{"id":205,"date":"2023-12-01T11:29:19","date_gmt":"2023-12-01T03:29:19","guid":{"rendered":"https:\/\/www.coffecat.cn\/?p=205"},"modified":"2024-08-27T12:39:04","modified_gmt":"2024-08-27T04:39:04","slug":"java8-stream%e6%b5%81%e4%b9%8bmap%e9%9b%86%e5%90%88%e9%94%ae%e5%80%bc%e5%af%b9%e6%8d%a2","status":"publish","type":"post","link":"https:\/\/www.coffecat.cn\/index.php\/2023\/12\/01\/java8-stream%e6%b5%81%e4%b9%8bmap%e9%9b%86%e5%90%88%e9%94%ae%e5%80%bc%e5%af%b9%e6%8d%a2\/","title":{"rendered":"Java8 Stream\u6d41\u4e4bmap\u96c6\u5408\u952e\u503c\u5bf9\u6362"},"content":{"rendered":"\n<p>\u76ee\u7684\uff1a\u56e0\u4e3a\u5728\u5f00\u53d1\u8fc7\u7a0b\u4e2d\u4f1a\u4f7f\u7528\u5230\u5b57\u5178\uff0c\u901a\u8fc7\u5b9e\u4f53\u4e2d\u7684\u5b57\u5178\u5b57\u6bb5\u505a\u5bf9\u7167\uff0c\u4e4b\u524d\u9879\u76ee\u4e2d\u5927\u591a\u6570\u662f\u901a\u8fc7\u6ce8\u89e3\u53bb\u505a\u5b57\u5178\u5bf9\u7167\u7684\uff0c\u53ea\u9700\u8981\u52a0\u5728\u5b9e\u4f53\u4e0a\u5c31\u53ef\u4ee5\u5b9e\u73b0\u5bf9\u7167\u5b57\u6bb5\u586b\u5145\u3002\u4f46\u73b0\u5728\u4f7f\u7528\u7684\u662f\u679a\u4e3e\u6216\u8005\u662f\u901a\u8fc7\u63a5\u53e3\u83b7\u53d6\u7684\u5b57\u5178\u96c6\u5408\uff0c\u57fa\u672c\u4e0a\u90fd\u662f\u901a\u8fc7\u952e\u627e\u503c\u7684\uff0c\u5bf9\u4e8e\u4e00\u4e9b\u7279\u6b8a\u573a\u666f\uff0c\u6bd4\u5982\u5728\u5bfc\u5165excel\u65f6\uff08\u573a\u666f\u4e3a\u9879\u76ee\u4e2d\u7edf\u4e00\u4f7f\u7528<em>InputStream<\/em>\u7684\u65b9\u5f0f\u8bfb\u53d6\u6570\u636e\uff09\u6709\u4e9b\u4e0b\u62c9\u6846\u91cc\u7684\u503c\u8bfb\u53d6\u5230\u90fd\u662f\u503c\uff0c\u8fd9\u65f6\u5c31\u9700\u8981\u901a\u8fc7\u5b57\u5178\u7684\u503c\u53bb\u627e\u952e\u4e86\u3002<\/p>\n\n\n\n<p>\u5982\u679c\u662f\u8fd9\u6837\u7684\u8bdd\u53ef\u4ee5\u5c06\u5b57\u5178\u91cc\u7684\u503c\u904d\u5386\u7136\u540e\u5bf9\u8c03\u952e\u503c\uff0c\u8fd9\u6837\u5c31\u53ef\u4ee5\u901a\u8fc7\u65b0\u7ec4\u88c5\u7684\u952e\u53bb\u627e\u503c\u4e86\uff0c\u4f46\u5176\u5b9e\u5e76\u4e0d\u4f18\u96c5\uff0c\u4e4b\u524d\u5728\u9879\u76ee\u4e2d\u6709\u770b\u5230\u8fc7\u522b\u7684\u540c\u4e8b\u5199\u8fd9\u6837\u7684\u952e\u503c\u5bf9\u6362\u7684\u4ee3\u7801\u4f46\u662f\u6ca1\u60f3\u5230\u4f7f\u7528\u573a\u666f\uff0c\u540e\u6765\u505aexcel\u5bfc\u5165\u7684\u65f6\u5019\u624d\u60f3\u8d77\u6765\u8fd9\u4e2a\u4e8b\uff0c\u4e8e\u662f\u5c31\u501f\u9274\u4e86\u4e00\u4e0b\u3002<\/p>\n\n\n\n<div class=\"wp-block-kevinbatdorf-code-block-pro\" data-code-block-pro-font-family=\"Code-Pro-JetBrains-Mono\" style=\"font-size:.875rem;font-family:Code-Pro-JetBrains-Mono,ui-monospace,SFMono-Regular,Menlo,Monaco,Consolas,monospace;line-height:1.25rem;--cbp-tab-width:2;tab-size:var(--cbp-tab-width, 2)\"><span style=\"display:block;padding:16px 0 0 16px;margin-bottom:-1px;width:100%;text-align:left;background-color:#2e3440ff\"><svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"54\" height=\"14\" viewBox=\"0 