{"id":64420,"date":"2026-01-23T14:16:45","date_gmt":"2026-01-23T06:16:45","guid":{"rendered":"https:\/\/www.wsisp.com\/helps\/64420.html"},"modified":"2026-01-23T14:16:45","modified_gmt":"2026-01-23T06:16:45","slug":"%e7%ba%bf%e7%a8%8b%e5%ae%89%e5%85%a8%e9%9b%86%e5%90%88%ef%bc%9acopyonwritearraylist-%e7%9a%84%e9%80%82%e7%94%a8%e5%9c%ba%e6%99%af%e4%b8%8e%e6%80%a7%e8%83%bd%e4%bb%a3%e4%bb%b7","status":"publish","type":"post","link":"https:\/\/www.wsisp.com\/helps\/64420.html","title":{"rendered":"\u7ebf\u7a0b\u5b89\u5168\u96c6\u5408\uff1aCopyOnWriteArrayList \u7684\u9002\u7528\u573a\u666f\u4e0e\u6027\u80fd\u4ee3\u4ef7"},"content":{"rendered":"<\/p>\n<h4>\u6587\u7ae0\u76ee\u5f55<\/h4>\n<ul>\n<li>&#x1f3af;&#x1f525; \u7ebf\u7a0b\u5b89\u5168\u96c6\u5408&#xff1a;CopyOnWriteArrayList \u7684\u9002\u7528\u573a\u666f\u4e0e\u6027\u80fd\u4ee3\u4ef7<\/li>\n<li>\n<ul>\n<li>\n<ul>\n<li>&#x1f31f;&#x1f30d; \u5f15\u8a00&#xff1a;\u5e76\u53d1\u5bb9\u5668\u7684\u201c\u4e2d\u5eb8\u4e4b\u9053\u201d<\/li>\n<li>&#x1f4ca;&#x1f4cb; \u7b2c\u4e00\u7ae0&#xff1a;\u5e95\u5c42\u539f\u7406\u2014\u2014\u4e3a\u4ec0\u4e48\u8bfb\u591a\u5199\u5c11\u573a\u666f\u975e\u5b83\u4e0d\u53ef&#xff1f;<\/li>\n<li>\n<ul>\n<li>&#x1f9ec;&#x1f9e9; 1.1 \u201c\u5199\u65f6\u590d\u5236\u201d\u7684\u7269\u7406\u672c\u8d28<\/li>\n<li>&#x1f6e1;\ufe0f\u2696\ufe0f 1.2 \u4e3a\u4ec0\u4e48\u8bfb\u64cd\u4f5c\u4e0d\u9700\u8981\u9501&#xff1f;<\/li>\n<li>&#x1f4c9;\u26a0\ufe0f 1.3 \u8fed\u4ee3\u5668\u7684\u201c\u514d\u6b7b\u91d1\u724c\u201d<\/li>\n<li>&#x1f4bb;&#x1f680; \u4ee3\u7801\u5b9e\u6218&#xff1a;\u8bfb\u5199\u5206\u79bb\u7684\u6027\u80fd\u4eff\u771f<\/li>\n<\/ul>\n<\/li>\n<li>&#x1f504;&#x1f9f1; \u7b2c\u4e8c\u7ae0&#xff1a;\u5b9e\u6218\u6f14\u7ec3\u2014\u2014\u9ad8\u53ef\u9760\u7f13\u5b58\u66f4\u65b0\u7b56\u7565<\/li>\n<li>\n<ul>\n<li>&#x1f9ec;&#x1f9e9; 2.1 \u6700\u7ec8\u4e00\u81f4\u6027 vs. \u5f3a\u4e00\u81f4\u6027<\/li>\n<li>&#x1f6e1;\ufe0f\u2696\ufe0f 2.2 \u5185\u5b58\u4ee3\u4ef7\u7684\u7cbe\u7b97<\/li>\n<li>&#x1f4bb;&#x1f680; \u5b9e\u6218\u4ee3\u7801&#xff1a;\u9ad8\u6027\u80fd\u914d\u7f6e\u7ba1\u7406\u5668<\/li>\n<\/ul>\n<\/li>\n<li>&#x1f30d;&#x1f4c8; \u7b2c\u4e09\u7ae0&#xff1a;\u7ef4\u5ea6\u5bf9\u6bd4\u2014\u2014CopyOnWriteArrayList vs. ConcurrentHashMap<\/li>\n<li>\n<ul>\n<li>&#x1f4cf;\u2696\ufe0f 3.1 \u9501\u7684\u7c92\u5ea6\u535a\u5f08<\/li>\n<li>&#x1f4c9;&#x1f3b2; 3.2 \u8bfb\u6027\u80fd\u7684\u5dee\u5f02<\/li>\n<li>&#x1f522;\u26a1 3.3 \u8fed\u4ee3\u5668\u8bed\u4e49\u7684\u4e0d\u540c<\/li>\n<li>&#x1f4bb;&#x1f680; \u9009\u578b\u903b\u8f91\u4ee3\u7801\u793a\u4f8b<\/li>\n<\/ul>\n<\/li>\n<li>\u26a0\ufe0f&#x1f4c9; \u7b2c\u56db\u7ae0&#xff1a;\u9634\u6697\u9762\u2014\u2014CopyOnWriteArrayList \u7684\u6027\u80fd\u9677\u9631\u4e0e\u4ee3\u4ef7<\/li>\n<li>\n<ul>\n<li>&#x1f9ec;&#x1f9e9; 4.1 \u5185\u5b58\u7206\u70b8&#xff08;Memory