{"id":35018,"date":"2024-11-26T13:42:04","date_gmt":"2024-11-26T05:42:04","guid":{"rendered":"https:\/\/fwq.ai\/blog\/35018\/"},"modified":"2024-11-26T13:42:04","modified_gmt":"2024-11-26T05:42:04","slug":"java%e6%80%8e%e4%b9%88%e8%8e%b7%e5%8f%96%e6%95%b0%e7%bb%84%e7%ac%ac%e4%b8%80%e6%9d%a1","status":"publish","type":"post","link":"https:\/\/fwq.ai\/blog\/35018\/","title":{"rendered":"java\u600e\u4e48\u83b7\u53d6\u6570\u7ec4\u7b2c\u4e00\u6761"},"content":{"rendered":"<blockquote><p>\n  \u83b7\u53d6 java \u6570\u7ec4\u7684\u7b2c\u4e00\u6761\u5143\u7d20\u6709\u4e24\u79cd\u65b9\u6cd5\uff1a1. \u4f7f\u7528\u7d22\u5f15\u6cd5\uff1aarr[0]\uff1b2. \u4f7f\u7528 arrays.stream(arr).findfirst() \u65b9\u6cd5\u8fd4\u56de optionalint \u5bf9\u8c61\u3002\u5728\u6027\u80fd\u4e0a\uff0c\u7d22\u5f15\u6cd5\u901a\u5e38\u4f18\u4e8e\u540e\u8005\u3002\n<\/p><\/blockquote>\n<p><img decoding=\"async\" src=\"https:\/\/img.php.cn\/upload\/article\/202411\/03\/2024110308281093053.jpg\" class=\"aligncenter\" title=\"java\u600e\u4e48\u83b7\u53d6\u6570\u7ec4\u7b2c\u4e00\u6761\u63d2\u56fe\" alt=\"java\u600e\u4e48\u83b7\u53d6\u6570\u7ec4\u7b2c\u4e00\u6761\u63d2\u56fe\" \/><\/p>\n<p><strong>\u5982\u4f55\u83b7\u53d6 Java \u6570\u7ec4\u7684\u7b2c\u4e00\u6761\u5143\u7d20<\/strong><\/p>\n<p>\u83b7\u53d6 Java \u6570\u7ec4\u7684\u7b2c\u4e00\u6761\u5143\u7d20\u6709\u4e24\u79cd\u5e38\u89c1\u65b9\u6cd5\uff1a<\/p>\n<p><strong>1. \u7d22\u5f15\u6cd5<\/strong><\/p>\n<p>\u8fd9\u662f\u6700\u76f4\u63a5\u7684\u65b9\u6cd5\uff0c\u901a\u8fc7\u4f7f\u7528\u6570\u7ec4\u7684\u7d22\u5f15 0 \u6765\u8bbf\u95ee\u7b2c\u4e00\u6761\u5143\u7d20\u3002<\/p>\n<p><span>\u7acb\u5373\u5b66\u4e60<\/span>\u201c\u201d\uff1b<\/p>\n<pre>int[] arr = {1, 2, 3, 4, 5};\nint firstElement = arr[0];\nSystem.out.println(firstElement); \/\/ \u8f93\u51fa\uff1a1<\/pre>\n<p> \u767b\u5f55\u540e\u590d\u5236 <\/p>\n<p><strong>2. Arrays.stream(arr).findFirst() \u65b9\u6cd5<\/strong><\/p>\n<p>Arrays.stream(arr).findFirst() \u8fd4\u56de\u4e00\u4e2a OptionalInt \u5bf9\u8c61\uff0c\u5b83\u53ef\u4ee5\u8868\u793a\u7b2c\u4e00\u4e2a\u5143\u7d20\u7684\u503c\uff0c\u4e5f\u53ef\u4ee5\u8868\u793a\u6570\u7ec4\u4e3a\u7a7a\u65f6\u7684\u7a7a\u503c\u3002<\/p>\n<pre>int[] arr = {1, 2, 3, 4, 5};\nOptionalInt firstElement = Arrays.stream(arr).findFirst();\nif (firstElement.isPresent()) {\n    System.out.println(firstElement.getAsInt()); \/\/ \u8f93\u51fa\uff1a1\n} else {\n    System.out.println(\"\u6570\u7ec4\u4e3a\u7a7a\");\n}<\/pre>\n<p> \u767b\u5f55\u540e\u590d\u5236 <\/p>\n<p><strong>\u6027\u80fd\u8003\u8651<\/strong><\/p>\n<p>\u5728\u5927\u591a\u6570\u60c5\u51b5\u4e0b\uff0c\u4f7f\u7528\u7d22\u5f15\u6cd5\u83b7\u53d6\u7b2c\u4e00\u6761\u5143\u7d20\u7684\u6027\u80fd\u8981\u4f18\u4e8e Arrays.stream(arr).findFirst() \u65b9\u6cd5\u3002\u540e\u8005\u9700\u8981\u521b\u5efa\u6d41\u5e76\u8fdb\u884c\u8fc7\u6ee4\uff0c\u8fd9\u6bd4\u76f4\u63a5\u8bbf\u95ee\u6570\u7ec4\u5143\u7d20\u66f4\u8017\u65f6\u3002<\/p>\n<p>\u4ee5\u4e0a\u5c31\u662fjava\u600e\u4e48\u83b7\u53d6\u6570\u7ec4\u7b2c\u4e00\u6761\u7684\u8be6\u7ec6\u5185\u5bb9\uff0c\u66f4\u591a\u8bf7\u5173\u6ce8\u7c73\u4e91\u5176\u5b83\u76f8\u5173\u6587\u7ae0\uff01<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u83b7\u53d6 java \u6570\u7ec4\u7684\u7b2c\u4e00\u6761\u5143\u7d20\u6709\u4e24\u79cd\u65b9\u6cd5\uff1a1. \u4f7f\u7528\u7d22\u5f15\u6cd5\uff1aarr[0]\uff1b2. \u4f7f\u7528 arrays.stream(arr).findfirst() \u65b9\u6cd5\u8fd4\u56de optionalint \u5bf9\u8c61\u3002\u5728\u6027\u80fd\u4e0a\uff0c\u7d22\u5f15\u6cd5\u901a\u5e38\u4f18\u4e8e\u540e\u8005\u3002 \u5982\u4f55\u83b7\u53d6 Java \u6570\u7ec4\u7684\u7b2c\u4e00\u6761\u5143\u7d20 \u83b7\u53d6 Java \u6570\u7ec4\u7684\u7b2c\u4e00\u6761\u5143\u7d20\u6709\u4e24\u79cd\u5e38\u89c1\u65b9\u6cd5\uff1a 1. \u7d22\u5f15\u6cd5 \u8fd9\u662f\u6700\u76f4\u63a5\u7684\u65b9\u6cd5\uff0c\u901a\u8fc7\u4f7f\u7528\u6570\u7ec4\u7684\u7d22\u5f15 0 \u6765\u8bbf\u95ee\u7b2c\u4e00\u6761\u5143\u7d20\u3002 \u7acb\u5373\u5b66\u4e60\u201c\u201d\uff1b int[] arr = {1, 2, 3, 4, 5}; int firstElement = arr[0]; System.out.println(firstElement); \/\/ \u8f93\u51fa\uff1a1 \u767b\u5f55\u540e\u590d\u5236 2. Arrays.stream(arr).findFirst() \u65b9\u6cd5 Arrays.stream(arr).findFirst() \u8fd4\u56de\u4e00\u4e2a OptionalInt \u5bf9\u8c61\uff0c\u5b83\u53ef\u4ee5\u8868\u793a\u7b2c\u4e00\u4e2a\u5143\u7d20\u7684\u503c\uff0c\u4e5f\u53ef\u4ee5\u8868\u793a\u6570\u7ec4\u4e3a\u7a7a\u65f6\u7684\u7a7a\u503c\u3002 int[] arr = {1, 2, 3, 4, 5}; OptionalInt firstElement = [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[16],"tags":[],"class_list":["post-35018","post","type-post","status-publish","format-standard","hentry","category-16"],"_links":{"self":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/35018","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/comments?post=35018"}],"version-history":[{"count":0,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/35018\/revisions"}],"wp:attachment":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/media?parent=35018"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/categories?post=35018"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/tags?post=35018"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}