0 54 14\"><g fill=\"none\" fill-rule=\"evenodd\" transform=\"translate(1 1)\"><circle cx=\"6\" cy=\"6\" r=\"6\" fill=\"#FF5F56\" stroke=\"#E0443E\" stroke-width=\".5\"><\/circle><circle cx=\"26\" cy=\"6\" r=\"6\" fill=\"#FFBD2E\" stroke=\"#DEA123\" stroke-width=\".5\"><\/circle><circle cx=\"46\" cy=\"6\" r=\"6\" fill=\"#27C93F\" stroke=\"#1AAB29\" stroke-width=\".5\"><\/circle><\/g><\/svg><\/span><span role=\"button\" tabindex=\"0\" data-code=\"map.entrySet().stream()\n                .collect(Collectors.toMap(Map.Entry::getValue, Map.Entry::getKey));\" style=\"color:#d8dee9ff;display:none\" aria-label=\"Copy\" class=\"code-block-pro-copy-button\"><svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" style=\"width:24px;height:24px\" fill=\"none\" viewBox=\"0 0 24 24\" stroke=\"currentColor\" stroke-width=\"2\"><path class=\"with-check\" stroke-linecap=\"round\" stroke-linejoin=\"round\" d=\"M9 5H7a2 2 0 00-2 2v12a2 2 0 002 2h10a2 2 0 002-2V7a2 2 0 00-2-2h-2M9 5a2 2 0 002 2h2a2 2 0 002-2M9 5a2 2 0 012-2h2a2 2 0 012 2m-6 9l2 2 4-4\"><\/path><path class=\"without-check\" stroke-linecap=\"round\" stroke-linejoin=\"round\" d=\"M9 5H7a2 2 0 00-2 2v12a2 2 0 002 2h10a2 2 0 002-2V7a2 2 0 00-2-2h-2M9 5a2 2 0 002 2h2a2 2 0 002-2M9 5a2 2 0 012-2h2a2 2 0 012 2\"><\/path><\/svg><\/span><pre class=\"shiki nord\" style=\"background-color: #2e3440ff\" tabindex=\"0\"><code><span class=\"line\"><span style=\"color: #D8DEE9\">map<\/span><span style=\"color: #ECEFF4\">.<\/span><span style=\"color: #88C0D0\">entrySet<\/span><span style=\"color: #ECEFF4\">().<\/span><span style=\"color: #88C0D0\">stream<\/span><span style=\"color: #ECEFF4\">()<\/span><\/span>\n<span class=\"line\"><span style=\"color: #D8DEE9FF\">                <\/span><span style=\"color: #ECEFF4\">.<\/span><span style=\"color: #88C0D0\">collect<\/span><span style=\"color: #ECEFF4\">(<\/span><span style=\"color: #D8DEE9\">Collectors<\/span><span style=\"color: #ECEFF4\">.<\/span><span style=\"color: #88C0D0\">toMap<\/span><span style=\"color: #ECEFF4\">(<\/span><span style=\"color: #D8DEE9\">Map<\/span><span style=\"color: #ECEFF4\">.<\/span><span style=\"color: #D8DEE9\">Entry<\/span><span style=\"color: #81A1C1\">::<\/span><span style=\"color: #D8DEE9FF\">getValue<\/span><span style=\"color: #ECEFF4\">,<\/span><span style=\"color: #D8DEE9FF\"> <\/span><span style=\"color: #D8DEE9\">Map<\/span><span style=\"color: #ECEFF4\">.