Overhead&#xff09;<\/li>\n<li>&#x1f6e1;\ufe0f\u2696\ufe0f 4.2 \u6570\u636e\u7684\u201c\u5ef6\u8fdf\u53ef\u89c1\u201d<\/li>\n<li>&#x1f504;&#x1f9f1; 4.3 \u5199\u6027\u80fd\u7684\u65ad\u5d16\u5f0f\u4e0b\u8dcc<\/li>\n<\/ul>\n<\/li>\n<li>&#x1f31f;&#x1f3af; \u7b2c\u4e94\u7ae0&#xff1a;\u603b\u7ed3\u4e0e\u9009\u578b\u6307\u5357\u2014\u2014\u5982\u4f55\u4f18\u96c5\u5730\u9009\u62e9\u5e76\u53d1\u5bb9\u5668&#xff1f;<\/li>\n<li>\n<ul>\n<li>&#x1f9ec;&#x1f9e9; \u67b6\u6784\u5e08\u603b\u7ed3&#xff1a;<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<h2>&#x1f3af;&#x1f525; \u7ebf\u7a0b\u5b89\u5168\u96c6\u5408&#xff1a;CopyOnWriteArrayList \u7684\u9002\u7528\u573a\u666f\u4e0e\u6027\u80fd\u4ee3\u4ef7<\/h2>\n<h4>&#x1f31f;&#x1f30d; \u5f15\u8a00&#xff1a;\u5e76\u53d1\u5bb9\u5668\u7684\u201c\u4e2d\u5eb8\u4e4b\u9053\u201d<\/h4>\n<p>\u5728\u591a\u7ebf\u7a0b\u7f16\u7a0b\u7684\u5e7f\u9614\u7586\u57df\u4e2d&#xff0c;\u5f00\u53d1\u8005\u59cb\u7ec8\u5728\u5bfb\u627e\u4e00\u79cd\u5e73\u8861&#xff1a;\u5982\u4f55\u5728\u4fdd\u8bc1\u7ebf\u7a0b\u5b89\u5168\u7684\u524d\u63d0\u4e0b&#xff0c;\u6700\u5927\u9650\u5ea6\u5730\u63d0\u5347\u7cfb\u7edf\u7684\u541e\u5410\u91cf&#xff1f;<\/p>\n<p>\u65e9\u671f\u7684 Java \u7ed9\u4e86\u6211\u4eec Vector \u548c Collections.synchronizedList\u3002\u5b83\u4eec\u7b80\u5355\u7c97\u66b4&#xff0c;\u901a\u8fc7\u5728\u6bcf\u4e2a\u65b9\u6cd5\u4e0a\u52a0 synchronized \u9501\u6765\u4fdd\u8bc1\u5b89\u5168\u3002\u8fd9\u79cd\u201c\u4e00\u5200\u5207\u201d\u7684\u505a\u6cd5\u5728\u5355\u6838\u65f6\u4ee3\u6216\u8bb8\u5c1a\u80fd\u5e94\u4ed8&#xff0c;\u4f46\u5728\u5982\u4eca\u52a8\u8f84\u6570\u5341\u6838\u7684 CPU \u9762\u524d&#xff0c;\u5176\u4e25\u91cd\u7684\u9501\u7ade\u4e89\u76f4\u63a5\u8ba9\u6027\u80fd\u8dcc\u5165\u8c37\u5e95\u3002<\/p>\n<p>\u968f\u540e&#xff0c;ReentrantReadWriteLock&#xff08;\u8bfb\u5199\u9501&#xff09;\u8bd5\u56fe\u4f18\u5316\u8fd9\u4e00\u5c40\u9762&#xff0c;\u63d0\u51fa\u4e86\u201c\u8bfb\u8bfb\u5171\u4eab\u3001\u8bfb\u5199\u4e92\u65a5\u3001\u5199\u5199\u4e92\u65a5\u201d\u7684\u903b\u8f91\u3002\u7136\u800c&#xff0c;\u5373\u4fbf\u5982\u6b64&#xff0c;\u8bfb\u9501\u4e0e\u5199\u9501\u4e4b\u95f4\u4f9d\u7136\u5b58\u5728\u7ade\u4e89\u3002\u4e3a\u4e86\u8ffd\u6c42\u6781\u81f4\u7684\u201c\u8bfb\u6027\u80fd\u201d&#xff0c;Java \u5e76\u53d1\u5927\u5e08 Doug Lea \u4e3a\u6211\u4eec\u5e26\u6765\u4e86 CopyOnWriteArrayList (COWAL)\u3002\u5b83\u91c7\u7528\u4e86\u4e00\u79cd\u8fd1\u4e4e\u201c\u65e0\u60c5\u201d\u7684\u7b56\u7565&#xff1a;\u653e\u5f03\u5f3a\u4e00\u81f4\u6027&#xff0c;\u901a\u8fc7\u727a\u7272\u5199\u64cd\u4f5c\u7684\u6602\u8d35\u5185\u5b58\u548c\u65f6\u95f4&#xff0c;\u6362\u53d6\u8bfb\u64cd\u4f5c\u7684\u96f6\u9501\u5b9a\u3002<\/p>\n<p>\u4eca\u5929&#xff0c;\u6211\u4eec\u5c06\u8de8\u8d8a API \u7684\u8868\u8c61&#xff0c;\u6df1\u5165 JVM \u5185\u6838&#xff0c;\u62c6\u89e3\u8fd9\u4e00\u201c\u5199\u65f6\u590d\u5236\u201d\u5929\u624d\u8bbe\u8ba1\u7684\u5e95\u5c42\u903b\u8f91&#xff0c;\u5e76\u63ed\u793a\u5b83\u5728\u9ad8\u6027\u80fd\u67b6\u6784\u4e2d\u4e0d\u53ef\u66ff\u4ee3\u7684\u5730\u4f4d\u3002<\/p>\n<hr \/>\n<h4>&#x1f4ca;&#x1f4cb; \u7b2c\u4e00\u7ae0&#xff1a;\u5e95\u5c42\u539f\u7406\u2014\u2014\u4e3a\u4ec0\u4e48\u8bfb\u591a\u5199\u5c11\u573a\u666f\u975e\u5b83\u4e0d\u53ef&#xff1f;<\/h4>\n<h5>&#x1f9ec;&#x1f9e9; 1.1 \u201c\u5199\u65f6\u590d\u5236\u201d\u7684\u7269\u7406\u672c\u8d28<\/h5>\n<p>CopyOnWriteArrayList \u7684\u6838\u5fc3\u601d\u60f3\u6e90\u4e8e\u64cd\u4f5c\u7cfb\u7edf\u5c42\u9762\u7684 Copy-On-Write (COW) \u6280\u672f\u3002\u5728 Linux \u7cfb\u7edf\u4e2d&#xff0c;\u5f53\u7236\u8fdb\u7a0b fork \u51fa\u5b50\u7ebf\u7a0b\u65f6&#xff0c;\u5e76\u4e0d\u4f1a\u7acb\u5373\u590d\u5236\u7269\u7406\u5185\u5b58&#xff0c;\u800c\u662f\u5171\u4eab\u540c\u4e00\u5757\u5185\u5b58&#xff0c;\u76f4\u5230\u5176\u4e2d\u4e00\u4e2a\u8fdb\u7a0b\u5c1d\u8bd5\u4fee\u6539&#xff0c;\u624d\u4f1a\u89e6\u53d1\u7269\u7406\u5185\u5b58\u7684\u590d\u5236\u3002<\/p>\n<p>\u5728 Java \u4e2d&#xff0c;COWAL \u5b8c\u7f8e\u590d\u523b\u4e86\u8fd9\u4e00\u903b\u8f91\u3002\u5b83\u7684\u5185\u90e8\u7ef4\u62a4\u4e86\u4e00\u4e2a volatile \u4fee\u9970\u7684\u6570\u7ec4\u3002<\/p>\n<ul>\n<li>\u8bfb\u53d6\u65f6&#xff1a;\u76f4\u63a5\u8bfb\u53d6\u5f53\u524d\u6570\u7ec4&#xff0c;\u4e0d\u52a0\u4efb\u4f55\u9501\u3002<\/li>\n<li>\u5199\u5165\u65f6&#xff1a;\u5148\u5c06\u5f53\u524d\u6570\u7ec4\u590d\u5236\u51fa\u4e00\u4efd\u526f\u672c&#xff08;Copy&#xff09;&#xff0c;\u5728\u526f\u672c\u4e0a\u8fdb\u884c\u4fee\u6539&#xff08;Add\/Set\/Remove&#xff09;&#xff0c;\u4fee\u6539\u5b8c\u6210\u540e&#xff0c;\u518d\u5c06\u5185\u90e8\u6570\u7ec4\u7684\u5f15\u7528\u6307\u5411\u8fd9\u4e2a\u65b0\u526f\u672c\u3002<\/li>\n<\/ul>\n<h5>&#x1f6e1;\ufe0f\u2696\ufe0f 1.2 \u4e3a\u4ec0\u4e48\u8bfb\u64cd\u4f5c\u4e0d\u9700\u8981\u9501&#xff1f;<\/h5>\n<p>\u8bfb\u64cd\u4f5c\u4e4b\u6240\u4ee5\u4e0d\u9700\u8981\u9501&#xff0c;\u662f\u56e0\u4e3a volatile \u5173\u952e\u5b57\u4fdd\u8bc1\u4e86\u53ef\u89c1\u6027\u3002\u5f53\u5199\u7ebf\u7a0b\u5b8c\u6210\u526f\u672c\u66ff\u6362\u5e76\u6267\u884c setArray(newArray) \u65f6&#xff0c;\u6839\u636e JMM \u7684 Happens-Before \u539f\u5219&#xff0c;\u540e\u7eed\u7684\u6240\u6709\u8bfb\u7ebf\u7a0b\u90fd\u80fd\u7acb\u5373\u611f\u77e5\u5230\u5f15\u7528\u7684\u53d8\u5316\u3002<\/p>\n<p>\u66f4\u91cd\u8981\u7684\u662f&#xff0c;\u8bfb\u7ebf\u7a0b\u5728\u8bfb\u53d6\u77ac\u95f4\u83b7\u53d6\u7684\u662f\u6570\u7ec4\u7684\u5feb\u7167&#xff08;Snapshot&#xff09;\u3002\u5373\u4fbf\u5199\u7ebf\u7a0b\u6b63\u5728\u540e\u53f0\u75af\u72c2\u5730\u590d\u5236\u548c\u4fee\u6539&#xff0c;\u8bfb\u7ebf\u7a0b\u4f9d\u7136\u5728\u65e7\u6570\u7ec4\u4e0a\u4f18\u54c9\u6e38\u54c9\u5730\u904d\u5386&#xff0c;\u4e92\u4e0d\u5e72\u6270\u3002\u8fd9\u79cd\u201c\u65f6\u7a7a\u9694\u79bb\u201d\u7684\u8bbe\u8ba1&#xff0c;\u5f7b\u5e95\u6d88\u9664\u4e86\u8bfb\u5199\u7ade\u4e89\u3002<\/p>\n<h5>&#x1f4c9;\u26a0\ufe0f 