{"id":203870,"date":"2025-05-22T14:20:27","date_gmt":"2025-05-22T06:20:27","guid":{"rendered":"https:\/\/server.hk\/cnblog\/203870\/"},"modified":"2025-05-22T14:20:27","modified_gmt":"2025-05-22T06:20:27","slug":"java%e6%b3%9b%e5%9e%8blist","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/203870\/","title":{"rendered":"Java\u6cdb\u578bList"},"content":{"rendered":"<p><b><\/b>     <\/p>\n<h1>Java\u6cdb\u578bList<\/h1>\n<p>\u600e\u4e48\u5165\u95e8\u6587\u7ae0\u7f16\u7a0b\uff1f\u9700\u8981\u5b66\u4e60\u54ea\u4e9b\u77e5\u8bc6\u70b9\uff1f\u8fd9\u662f\u65b0\u624b\u4eec\u521a\u63a5\u89e6\u7f16\u7a0b\u65f6\u5e38\u89c1\u7684\u95ee\u9898\uff1b\u4e0b\u9762\u5c31\u6765\u7ed9\u5927\u5bb6\u6574\u7406\u5206\u4eab\u4e00\u4e9b\u77e5\u8bc6\u70b9\uff0c\u5e0c\u671b\u80fd\u591f\u7ed9\u521d\u5b66\u8005\u4e00\u4e9b\u5e2e\u52a9\u3002\u672c\u7bc7\u6587\u7ae0\u5c31\u6765\u4ecb\u7ecd\u300aJava\u6cdb\u578bList\u300b\uff0c\u6d89\u53ca\u5230\uff0c\u6709\u9700\u8981\u7684\u53ef\u4ee5\u6536\u85cf\u4e00\u4e0b<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/www.17golang.com\/uploads\/20241129\/17328807486749a96cc3db0.jpg\" class=\"aligncenter\"><\/p>\n<p><strong>Java\u6cdb\u578b\u4e2dList&lt;? extends Base&gt;\u7684\u7591\u95ee\u89e3\u7b54<\/strong><\/p>\n<p>\u5728Java\u6cdb\u578b\u4e2d\uff0cList&lt;? extends Base&gt;\u7684\u6cdb\u578b\u7c7b\u578b\u8868\u793a\u6b64\u5217\u8868\u4e2d\u5305\u542b\u7684\u662fBase\u7c7b\u578b\u6216\u5176\u5b50\u7c7b\u7684\u5bf9\u8c61\u3002\u7136\u800c\uff0c\u5b83\u4e0eList&lt;? super Base&gt;\u4e0d\u540c\uff0c\u540e\u8005\u8868\u793a\u5217\u8868\u4e2d\u5305\u542b\u7684\u662fBase\u7c7b\u578b\u53ca\u5176\u8d85\u7c7b\u7684\u5bf9\u8c61\u3002<\/p>\n<p>\u5bf9\u4e8eList&lt;? extends Base&gt;\uff0c\u6211\u4eec\u53ef\u4ee5\u7406\u89e3\u5176\u6cdb\u578b\u7c7b\u578b\u76f8\u5f53\u4e8eList&lt;Base&gt;\u6216List&lt;Sub&gt;\uff0c\u5176\u4e2dSub\u662fBase\u7684\u5b50\u7c7b\u3002\u90a3\u4e48\uff0c\u95ee\u9898\u662f\uff0c\u4e3a\u4ec0\u4e48\u4e0d\u80fd\u8c03\u7528List&lt;? extends Base&gt;\u7684add\u65b9\u6cd5\u6dfb\u52a0\u5bf9\u8c61\uff0c\u5373\u4f7f\u6dfb\u52a0\u7684\u662fBase\u5b9e\u4f8b\uff1f<\/p>\n<p>\u539f\u56e0\u5728\u4e8e\uff0cList&lt;? extends