<\/span><span style=\"color: #D8DEE9\">Entry<\/span><span style=\"color: #81A1C1\">::<\/span><span style=\"color: #D8DEE9FF\">getKey<\/span><span style=\"color: #ECEFF4\">))<\/span><span style=\"color: #81A1C1\">;<\/span><\/span><\/code><\/pre><\/div>\n\n\n\n<p>\u901a\u8fc7java8\u7684toMap\u65b9\u6cd5\u5c06\u96c6\u5408\u4e2d\u7684\u952e\u503c\u5bf9\u8c03\uff0c\u7136\u540e\u53d1\u6325\u7ec4\u5408\u597d\u7684\u96c6\u5408\u3002<\/p>\n\n\n\n<p>\u901a\u8fc7\u8fd9\u79cd\u65b9\u5f0f\u53ef\u4ee5\u83b7\u53d6\u5230\u4e00\u4e2a\u65b0\u7684\u952e\u503c\u5bf9\u8c03\u540e\u7684\u96c6\u5408\uff0c\u90a3\u4e48\u4e3e\u4e00\u53cd\u4e09\u5176\u5b9e\u4e5f\u53ef\u4ee5\u83b7\u53d6\u4e00\u4e2a\u5b9e\u4f53\u4e2d\u7684\u4e24\u4e2a\u5b57\u6bb5\u505a\u4e00\u4e2amap\u96c6\u5408\uff0c\u8fd9\u6837\u5728\u505a\u67e5\u8be2\u7684\u65f6\u5019\u5c31\u4e0d\u9700\u8981\u505a\u4e24\u904d\u5faa\u73af\u67e5\u627e\u6570\u636e\u4e86\uff0c\u4ece\u800c\u964d\u4f4e\u65f6\u95f4\u590d\u6742\u5ea6\u63d0\u5347\u4ee3\u7801\u8fd0\u884c\u6548\u7387\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code lang=\"java\" class=\"language-java\">Map&lt;String, String&gt; userMap = userList.stream().collect(Collectors.toMap(User::getName, User::getPhone));<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"<p>\u76ee\u7684\uff1a\u56e0\u4e3a\u5728\u5f00\u53d1\u8fc7\u7a0b\u4e2d\u4f1a\u4f7f\u7528\u5230\u5b57\u5178\uff0c\u901a\u8fc7\u5b9e\u4f53\u4e2d\u7684\u5b57\u5178\u5b57\u6bb5\u505a\u5bf9\u7167\uff0c\u4e4b\u524d\u9879\u76ee\u4e2d\u5927\u591a\u6570\u662f\u901a\u8fc7\u6ce8\u89e3\u53bb\u505a\u5b57\u5178\u5bf9\u7167\u7684\uff0c\u53ea\u9700 &hellip; <\/p>\n<p class=\"link-more\"><a href=\"https:\/\/www.coffecat.cn\/index.php\/2023\/12\/01\/java8-stream%e6%b5%81%e4%b9%8bmap%e9%9b%86%e5%90%88%e9%94%ae%e5%80%bc%e5%af%b9%e6%8d%a2\/\" class=\"more-link\">\u7ee7\u7eed\u9605\u8bfb<span class=\"screen-reader-text\">\u201cJava8 Stream\u6d41\u4e4bmap\u96c6\u5408\u952e\u503c\u5bf9\u6362\u201d<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6],"tags":[8,10,9,11],"class_list":["post-205","post","type-post","status-publish","format-standard","hentry","category-scatteredtechnicalpoints","tag-java8","tag-map","tag-stream","tag-11"],"views":625,"_links":{"self":[{"href":"https:\/\/www.coffecat.cn\/index.php\/wp-json\/wp\/v2\/posts\/205","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.coffecat.cn\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.coffecat.cn\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.coffecat.cn\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.coffecat.cn\/index.php\/wp-json\/wp\/v2\/comments?post=205"}],"version-history":[{"count":18,"href":"https:\/\/www.coffecat.cn\/index.php\/wp-json\/wp\/v2\/posts\/205\/revisions"}],"predecessor-version":[{"id":664,"href":"https:\/\/www.coffecat.cn\/index.php\/wp-json\/wp\/v2\/posts\/205\/revisions\/664"}],"wp:attachment":[{"href":"https:\/\/www.coffecat.cn\/index.php\/wp-json\/wp\/v2\/media?parent=205"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.coffecat.cn\/index.php\/wp-json\/wp\/v2\/categories?post=205"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.coffecat.cn\/index.php\/wp-json\/wp\/v2\/tags?post=205"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}