1.3 \u8fed\u4ee3\u5668\u7684\u201c\u514d\u6b7b\u91d1\u724c\u201d<\/h5>\n<p>\u5728\u666e\u901a\u7684 ArrayList \u4e2d&#xff0c;\u5982\u679c\u5728\u904d\u5386\u65f6\u4fee\u6539\u96c6\u5408&#xff0c;\u4f1a\u89e6\u53d1\u81ed\u540d\u662d\u8457\u7684 ConcurrentModificationException\u3002\u800c COWAL \u7684\u8fed\u4ee3\u5668\u662f Fail-Safe \u7684\u3002\u56e0\u4e3a\u5b83\u904d\u5386\u7684\u662f\u521b\u5efa\u8fed\u4ee3\u5668\u90a3\u4e00\u523b\u7684\u5feb\u7167&#xff0c;\u65b0\u6570\u7ec4\u7684\u4ea7\u751f\u4e0d\u4f1a\u5f71\u54cd\u65e7\u8fed\u4ee3\u5668\u7684\u8fd0\u884c\u3002\u8fd9\u4f7f\u5f97\u5b83\u5728\u9700\u8981\u9891\u7e41\u904d\u5386\u96c6\u5408\u7684\u5e76\u53d1\u573a\u666f\u4e2d\u5177\u6709\u964d\u7ef4\u6253\u51fb\u822c\u7684\u4f18\u52bf\u3002<\/p>\n<hr \/>\n<h5>&#x1f4bb;&#x1f680; \u4ee3\u7801\u5b9e\u6218&#xff1a;\u8bfb\u5199\u5206\u79bb\u7684\u6027\u80fd\u4eff\u771f<\/h5>\n<p><span class=\"token comment\">\/**<br \/>\n * \u6a21\u62df\u9ad8\u5e76\u53d1\u8bfb\u591a\u5199\u5c11\u573a\u666f\u4e0b\u7684 COW \u8868\u73b0<br \/>\n *\/<\/span><br \/>\n<span class=\"token keyword\">public<\/span> <span class=\"token keyword\">class<\/span> <span class=\"token class-name\">COWReadWriteDemo<\/span> <span class=\"token punctuation\">{<\/span><br \/>\n    <span class=\"token keyword\">private<\/span> <span class=\"token keyword\">static<\/span> <span class=\"token keyword\">final<\/span> <span class=\"token class-name\">CopyOnWriteArrayList<\/span><span class=\"token generics\"><span class=\"token punctuation\">&lt;<\/span><span class=\"token class-name\">String<\/span><span class=\"token punctuation\">&gt;<\/span><\/span> WHITE_LIST <span class=\"token operator\">&#061;<\/span> <span class=\"token keyword\">new<\/span> <span class=\"token class-name\">CopyOnWriteArrayList<\/span><span class=\"token generics\"><span class=\"token punctuation\">&lt;<\/span><span class=\"token punctuation\">&gt;<\/span><\/span><span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span><\/p>\n<p>    <span class=\"token keyword\">static<\/span> <span class=\"token punctuation\">{<\/span><br \/>\n        WHITE_LIST<span class=\"token punctuation\">.<\/span><span class=\"token function\">add<\/span><span class=\"token punctuation\">(<\/span><span class=\"token string\">&#034;192.168.1.1&#034;<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span><br \/>\n        WHITE_LIST<span class=\"token punctuation\">.