Base&gt;\u8868\u793a\u5217\u8868\u4e2d\u7684\u5bf9\u8c61\u662fBase\u6216\u5176\u5b50\u7c7b\u7684\u672a\u77e5\u7c7b\u578b\u3002\u7531\u4e8e\u4e0d\u77e5\u9053\u786e\u5207\u7684\u7c7b\u578b\uff0c\u56e0\u6b64\u65e0\u6cd5\u786e\u5b9a\u53ef\u4ee5\u6dfb\u52a0\u7684\u5bf9\u8c61\u7c7b\u578b\u3002\u4f8b\u5982\uff0c\u5982\u679cList&lt;? extends Base&gt;\u5b9e\u9645\u7c7b\u578b\u4e3aList&lt;Sub&gt;\uff0c\u800c\u6211\u4eec\u5c1d\u8bd5\u6dfb\u52a0Base\u5b9e\u4f8b\uff0c\u7f16\u8bd1\u5668\u65e0\u6cd5\u786e\u5b9a\u8be5Base\u5b9e\u4f8b\u662f\u5426\u517c\u5bb9Sub\u7c7b\u578b\u3002\u56e0\u6b64\uff0c\u4e3a\u4e86\u4fdd\u8bc1\u7c7b\u578b\u5b89\u5168\uff0cJava\u7981\u6b62\u5f80List&lt;? extends Base&gt;\u4e2d\u6dfb\u52a0\u4efb\u4f55\u5bf9\u8c61\u3002<\/p>\n<p>\u76f8\u6bd4\u4e4b\u4e0b\uff0cList&lt;? super Base&gt;\u8868\u793a\u5217\u8868\u4e2d\u7684\u5bf9\u8c61\u662fBase\u6216\u5176\u8d85\u7c7b\u7684\u672a\u77e5\u7c7b\u578b\u3002\u5728\u8fd9\u79cd\u60c5\u51b5\u4e0b\uff0c\u6211\u4eec\u53ef\u4ee5\u6dfb\u52a0Base\u5b9e\u4f8b\u6216\u5176\u4efb\u4f55\u8d85\u7c7b\u5b9e\u4f8b\uff0c\u56e0\u4e3a\u5b83\u4eec\u662fBase\u7c7b\u578b\u7684\u8d85\u7c7b\u578b\uff0c\u8fd9\u4fdd\u8bc1\u4e86\u7c7b\u578b\u5b89\u5168\u3002<\/p>\n<p>\u56e0\u6b64\uff0cList&lt;? extends Base&gt;\u53ea\u80fd\u7528\u4e8e\u8bfb\u53d6\u5bf9\u8c61\uff0c\u800cList&lt;? super Base&gt;\u53ea\u80fd\u7528\u4e8e\u5199\u5165\u5bf9\u8c61\u3002<\/p>\n<p>\u5230\u8fd9\u91cc\uff0c\u6211\u4eec\u4e5f\u5c31\u8bb2\u5b8c\u4e86\u300aJava\u6cdb\u578bList\u300b\u7684\u5185\u5bb9\u4e86\u3002\u4e2a\u4eba\u8ba4\u4e3a\uff0c\u57fa\u7840\u77e5\u8bc6\u7684\u5b66\u4e60\u548c\u5de9\u56fa\uff0c\u662f\u4e3a\u4e86\u66f4\u597d\u7684\u5c06\u5176\u8fd0\u7528\u5230\u9879\u76ee\u4e2d\uff0c\u6b22\u8fce\u5173\u6ce8\u516c\u4f17\u53f7\uff0c\u5e26\u4f60\u4e86\u89e3\u66f4\u591a\u5173\u4e8e\u7684\u77e5\u8bc6\u70b9\uff01<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Java\u6cdb\u578bList \u600e\u4e48\u5165\u95e8\u6587&#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-203870","post","type-post","status-publish","format-standard","hentry","category-4925"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/203870","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=203870"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/203870\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=203870"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=203870"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=203870"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}