{"id":202915,"date":"2025-05-22T09:19:36","date_gmt":"2025-05-22T01:19:36","guid":{"rendered":"https:\/\/server.hk\/cnblog\/202915\/"},"modified":"2025-05-22T09:19:36","modified_gmt":"2025-05-22T01:19:36","slug":"%e5%a6%82%e4%bd%95%e5%b0%86lambda%e8%a1%a8%e8%be%be%e5%bc%8f%e4%b8%8ejava-stream-api%e7%bb%93%e5%90%88%e4%bd%bf%e7%94%a8%ef%bc%9f","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/202915\/","title":{"rendered":"\u5982\u4f55\u5c06lambda\u8868\u8fbe\u5f0f\u4e0eJava Stream API\u7ed3\u5408\u4f7f\u7528\uff1f"},"content":{"rendered":"

<\/b> <\/p>\n

\u5982\u4f55\u5c06lambda\u8868\u8fbe\u5f0f\u4e0eJava Stream API\u7ed3\u5408\u4f7f\u7528\uff1f<\/h1>\n

\u6700\u8fd1\u53d1\u73b0\u4e0d\u5c11\u5c0f\u4f19\u4f34\u90fd\u5bf9\u6587\u7ae0<\/span>\u5f88\u611f\u5174\u8da3\uff0c\u6240\u4ee5\u4eca\u5929\u7ee7\u7eed\u7ed9\u5927\u5bb6\u4ecb\u7ecd\u6587\u7ae0<\/span>\u76f8\u5173\u7684\u77e5\u8bc6\uff0c\u672c\u6587\u300a\u5982\u4f55\u5c06lambda\u8868\u8fbe\u5f0f\u4e0eJava Stream API\u7ed3\u5408\u4f7f\u7528\uff1f\u300b<\/span>\u4e3b\u8981\u5185\u5bb9\u6d89\u53ca\u5230<\/span>\u7b49\u7b49\u77e5\u8bc6\u70b9\uff0c\u5e0c\u671b\u80fd\u5e2e\u5230\u4f60\uff01\u5f53\u7136\u5982\u679c\u9605\u8bfb\u672c\u6587\u65f6\u5b58\u5728\u4e0d\u540c\u60f3\u6cd5\uff0c\u53ef\u4ee5\u5728\u8bc4\u8bba\u4e2d\u8868\u8fbe\uff0c\u4f46\u662f\u8bf7\u52ff\u4f7f\u7528\u8fc7\u6fc0\u7684\u63aa\u8f9e~<\/p>\n

\u5982\u4f55\u5c06 lambda \u8868\u8fbe\u5f0f\u4e0e Java Stream API \u7ed3\u5408\u4f7f\u7528\uff1flambda \u8868\u8fbe\u5f0f\u53ef\u4ee5\u4f5c\u4e3a Stream API \u65b9\u6cd5\u7684\u53c2\u6570\uff0c\u7528\u4e8e\u5bf9\u96c6\u5408\u5143\u7d20\u6267\u884c\u64cd\u4f5c\u3002\u7b5b\u9009\uff1a\u4f7f\u7528 lambda \u8868\u8fbe\u5f0f\u4ece\u5217\u8868\u4e2d\u7b5b\u9009\u5143\u7d20\uff0c\u4f8b\u5982\u7b5b\u9009\u51fa\u5076\u6570\u3002\u6620\u5c04\uff1a\u4f7f\u7528 lambda \u8868\u8fbe\u5f0f\u5c06\u6bcf\u4e2a\u5143\u7d20\u6620\u5c04\u5230\u53e6\u4e00\u4e2a\u503c\uff0c\u4f8b\u5982\u5c06\u540d\u79f0\u8f6c\u6362\u4e3a\u5927\u5199\u3002\u89c4\u7ea6\uff1a\u4f7f\u7528 lambda \u8868\u8fbe\u5f0f\u5bf9\u6d41\u4e2d\u7684\u5143\u7d20\u8fdb\u884c\u89c4\u7ea6\uff0c\u4f8b\u5982\u6c42\u548c\u6216\u67e5\u627e\u6700\u5927\u503c\u3002\u5b9e\u6218\u6848\u4f8b\uff1a\u4f7f\u7528 lambda \u8868\u8fbe\u5f0f\u548c Stream API \u4ece\u6587\u4ef6\u4e2d\u63d0\u53d6\u5355\u8bcd\uff0c\u7b5b\u9009\u51fa\u957f\u5ea6\u5927\u4e8e 6 \u7684\u5355\u8bcd\u3002<\/p>\n