<\/span><span class=\"token function\">add<\/span><span class=\"token punctuation\">(<\/span><span class=\"token string\">&#034;10.0.0.1&#034;<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span><br \/>\n    <span class=\"token punctuation\">}<\/span><\/p>\n<p>    <span class=\"token keyword\">public<\/span> <span class=\"token keyword\">static<\/span> <span class=\"token keyword\">void<\/span> <span class=\"token function\">main<\/span><span class=\"token punctuation\">(<\/span><span class=\"token class-name\">String<\/span><span class=\"token punctuation\">[<\/span><span class=\"token punctuation\">]<\/span> args<span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span><br \/>\n        <span class=\"token comment\">\/\/ 1. \u6a21\u62df\u6d77\u91cf\u5e76\u53d1\u8bfb&#xff08;\u5982\u7f51\u5173\u9274\u6743&#xff09;<\/span><br \/>\n        <span class=\"token keyword\">for<\/span> <span class=\"token punctuation\">(<\/span><span class=\"token keyword\">int<\/span> i <span class=\"token operator\">&#061;<\/span> <span class=\"token number\">0<\/span><span class=\"token punctuation\">;<\/span> i <span class=\"token operator\">&lt;<\/span> <span class=\"token number\">100<\/span><span class=\"token punctuation\">;<\/span> i<span class=\"token operator\">&#043;&#043;<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span><br \/>\n            <span class=\"token keyword\">new<\/span> <span class=\"token class-name\">Thread<\/span><span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token operator\">-&gt;<\/span> <span class=\"token punctuation\">{<\/span><br \/>\n                <span class=\"token keyword\">while<\/span> <span class=\"token punctuation\">(<\/span><span class=\"token boolean\">true<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span><br \/>\n                    <span class=\"token keyword\">for<\/span> <span class=\"token punctuation\">(<\/span><span class=\"token class-name\">String<\/span> ip <span class=\"token operator\">:<\/span> WHITE_LIST<span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span><br \/>\n                        <span class=\"token comment\">\/\/ \u8bfb\u64cd\u4f5c\u65e0\u9700\u9501&#xff0c;\u6781\u901f\u6267\u884c<\/span><br \/>\n                        <span class=\"token function\">doCheck<\/span><span class=\"token punctuation\">(<\/span>ip<span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span><br \/>\n                    <span class=\"token punctuation\">}<\/span><br \/>\n                <span class=\"token punctuation\">}<\/span><br \/>\n            <span class=\"token punctuation\">}<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">.