h3>\nforEach<\/h4>\n
Stream \u63d0\u4f9b\u4e86\u65b0\u7684\u65b9\u6cd5 ‘forEach’ \u6765\u8fed\u4ee3\u6d41\u4e2d\u7684\u6bcf\u4e2a\u6570\u636e\u3002\u4ee5\u4e0b\u4ee3\u7801\u7247\u6bb5\u4f7f\u7528 forEach \u8f93\u51fa\u4e8610\u4e2a\u968f\u673a\u6570\uff1a<\/p>\n
Random random = new Random();\r\n\/\/ random.ints().limit(10).forEach(num -> System.out.println(\"num:\"+num));\r\nrandom.ints().limit(10).forEach(System.out::println);\r\n<\/code><\/pre>\nCollectors<\/h4>\n
Collectors \u7c7b\u5b9e\u73b0\u4e86\u5f88\u591a\u5f52\u7ea6\u64cd\u4f5c\uff0c\u4f8b\u5982\u5c06\u6d41\u8f6c\u6362\u6210\u96c6\u5408\u548c\u805a\u5408\u5143\u7d20\u3002Collectors \u53ef\u7528\u4e8e\u8fd4\u56de\u5217\u8868\u6216\u5b57\u7b26\u4e32\uff1a<\/p>\n
List<String>strings = Arrays.asList(\"abc\", \"\", \"bc\", \"efg\", \"abcd\",\"\", \"jkl\");\r\nList<String> filtered = strings.stream().filter(string -> !string.isEmpty()).collect(Collectors.toList());\r\n\r\nSystem.out.println(\"\u7b5b\u9009\u5217\u8868: \" + filtered);\r\nString mergedString = strings.stream().filter(string -> !string.isEmpty()).collect(Collectors.joining(\", \"));\r\nSystem.out.println(\"\u5408\u5e76\u5b57\u7b26\u4e32: \" + mergedString);\r\n<\/code><\/pre>\nmap<\/h4>\n
\u6240\u8c13\u6d41\u6620\u5c04\u5c31\u662f\u5c06\u63a5\u53d7\u7684\u5143\u7d20\u6620\u5c04\u6210\u53e6\u5916\u4e00\u4e2a\u5143\u7d20<\/p>\n
map \u65b9\u6cd5\u7528\u4e8e\u6620\u5c04\u6bcf\u4e2a\u5143\u7d20\u5230\u5bf9\u5e94\u7684\u7ed3\u679c\uff0c\u4ee5\u4e0b\u4ee3\u7801\u7247\u6bb5\u4f7f\u7528 map \u8f93\u51fa\u4e86\u5143\u7d20\u5bf9\u5e94\u7684\u5e73\u65b9\u6570\uff1a<\/p>\n
List<Integer> numbers = Arrays.asList(1, 2, 3, 4, 5);\r\nnumbers.stream()\r\n\t.map(i -> i*i)\r\n\t.distinct()\r\n\t.collect(Collectors.toList())\r\n\t.forEach(System.out::println);\r\n<\/code><\/pre>\nfilter\u7b5b\u9009<\/strong><\/h4>\nfilter \u65b9\u6cd5\u7528\u4e8e\u901a\u8fc7\u8bbe\u7f6e\u7684\u6761\u4ef6\u8fc7\u6ee4\u51fa\u5143\u7d20\u3002\u4ee5\u4e0b\u4ee3\u7801\u7247\u6bb5\u4f7f\u7528 filter \u65b9\u6cd5\u8fc7\u6ee4\u51fa\u7a7a\u5b57\u7b26\u4e32\uff1a<\/p>\n
List<String> strings = Arrays.asList(\"1\", \"\", \"2\", \"aa\");\r\nlong count = strings.stream().filter(s -> s.isEmpty()).count();\r\n<\/code><\/pre>\n\u901a\u8fc7\u4f7f\u7528filter<\/code>\u65b9\u6cd5\u8fdb\u884c\u6761\u4ef6\u7b5b\u9009\uff0cfilter<\/code>\u7684\u65b9\u6cd5\u53c2\u6570\u4e3a\u4e00\u4e2a\u6761\u4ef6:<\/p>\nList<Integer> integers = Arrays.asList(1, 1, 2, 3, 4, 5);\r\nintegers.stream()\r\n .filter(i -> i>3)\r\n .collect(Collectors.toList())\r\n .forEach(System.out::println);\r\n<\/code><\/pre>\n <\/p>\n