<\/p>\n

\u5982\u4f55\u5c06 lambda \u8868\u8fbe\u5f0f\u4e0e Java Stream API \u7ed3\u5408\u4f7f\u7528<\/strong><\/p>\n

\u5f15\u8a00<\/strong><\/p>\n

Stream API \u662f Java 8 \u4e2d\u5f15\u5165\u7684\u4e00\u7ec4\u529f\u80fd\u5f3a\u5927\u7684\u5de5\u5177\uff0c\u7528\u4e8e\u5904\u7406\u96c6\u5408\u5143\u7d20\u3002Lambda \u8868\u8fbe\u5f0f\u662f\u7b80\u5316\u4ee3\u7801\u5e76\u4f7f\u5176\u66f4\u6613\u8bfb\u7684\u533f\u540d\u51fd\u6570\u3002\u7ed3\u5408\u4f7f\u7528\u8fd9\u4e24\u79cd\u6280\u672f\uff0c\u60a8\u53ef\u4ee5\u7f16\u5199\u7b80\u6d01\u4e14\u53ef\u8bfb\u7684\u4ee3\u7801\u6765\u5904\u7406\u548c\u64cd\u4f5c\u96c6\u5408\u3002<\/p>\n

lambda \u8868\u8fbe\u5f0f\u4e0e Stream API<\/strong><\/p>\n

lambda \u8868\u8fbe\u5f0f\u53ef\u4ee5\u4f20\u9012\u7ed9 Stream API \u65b9\u6cd5\uff0c\u4f5c\u4e3a\u6267\u884c\u7279\u5b9a\u64cd\u4f5c\u7684\u51fd\u6570\u3002\u8fd9\u4f7f\u60a8\u53ef\u4ee5\u5bf9\u96c6\u5408\u4e2d\u7684\u5143\u7d20\u8fdb\u884c\u7b5b\u9009\u3001\u6620\u5c04\u548c\u89c4\u7ea6\u3002<\/p>\n

\u7b5b\u9009<\/strong><\/p>\n

\u4ee5\u4e0b\u4ee3\u7801\u663e\u793a\u4e86\u5982\u4f55\u4f7f\u7528 lambda \u8868\u8fbe\u5f0f\u4ece\u5217\u8868\u4e2d\u7b5b\u9009\u5076\u6570\uff1a<\/p>\n

