{"id":202516,"date":"2025-05-22T08:12:10","date_gmt":"2025-05-22T00:12:10","guid":{"rendered":"https:\/\/server.hk\/cnblog\/202516\/"},"modified":"2025-05-22T08:12:10","modified_gmt":"2025-05-22T00:12:10","slug":"java%e5%87%bd%e6%95%b0%e5%bc%8f%e7%bc%96%e7%a8%8b%e5%9c%a8%e6%95%b0%e6%8d%ae%e5%a4%84%e7%90%86%e4%b8%ad%e5%a6%82%e4%bd%95%e6%8f%90%e5%8d%87%e6%95%88%e7%8e%87%ef%bc%9f","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/202516\/","title":{"rendered":"Java\u51fd\u6570\u5f0f\u7f16\u7a0b\u5728\u6570\u636e\u5904\u7406\u4e2d\u5982\u4f55\u63d0\u5347\u6548\u7387\uff1f"},"content":{"rendered":"<p><b><\/b>     <\/p>\n<h1>Java\u51fd\u6570\u5f0f\u7f16\u7a0b\u5728\u6570\u636e\u5904\u7406\u4e2d\u5982\u4f55\u63d0\u5347\u6548\u7387\uff1f<\/h1>\n<p>\u672c\u7bc7\u6587\u7ae0\u5411\u5927\u5bb6\u4ecb\u7ecd\u300aJava\u51fd\u6570\u5f0f\u7f16\u7a0b\u5728\u6570\u636e\u5904\u7406\u4e2d\u5982\u4f55\u63d0\u5347\u6548\u7387\uff1f\u300b\uff0c\u4e3b\u8981\u5305\u62ec\uff0c\u5177\u6709\u4e00\u5b9a\u7684\u53c2\u8003\u4ef7\u503c\uff0c\u9700\u8981\u7684\u670b\u53cb\u53ef\u4ee5\u53c2\u8003\u4e00\u4e0b\u3002<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/www.17golang.com\/uploads\/20241026\/1729913310671c61de7aed4.jpg\" class=\"aligncenter\"><\/p>\n<p><strong>Java\u51fd\u6570\u5f0f\u7f16\u7a0b\u5728\u6570\u636e\u5904\u7406\u4e2d\u63d0\u5347\u6548\u7387<\/strong><\/p>\n<p><strong>\u524d\u8a00<\/strong><\/p>\n<p>Java 8 \u5f15\u5165\u4e86\u51fd\u6570\u5f0f\u7f16\u7a0b\u8303\u5f0f\uff0c\u8fd9\u662f\u4e00\u79cd\u5f3a\u5927\u7684\u5de5\u5177\uff0c\u53ef\u4ee5\u63d0\u9ad8\u6570\u636e\u5904\u7406\u6548\u7387\u3002\u672c\u6587\u5c06\u63a2\u7a76\u4ee5\u4e0b\u5185\u5bb9\uff1a<\/p>\n<ul>\n<li>Java \u51fd\u6570\u5f0f\u7f16\u7a0b\u7684\u6982\u8ff0<\/li>\n<li>\u6d41\u5f0f\u5904\u7406\u548c Lambda \u8868\u8fbe\u5f0f<\/li>\n<li>\u5b9e\u6218\u6848\u4f8b\uff1a\u4f18\u5316\u5927\u6570\u636e\u5904\u7406<\/li>\n<\/ul>\n<p><strong>Java \u51fd\u6570\u5f0f\u7f16\u7a0b\u6982\u8ff0<\/strong><\/p>\n<p>\u51fd\u6570\u5f0f\u7f16\u7a0b\u57fa\u4e8e\u4ee5\u4e0b\u539f\u5219\uff1a<\/p>\n<ul>\n<li>\u51fd\u6570\u662f\u4e0d\u5e26\u526f\u4f5c\u7528\u7684\u7eaf\u51fd\u6570<\/li>\n<li>\u51fd\u6570\u53ef\u4ee5\u4f5c\u4e3a\u53e6\u4e00\u4e2a\u51fd\u6570\u7684\u53c2\u6570<\/li>\n<li>\u51fd\u6570\u53ef\u4ee5\u8fd4\u56de\u5176\u4ed6\u51fd\u6570<\/li>\n<\/ul>\n<p>Java 8 \u63d0\u4f9b\u4e86\u591a\u79cd\u51fd\u6570\u5f0f\u63a5\u53e3\u548c\u65b9\u6cd5\uff0c\u5982 <code>stream()<\/code>\u3001<code>map()<\/code>\u3001<code>filter()<\/code> \u548c <code>reduce()<\/code>\uff0c\u8fd9\u4e9b\u63a5\u53e3\u548c\u65b9\u6cd5\u4f7f\u6211\u4eec\u80fd\u591f\u4ee5\u58f0\u660e\u5f0f\u65b9\u5f0f\u5904\u7406\u6570\u636e\uff0c\u63d0\u9ad8\u4ee3\u7801\u7684\u53ef\u8bfb\u6027\u548c\u53ef\u7ef4\u62a4\u6027\u3002<\/p>\n<p><strong>\u6d41\u5f0f\u5904\u7406\u548c Lambda \u8868\u8fbe\u5f0f<\/strong><\/p>\n<p>\u6d41\u5f0f\u5904\u7406\u6d89\u53ca\u4f7f\u7528 <code>Stream<\/code> \u5bf9\u8c61\u6765\u8868\u793a\u4e00\u7cfb\u5217\u5143\u7d20\u3002\u6d41\u5f0f\u5904\u7406\u975e\u5e38\u9002\u5408\u5e76\u884c\u5904\u7406\u5927\u6570\u636e\u96c6\u5408\uff0c\u56e0\u4e3a\u5b83\u53ef\u4ee5\u5c06\u6570\u636e\u5904\u7406\u59d4\u6258\u7ed9\u5e95\u5c42\u6846\u67b6\u3002<\/p>\n<p>Lambda \u8868\u8fbe\u5f0f\u662f\u533f\u540d\u51fd\u6570\uff0c\u53ef\u4ee5\u4f5c\u4e3a\u53c2\u6570\u4f20\u9012\u7ed9\u51fd\u6570\u6216\u5b58\u50a8\u5728\u53d8\u91cf\u4e2d\u3002\u5b83\u4eec\u5141\u8bb8\u6211\u4eec\u5b9a\u4e49\u7b80\u77ed\u3001\u6e05\u6670\u4e14\u53ef\u91cd\u7528\u7684\u4ee3\u7801\u5757\u3002<\/p>\n<p><strong>\u5b9e\u6218\u6848\u4f8b\uff1a\u4f18\u5316\u5927\u6570\u636e\u5904\u7406<\/strong><\/p>\n<p>\u8003\u8651\u4ee5\u4e0b\u573a\u666f\uff1a\u6211\u4eec\u6709\u4e00\u4e2a\u5305\u542b\u6570\u767e\u4e07\u4e2a\u65e5\u5fd7\u8bb0\u5f55\u7684\u5927\u6570\u636e\u65e5\u5fd7\u6587\u4ef6\uff0c\u6211\u4eec\u9700\u8981\uff1a<\/p>\n<ul>\n<li>\u8fc7\u6ee4\u5305\u542b\u9519\u8bef\u6d88\u606f\u7684\u8bb0\u5f55<\/li>\n<li>\u4ece\u6bcf\u4e2a\u8bb0\u5f55\u4e2d\u63d0\u53d6\u9519\u8bef\u4ee3\u7801<\/li>\n<li>\u7edf\u8ba1\u6bcf\u79cd\u9519\u8bef\u4ee3\u7801\u7684\u51fa\u73b0\u6b21\u6570<\/li>\n<\/ul>\n<p>\u4f7f\u7528\u4f20\u7edf\u7684\u547d\u4ee4\u5f0f\u7f16\u7a0b\u65b9\u6cd5\uff0c\u8fd9\u4e2a\u8fc7\u7a0b\u53ef\u80fd\u4f1a\u5f88\u8017\u65f6\u3002\u7136\u800c\uff0c\u4f7f\u7528 Java \u51fd\u6570\u5f0f\u7f16\u7a0b\uff0c\u6211\u4eec\u53ef\u4ee5\u5229\u7528\u4ee5\u4e0b\u6280\u672f\u4f18\u5316\u6b64\u8fc7\u7a0b\uff1a<\/p>\n<pre>\/\/ \u83b7\u53d6\u65e5\u5fd7\u6587\u4ef6\u7684\u884c\nStream&lt;String&gt; lines = Files.lines(Paths.get(\"logfile.txt\"));\n\n\/\/ \u8fc7\u6ee4\u9519\u8bef\u6d88\u606f\u5e76\u63d0\u53d6\u9519\u8bef\u4ee3\u7801\nStream&lt;String&gt; errorCodes = lines\n    .filter(line -&gt; line.contains(\"ERROR\"))\n    .map(line -&gt; line.substring(line.indexOf(\"ERROR\") + 6, line.indexOf(':', line.indexOf(\"ERROR\") + 6)));\n\n\/\/ \u7edf\u8ba1\u6bcf\u79cd\u9519\u8bef\u4ee3\u7801\u7684\u51fa\u73b0\u6b21\u6570\nMap&lt;String, Long&gt; errorCounts = errorCodes\n    .collect(Collectors.groupingBy(Function.identity(), Collectors.counting()));\n\n\/\/ \u6253\u5370\u7ed3\u679c\nerrorCounts.forEach((code, count) -&gt; System.out.println(code + \": \" + count));<\/pre>\n<p>\u5728\u8fd9\u79cd\u4f18\u5316\u540e\u7684\u89e3\u51b3\u65b9\u6848\u4e2d\uff1a<\/p>\n<ul>\n<li>\u6d41\u5f0f\u5904\u7406\u4f7f\u6211\u4eec\u80fd\u591f\u4ee5\u5e76\u884c\u65b9\u5f0f\u5904\u7406\u65e5\u5fd7\u8bb0\u5f55<\/li>\n<li>Lambda \u8868\u8fbe\u5f0f\u5141\u8bb8\u6211\u4eec\u8f7b\u677e\u5b9a\u4e49\u8fc7\u6ee4\u548c\u63d0\u53d6\u903b\u8f91<\/li>\n<li><code>Collectors<\/code> \u7c7b\u63d0\u4f9b\u4e86\u9ad8\u6548\u7684\u65b9\u6cd5\u6765\u5bf9\u6570\u636e\u8fdb\u884c\u5206\u7ec4\u548c\u7edf\u8ba1<\/li>\n<\/ul>\n<p>\u901a\u8fc7\u4f7f\u7528\u8fd9\u4e9b\u6280\u672f\uff0c\u6211\u4eec\u663e\u7740\u63d0\u9ad8\u4e86\u5904\u7406\u5927\u6570\u636e\u65e5\u5fd7\u6587\u4ef6\u7684\u901f\u5ea6\u548c\u6548\u7387\u3002<\/p>\n<p>\u7ec8\u4e8e\u4ecb\u7ecd\u5b8c\u5566\uff01\u5c0f\u4f19\u4f34\u4eec\uff0c\u8fd9\u7bc7\u5173\u4e8e\u300aJava\u51fd\u6570\u5f0f\u7f16\u7a0b\u5728\u6570\u636e\u5904\u7406\u4e2d\u5982\u4f55\u63d0\u5347\u6548\u7387\uff1f\u300b\u7684\u4ecb\u7ecd\u5e94\u8be5\u8ba9\u4f60\u6536\u83b7\u591a\u591a\u4e86\u5427\uff01\u6b22\u8fce\u5927\u5bb6\u6536\u85cf\u6216\u5206\u4eab\u7ed9\u66f4\u591a\u9700\u8981\u5b66\u4e60\u7684\u670b\u53cb\u5427~\u516c\u4f17\u53f7\u4e5f\u4f1a\u53d1\u5e03\u6587\u7ae0\u76f8\u5173\u77e5\u8bc6\uff0c\u5feb\u6765\u5173\u6ce8\u5427\uff01<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Java\u51fd\u6570\u5f0f\u7f16\u7a0b\u5728\u6570\u636e\u5904\u7406\u4e2d\u5982&#46;&#46;&#46;<\/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-202516","post","type-post","status-publish","format-standard","hentry","category-4925"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/202516","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=202516"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/202516\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=202516"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=202516"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=202516"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}