List<String> stringList = Arrays.asList(\"Java 8\", \"Lambdas\", \"In\", \"Action\");\r\nstringList.stream()\r\n .map(String::length)\r\n .collect(Collectors.toList())\r\n .forEach(System.out::println);\r\n<\/code><\/pre>\n\u901a\u8fc7map<\/code>\u65b9\u6cd5\u53ef\u4ee5\u5b8c\u6210\u6620\u5c04\uff0c\u8be5\u4f8b\u5b50\u5b8c\u6210\u4e2dString -> Integer<\/code>\u7684\u6620\u5c04\uff0c\u4e4b\u524d\u4e0a\u9762\u7684\u4f8b\u5b50\u901a\u8fc7map<\/code>\u65b9\u6cd5\u5b8c\u6210\u4e86Dish->String<\/code>\u7684\u6620\u5c04<\/p>\nflatMap\u6d41\u8f6c\u6362<\/h4>\n
\u5c06\u4e00\u4e2a\u6d41\u4e2d\u7684\u6bcf\u4e2a\u503c\u90fd\u8f6c\u6362\u4e3a\u53e6\u4e00\u4e2a\u6d41<\/p>\n
List<String> wordList = Arrays.asList(\"Hello\", \"World\");\r\nwordList.stream()\r\n .map(w -> w.split(\" \"))\r\n .flatMap(Arrays::stream)\r\n .distinct()\r\n .collect(Collectors.toList()).forEach(System.out::println);\r\n<\/code><\/pre>\ndistinct\u53bb\u9664\u91cd\u590d\u5143\u7d20<\/strong><\/h4>\n\u901a\u8fc7distinct<\/code>\u65b9\u6cd5\u5feb\u901f\u53bb\u9664\u91cd\u590d\u7684\u5143\u7d20<\/p>\nList<Integer> integers = Arrays.asList(1, 1, 2, 3, 4, 5);\r\nintegers.stream()\r\n .distinct()\r\n .collect(Collectors.toList())\r\n .forEach(System.out::println);\r\n<\/code><\/pre>\nlimit\u8fd4\u56de\u6307\u5b9a\u6d41\u4e2a\u6570<\/strong><\/h4>\n\u8fc7limit<\/code>\u65b9\u6cd5\u6307\u5b9a\u8fd4\u56de\u6d41\u7684\u4e2a\u6570\uff0climit<\/code>\u7684\u53c2\u6570\u503c\u5fc5\u987b>=0<\/code>\uff0c\u5426\u5219\u5c06\u4f1a\u629b\u51fa\u5f02\u5e38<\/p>\nlimit \u65b9\u6cd5\u7528\u4e8e\u83b7\u53d6\u6307\u5b9a\u6570\u91cf\u7684\u6d41\u3002 \u4ee5\u4e0b\u4ee3\u7801\u7247\u6bb5\u4f7f\u7528 limit \u65b9\u6cd5\u6253\u5370\u51fa 10 \u6761\u6570\u636e\uff1a<\/p>\n
Random random = new Random();\r\n\/\/ random.ints().limit(10).forEach(num -> System.out.println(\"num:\"+num));\r\nrandom.ints().limit(10).forEach(System.out::println);\r\n<\/code><\/pre>\nList<Integer> integers = Arrays.asList(1, 1, 2, 3, 4, 5);\r\nintegers.stream()\r\n .limit(3)\r\n .collect(Collectors.toList())\r\n .forEach(System.out::println);\r\n<\/code><\/pre>\nskip\u8df3\u8fc7\u6d41\u4e2d\u7684\u5143\u7d20<\/strong><\/h4>\nList<Integer> integers = Arrays.asList(1, 1, 2, 3, 4, 5);\r\nintegers.stream()\r\n .skip(2)\r\n .collect(Collectors.toList())\r\n .forEach(System.out::println);\r\n<\/code><\/pre>\n\u901a\u8fc7skip<\/code>\u65b9\u6cd5\u8df3\u8fc7\u6d41\u4e2d\u7684\u5143\u7d20\uff0c\u4e0a\u8ff0\u4f8b\u5b50\u8df3\u8fc7\u524d\u4e24\u4e2a\u5143\u7d20\uff0c\u6240\u4ee5\u6253\u5370\u7ed3\u679c\u4e3a2,3,4,5<\/code>\uff0cskip<\/code>\u7684\u53c2\u6570\u503c\u5fc5\u987b>=0<\/code>\uff0c\u5426\u5219\u5c06\u4f1a\u629b\u51fa\u5f02\u5e38<\/p>\nsorted<\/h4>\n