List<Integer> numbers = Arrays.asList(1, 2, 3, 4, 5, 6);\nList<Integer> evenNumbers = numbers.stream()\n                                    .filter(n -> n % 2 == 0)\n                                    .toList();<\/pre>\n
\u6620\u5c04<\/strong><\/p>\n
\u60a8\u53ef\u4ee5\u4f7f\u7528 lambda \u8868\u8fbe\u5f0f\u5c06\u6bcf\u4e2a\u5143\u7d20\u6620\u5c04\u5230\u53e6\u4e00\u4e2a\u503c\uff1a<\/p>\n
List<String> names = Arrays.asList(\"Alice\", \"Bob\", \"Charlie\");\nList<String> upperCaseNames = names.stream()\n                                   .map(String::toUpperCase)\n                                   .toList();<\/pre>\n
\u89c4\u7ea6<\/strong><\/p>\n
lambda \u8868\u8fbe\u5f0f\u4e5f\u53ef\u7528\u4e8e\u89c4\u7ea6\u6d41\u4e2d\u7684\u5143\u7d20\uff0c\u4f8b\u5982\u6c42\u548c\u6216\u67e5\u627e\u6700\u5927\u503c\uff1a<\/p>\n
int sum = numbers.stream()\n                .reduce(0, (a, b) -> a + b);<\/pre>\n
\u5b9e\u6218\u6848\u4f8b<\/strong><\/p>\n
\u8ba9\u6211\u4eec\u4e3e\u4e00\u4e2a\u5b9e\u6218\u6848\u4f8b\uff0c\u6f14\u793a\u5982\u4f55\u4f7f\u7528 lambda \u8868\u8fbe\u5f0f\u548c Stream API \u4ece\u6587\u4ef6\u4e2d\u63d0\u53d6\u5355\u8bcd\uff1a<\/p>\n
import java.io.IOException;\nimport java.nio.file.Files;\nimport java.nio.file.Paths;\nimport java.util.Arrays;\nimport java.util.List;\n\npublic class WordExtractor {\n\n    public static void main(String[] args) {\n        \/\/ \u4ece\u6587\u4ef6\u4e2d\u8bfb\u53d6\u6587\u672c\n        String text = null;\n        try {\n            text = new String(Files.readAllBytes(Paths.get(\"input.txt\")));\n        } catch (IOException e) {\n            e.printStackTrace();\n        }\n\n        \/\/ \u5c06\u6587\u672c\u62c6\u5206\u4e3a\u5355\u8bcd\n        List<String> words = Arrays.asList(text.split(\"\\\\s+\"));\n\n        \/\/ \u7b5b\u9009\u5e76\u6253\u5370\u957f\u5ea6\u5927\u4e8e 6 \u7684\u5355\u8bcd\n        words.stream()\n            .filter(word -> word.length() > 6)\n            .forEach(System.out::println);\n    }\n}<\/pre>\n
\u7ed3\u8bba<\/strong><\/p>\n
\u4f7f\u7528 lambda \u8868\u8fbe\u5f0f\u548c Stream API \u63d0\u4f9b\u4e86\u4e00\u79cd\u7b80\u6d01\u4e14\u53ef\u8bfb\u7684\u65b9\u5f0f\u6765\u5904\u7406\u548c\u64cd\u4f5c\u96c6\u5408\u3002\u901a\u8fc7\u4f7f\u7528\u8fd9\u4e24\u79cd\u6280\u672f\uff0c\u60a8\u53ef\u4ee5\u5feb\u901f\u9ad8\u6548\u5730\u5bf9\u6570\u636e\u8fdb\u884c\u7b5b\u9009\u3001\u6620\u5c04\u548c\u89c4\u7ea6\u3002<\/p>\n
\u4ee5\u4e0a\u5c31\u662f\u672c\u6587\u7684\u5168\u90e8\u5185\u5bb9\u4e86\uff0c\u662f\u5426\u6709\u987a\u5229\u5e2e\u52a9\u4f60\u89e3\u51b3\u95ee\u9898\uff1f\u82e5\u662f\u80fd\u7ed9\u4f60\u5e26\u6765\u5b66\u4e60\u4e0a\u7684\u5e2e\u52a9\uff0c\u8bf7\u5927\u5bb6\u591a\u591a\u652f\u6301\uff01\u66f4\u591a\u5173\u4e8e\u6587\u7ae0\u7684\u76f8\u5173\u77e5\u8bc6\uff0c\u4e5f\u53ef\u5173\u6ce8\u516c\u4f17\u53f7\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
\u5982\u4f55\u5c06lambda\u8868\u8fbe\u5f0f\u4e0eJav...<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4925],"tags":[],"class_list":["post-202915","post","type-post","status-publish","format-standard","hentry","category-4925"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/202915","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/comments?post=202915"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/202915\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=202915"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=202915"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=202915"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}