sorted \u65b9\u6cd5\u7528\u4e8e\u5bf9\u6d41\u8fdb\u884c\u6392\u5e8f\u3002\u4ee5\u4e0b\u4ee3\u7801\u7247\u6bb5\u4f7f\u7528 sorted \u65b9\u6cd5\u5bf9\u8f93\u51fa\u7684 10 \u4e2a\u968f\u673a\u6570\u8fdb\u884c\u6392\u5e8f\uff1a<\/p>\n
Random random = new Random();\r\nrandom.ints().limit(10).sorted().forEach(System.out::println);\r\n<\/code><\/pre>\n\u5143\u7d20\u5339\u914d<\/h3>\n
\u63d0\u4f9b\u4e86\u4e09\u79cd\u5339\u914d\u65b9\u5f0f<\/p>\n
\n- allMatch\u5339\u914d\u6240\u6709<\/li>\n<\/ul>\n
\u901a\u8fc7allMatch<\/code>\u65b9\u6cd5\u5b9e\u73b0<\/p>\nList<Integer> integerList = Arrays.asList(1, 2, 3, 4, 5);\r\nif (integerList.stream().allMatch(i -> i > 3)) {\r\n System.out.println(\"\u503c\u90fd\u5927\u4e8e3\");\r\n}\r\n<\/code><\/pre>\n\n- anyMatch\u5339\u914d\u5176\u4e2d\u4e00\u4e2a<\/li>\n<\/ul>\n
List<Integer> integerList = Arrays.asList(1, 2, 3, 4, 5);\r\nif (integerList.stream().anyMatch(i -> i > 3)) {\r\n System.out.println(\"\u5b58\u5728\u5927\u4e8e3\u7684\u503c\");\r\n}\r\n<\/code><\/pre>\n\u7b49\u4ef7\u4e8e<\/p>\n
List<Integer> integerList = Arrays.asList(1, 2, 3, 4, 5);\r\nfor (Integer integer : integerList) {\r\n if (integer>3){\r\n System.out.println(\"\u5b58\u5728\u5927\u4e8e3\u7684\u503c\");\r\n break;\r\n }\r\n}\r\n<\/code><\/pre>\n\u5b58\u5728\u5927\u4e8e3\u7684\u503c\u5219\u6253\u5370\uff0cjava8<\/code>\u4e2d\u901a\u8fc7anyMatch<\/code>\u65b9\u6cd5\u5b9e\u73b0\u8fd9\u4e2a\u529f\u80fd<\/p>\n\n- noneMatch\u5168\u90e8\u4e0d\u5339\u914d<\/li>\n<\/ul>\n
List<Integer> integerList = Arrays.asList(1, 2, 3, 4, 5);\r\nif (integerList.stream().noneMatch(i -> i>6)) {\r\n System.out.println(\"\u503c\u90fd\u5c0f\u4e8e6\");\r\n}\r\n<\/code><\/pre>\n\u901a\u8fc7noneMatch<\/code>\u65b9\u6cd5\u5b9e\u73b0<\/p>\n\u7ec8\u7aef\u64cd\u4f5c<\/h3>\n\u7edf\u8ba1\u6d41\u4e2d\u5143\u7d20\u4e2a\u6570<\/h4>\n\n- \u901a\u8fc7count<\/li>\n<\/ul>\n
\u901a\u8fc7\u4f7f\u7528count<\/code>\u65b9\u6cd5\u7edf\u8ba1\u51fa\u6d41\u4e2d\u5143\u7d20\u4e2a\u6570<\/p>\nList<Integer> integerList = Arrays.asList(1, 2, 3, 4, 5);\r\nlong count = integerList.stream().count();\r\nSystem.out.println(\"count:\"+count);\r\n<\/code><\/pre>\n\u7b49\u4ef7\u4e8e\u901a\u8fc7counting<\/code><\/p>\nList<Integer> integerList = Arrays.asList(1, 2, 3, 4, 5);\r\nLong counting = integerList.stream().collect(Collectors.counting());\r\nSystem.out.println(\"counting:\"+counting);\r\n<\/code><\/pre>\n\u67e5\u627e<\/h4>\n
\u63d0\u4f9b\u4e86\u4e24\u79cd\u67e5\u627e\u65b9\u5f0f<\/p>\n
\n- findFirst\u67e5\u627e\u7b2c\u4e00\u4e2a<\/li>\n<\/ul>\n
\u901a\u8fc7findFirst<\/code>\u65b9\u6cd5\u67e5\u627e\u5230\u7b2c\u4e00\u4e2a\u5927\u4e8e\u4e09\u7684\u5143\u7d20\u5e76\u6253\u5370<\/p>\nList<Integer> integerList = Arrays.asList(1, 2, 3, 4, 5);\r\nOptional<Integer> first = integerList.stream().filter(i -> i > 3).findFirst();\r\nSystem.out.println(\"first:\"+first.get());\r\n<\/code><\/pre>\n\n- findAny\u968f\u673a\u67e5\u627e\u4e00\u4e2a<\/li>\n<\/ul>\n
List<Integer> integerList = Arrays.asList(1, 2, 3, 4, 5);\r\nOptional<Integer> any = integerList.stream().filter(i -> i > 3).findAny();\r\nSystem.out.println(\"any:\"+any.get());\r\n<\/code><\/pre>\n\u901a\u8fc7findAny<\/code>\u65b9\u6cd5\u67e5\u627e\u5230\u5176\u4e2d\u4e00\u4e2a\u5927\u4e8e\u4e09\u7684\u5143\u7d20\u5e76\u6253\u5370\uff0c\u56e0\u4e3a\u5185\u90e8\u8fdb\u884c\u4f18\u5316\u7684\u539f\u56e0\uff0c\u5f53\u627e\u5230\u7b2c\u4e00\u4e2a\u6ee1\u8db3\u5927\u4e8e\u4e09\u7684\u5143\u7d20\u65f6\u5c31\u7ed3\u675f\uff0c\u8be5\u65b9\u6cd5\u7ed3\u679c\u548cfindFirst<\/code>\u65b9\u6cd5\u7ed3\u679c\u4e00\u6837\u3002\u63d0\u4f9bfindAny<\/code>\u65b9\u6cd5\u662f\u4e3a\u4e86\u66f4\u597d\u7684\u5229\u7528\u5e76\u884c\u6d41\uff0cfindFirst<\/code>\u65b9\u6cd5\u5728\u5e76\u884c\u4e0a\u9650\u5236\u66f4\u591a<\/p>\nreduce\u5c06\u6d41\u4e2d\u7684\u5143\u7d20\u7ec4\u5408\u8d77\u6765<\/h3>\n
\u5047\u8bbe\u6211\u4eec\u5bf9\u4e00\u4e2a\u96c6\u5408\u4e2d\u7684\u503c\u8fdb\u884c\u6c42\u548c<\/p>\n
\n- jdk8\u4e4b\u524d<\/li>\n<\/ul>\n
List<Integer> integerList = Arrays.asList(1, 2, 3, 4, 5);\r\nint sum = 0;\r\nfor (Integer integer : integerList) {\r\n sum += integer;\r\n}\r\nSystem.out.println(\"sum:\"+sum);\r\n<\/code><\/pre>\n\n- jdk8\u4e4b\u540e\u901a\u8fc7reduce\u8fdb\u884c\u5904\u7406<\/li>\n<\/ul>\n
List<Integer> integerList = Arrays.asList(1, 2, 3, 4, 5);\r\nint sum = integerList.stream().reduce(0,(a,b) -> a+b);\r\nSystem.out.println(\"sum:\"+sum);\r\n<\/code><\/pre>\n\u4e00\u884c\u5c31\u53ef\u4ee5\u5b8c\u6210\uff0c\u8fd8\u53ef\u4ee5\u4f7f\u7528\u65b9\u6cd5\u5f15\u7528\u7b80\u5199\u6210:<\/p>\n
int sum = integerList.stream().reduce(0, Integer::sum);\r\n<\/code><\/pre>\nreduce<\/code>\u63a5\u53d7\u4e24\u4e2a\u53c2\u6570\uff0c\u4e00\u4e2a\u521d\u59cb\u503c\u8fd9\u91cc\u662f0<\/code>\uff0c\u4e00\u4e2aBinaryOperator<T> accumulator<\/code> \u6765\u5c06\u4e24\u4e2a\u5143\u7d20\u7ed3\u5408\u8d77\u6765\u4ea7\u751f\u4e00\u4e2a\u65b0\u503c\uff0c \u53e6\u5916reduce<\/code>\u65b9\u6cd5\u8fd8\u6709\u4e00\u4e2a\u6ca1\u6709\u521d\u59cb\u5316\u503c\u7684\u91cd\u8f7d\u65b9\u6cd5<\/p>\n\u83b7\u53d6\u6d41\u4e2d\u6700\u5c0f\u6700\u5927\u503c<\/h3>\n\n- \u901a\u8fc7min\/max\u83b7\u53d6\u6700\u5c0f\u6700\u5927\u503c<\/li>\n<\/ul>\n
List<Integer> integerList = Arrays.asList(1, 2, 3, 4, 5,-1,-100);\r\nintegerList.stream().min((e1,e2) -> e1.compareTo(e2)).ifPresent(i -> System.out.println(\"i:\"+i));\r\n<\/code><\/pre>\n\u540c\u7406max\u662f\uff1a<\/p>\n
List<Integer> integerList = Arrays.asList(1, 2, 3, 4, 5,-1,-100);\r\nintegerList.stream().max((e1,e2) -> e1.compareTo(e2)).ifPresent(i -> System.out.println(\"i:\"+i));\r\n<\/code><\/pre>\n <\/p>\n","protected":false},"excerpt":{"rendered":"
\u4ec0\u4e48\u662f Stream\uff1f Stream\uff08\u6d41\uff09\u662f\u4e00\u4e2a\u6765\u81ea\u6570\u636e\u6e90\u7684\u5143\u7d20\u961f\u5217\u5e76\u652f\u6301\u805a\u5408\u64cd\u4f5c \u5143\u7d20\u662f\u7279\u5b9a\u7c7b\u578b\u7684\u5bf9\u8c61\uff0c\u5f62\u6210 […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[292],"tags":[129,316,317],"class_list":["post-1761","post","type-post","status-publish","format-standard","hentry","category-java","tag-java","tag-jdk8","tag-stream"],"_links":{"self":[{"href":"https:\/\/199604.com\/wp-json\/wp\/v2\/posts\/1761","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/199604.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/199604.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/199604.com\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/199604.com\/wp-json\/wp\/v2\/comments?post=1761"}],"version-history":[{"count":1,"href":"https:\/\/199604.com\/wp-json\/wp\/v2\/posts\/1761\/revisions"}],"predecessor-version":[{"id":1762,"href":"https:\/\/199604.com\/wp-json\/wp\/v2\/posts\/1761\/revisions\/1762"}],"wp:attachment":[{"href":"https:\/\/199604.com\/wp-json\/wp\/v2\/media?parent=1761"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/199604.com\/wp-json\/wp\/v2\/categories?post=1761"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/199604.com\/wp-json\/wp\/v2\/tags?post=1761"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}