<\/span><span class=\"token function\">start<\/span><span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span><br \/>\n        <span class=\"token punctuation\">}<\/span><\/p>\n<p>        <span class=\"token comment\">\/\/ 2. \u6a21\u62df\u6781\u4f4e\u9891\u7684\u5199&#xff08;\u5982\u540e\u53f0\u7ba1\u7406\u5458\u66f4\u65b0\u9ed1\u540d\u5355&#xff09;<\/span><br \/>\n        <span class=\"token keyword\">new<\/span> <span class=\"token class-name\">Thread<\/span><span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token operator\">-&gt;<\/span> <span class=\"token punctuation\">{<\/span><br \/>\n            <span class=\"token keyword\">try<\/span> <span class=\"token punctuation\">{<\/span><br \/>\n                <span class=\"token class-name\">Thread<\/span><span class=\"token punctuation\">.<\/span><span class=\"token function\">sleep<\/span><span class=\"token punctuation\">(<\/span><span class=\"token number\">5000<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span><br \/>\n                WHITE_LIST<span class=\"token punctuation\">.<\/span><span class=\"token function\">add<\/span><span class=\"token punctuation\">(<\/span><span class=\"token string\">&#034;172.16.0.1&#034;<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span><br \/>\n                <span class=\"token class-name\">System<\/span><span class=\"token punctuation\">.<\/span>out<span class=\"token punctuation\">.<\/span><span class=\"token function\">println<\/span><span class=\"token punctuation\">(<\/span><span class=\"token string\">&#034;\u2705 \u767d\u540d\u5355\u5df2\u66f4\u65b0&#xff0c;\u65b0\u5f15\u7528\u5df2\u751f\u6548&#034;<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span><br \/>\n            <span class=\"token punctuation\">}<\/span> <span class=\"token keyword\">catch<\/span> <span class=\"token punctuation\">(<\/span><span class=\"token class-name\">InterruptedException<\/span> e<span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span><br \/>\n                e<span class=\"token punctuation\">.<\/span><span class=\"token function\">printStackTrace<\/span><span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span><br \/>\n            <span class=\"token punctuation\">}<\/span><br \/>\n        <span class=\"token punctuation\">}<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">.<\/span><span class=\"token function\">start<\/span><span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span><br \/>\n    <span class=\"token punctuation\">}<\/span><\/p>\n<p>    <span class=\"token keyword\">private<\/span> <span class=\"token keyword\">static<\/span> <span class=\"token keyword\">void<\/span> <span class=\"token function\">doCheck<\/span><span class=\"token punctuation\">(<\/span><span class=\"token class-name\">String<\/span> ip<span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span><br \/>\n        <span class=\"token comment\">\/\/ \u8017\u65f6\u6781\u77ed\u7684\u5224\u65ad\u903b\u8f91<\/span><br \/>\n    <span class=\"token punctuation\">}<\/span><br \/>\n<span class=\"token punctuation\">}<\/span><\/p>\n<hr \/>\n<h4>&#x1f504;&#x1f9f1; \u7b2c\u4e8c\u7ae0&#xff1a;\u5b9e\u6218\u6f14\u7ec3\u2014\u2014\u9ad8\u53ef\u9760\u7f13\u5b58\u66f4\u65b0\u7b56\u7565<\/h4>\n<p>\u5728\u5206\u5e03\u5f0f\u67b6\u6784\u4e2d&#xff0c;\u6211\u4eec\u7ecf\u5e38\u9700\u8981\u5904\u7406\u201c\u914d\u7f6e\u4fe1\u606f\u201d\u6216\u201c\u8def\u7531\u8868\u201d\u7684\u672c\u5730\u7f13\u5b58\u3002\u8fd9\u7c7b\u6570\u636e\u901a\u5e38\u901a\u8fc7 MQ \u6216\u5b9a\u65f6\u4efb\u52a1\u4ece\u914d\u7f6e\u4e2d\u5fc3\u62c9\u53d6\u3002<\/p>\n<h5>&#x1f9ec;&#x1f9e9; 2.1 \u6700\u7ec8\u4e00\u81f4\u6027 vs. \u5f3a\u4e00\u81f4\u6027<\/h5>\n<p>\u5f88\u591a\u5f00\u53d1\u8005\u5728\u9762\u5bf9\u914d\u7f6e\u66f4\u65b0\u65f6&#xff0c;\u7b2c\u4e00\u53cd\u5e94\u662f\u52a0 synchronized\u3002\u4f46\u5728\u6bcf\u79d2\u4e07\u7ea7 QPS \u7684\u7f51\u5173\u5c42&#xff0c;\u52a0\u9501\u610f\u5473\u7740\u6392\u961f\u3002COWAL \u63d0\u4f9b\u4e86\u4e00\u79cd\u6700\u7ec8\u4e00\u81f4\u6027\u7684\u65b9\u6848\u3002<\/p>\n<p>\u867d\u7136\u5199\u64cd\u4f5c\u6267\u884c\u7684\u90a3\u4e00\u51e0\u6beb\u79d2\u5185&#xff0c;\u90e8\u5206\u8bfb\u7ebf\u7a0b\u53ef\u80fd\u8fd8\u4f1a\u8bfb\u5230\u65e7\u7684\u914d\u7f6e&#xff0c;\u4f46\u5728\u914d\u7f6e\u4e0b\u53d1\u7684\u573a\u666f\u4e2d&#xff0c;\u8fd9\u79cd\u5fae\u5c0f\u7684\u5ef6\u8fdf\u901a\u5e38\u662f\u53ef\u63a5\u53d7\u7684\u3002\u6362\u53d6\u6765\u7684&#xff0c;\u662f\u8bfb\u64cd\u4f5c 100% \u7684\u975e\u963b\u585e\u6027\u80fd\u3002<\/p>\n<h5>&#x1f6e1;\ufe0f\u2696\ufe0f 2.2 \u5185\u5b58\u4ee3\u4ef7\u7684\u7cbe\u7b97<\/h5>\n<p>\u7531\u4e8e\u6bcf\u6b21\u5199\u64cd\u4f5c\u90fd\u4f1a Arrays.copyOf&#xff0c;\u5982\u679c\u6570\u7ec4\u89c4\u6a21\u8fbe\u5230 10 \u4e07\u7ea7&#xff0c;\u4e00\u6b21\u5199\u64cd\u4f5c\u5c31\u4f1a\u4ea7\u751f\u5de8\u5927\u7684\u77ac\u65f6\u5185\u5b58\u5206\u914d\u3002\u8fd9\u53ef\u80fd\u76f4\u63a5\u5bfc\u81f4 JVM \u89e6\u53d1 Young GC \u751a\u81f3\u662f Full GC\u3002 \u5de5\u4e1a\u7ea7\u5efa\u8bae&#xff1a;COWAL \u5b58\u50a8\u7684\u6570\u636e\u91cf\u4e0d\u5b9c\u8fc7\u5927\u3002\u5b83\u6700\u9002\u5408\u5b58\u50a8\u90a3\u4e9b\u201c\u5c0f\u800c\u7cbe\u201d\u7684\u914d\u7f6e\u6570\u636e&#xff08;\u5982\u9ed1\u540d\u5355\u3001\u8def\u7531\u5143\u6570\u636e\u3001\u52a8\u6001\u5f00\u5173&#xff09;\u3002<\/p>\n<hr \/>\n<h5>&#x1f4bb;&#x1f680; \u5b9e\u6218\u4ee3\u7801&#xff1a;\u9ad8\u6027\u80fd\u914d\u7f6e\u7ba1\u7406\u5668<\/h5>\n<p><span class=\"token comment\">\/**<br \/>\n * \u6a21\u62df\u5fae\u670d\u52a1\u67b6\u6784\u4e2d\u7684\u52a8\u6001\u8def\u7531\u914d\u7f6e\u66f4\u65b0<br \/>\n *\/<\/span><br \/>\n<span class=\"token keyword\">public<\/span> <span class=\"token keyword\">class<\/span> <span class=\"token class-name\">DynamicRouteManager<\/span> <span class=\"token punctuation\">{<\/span><br \/>\n    <span class=\"token comment\">\/\/ \u8def\u7531\u914d\u7f6e\u8868&#xff1a;\u8bfb\u6781\u591a&#xff08;\u6bcf\u7b14\u8bf7\u6c42\u90fd\u8981\u67e5&#xff09;&#xff0c;\u5199\u6781\u5c11&#xff08;\u7ba1\u7406\u5458\u624b\u52a8\u4fee\u6539&#xff09;<\/span><br \/>\n    <span class=\"token keyword\">private<\/span> <span class=\"token keyword\">final<\/span> <span class=\"token class-name\">CopyOnWriteArrayList<\/span><span class=\"token generics\"><span class=\"token punctuation\">&lt;<\/span><span class=\"token class-name\">RouteConfig<\/span><span class=\"token punctuation\">&gt;<\/span><\/span> routes <span class=\"token operator\">&#061;<\/span> <span class=\"token keyword\">new<\/span> <span class=\"token class-name\">CopyOnWriteArrayList<\/span><span class=\"token generics\"><span class=\"token punctuation\">&lt;<\/span><span class=\"token punctuation\">&gt;<\/span><\/span><span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span><\/p>\n<p>    <span class=\"token keyword\">public<\/span> <span class=\"token keyword\">void<\/span> <span class=\"token function\">updateRoutes<\/span><span class=\"token punctuation\">(<\/span><span class=\"token class-name\">List<\/span><span class=\"token generics\"><span class=\"token punctuation\">&lt;<\/span><span class=\"token class-name\">RouteConfig<\/span><span class=\"token punctuation\">&gt;<\/span><\/span> newRoutes<span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span><br \/>\n        <span class=\"token comment\">\/\/ \u6ce8\u610f&#xff1a;\u8fd9\u91cc\u5efa\u8bae\u6279\u91cf\u66f4\u65b0&#xff0c;\u51cf\u5c11 Copy \u7684\u6b21\u6570<\/span><br \/>\n        <span class=\"token comment\">\/\/ \u8fd9\u91cc\u7684\u5199\u9501\u662f\u5e95\u5c42\u7684 ReentrantLock \u4fdd\u8bc1\u7684&#xff0c;\u5199\u5199\u4e92\u65a5<\/span><br \/>\n        routes<span class=\"token punctuation\">.<\/span><span class=\"token function\">addAll<\/span><span class=\"token punctuation\">(<\/span>newRoutes<span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span><br \/>\n    <span class=\"token punctuation\">}<\/span><\/p>\n<p>    <span class=\"token keyword\">public<\/span> <span class=\"token class-name\">RouteConfig<\/span> <span class=\"token function\">findBestRoute<\/span><span class=\"token punctuation\">(<\/span><span class=\"token class-name\">String<\/span> path<span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span><br \/>\n        <span class=\"token comment\">\/\/ \u8bfb\u64cd\u4f5c\u5b8c\u5168\u975e\u963b\u585e&#xff0c;\u9002\u5408 QPS \u6781\u9ad8\u7684\u7f51\u5173\u73af\u5883<\/span><br \/>\n        <span class=\"token keyword\">return<\/span> routes<span class=\"token punctuation\">.<\/span><span class=\"token function\">stream<\/span><span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">)<\/span><br \/>\n                <span class=\"token punctuation\">.<\/span><span class=\"token function\">filter<\/span><span class=\"token punctuation\">(<\/span>r <span class=\"token operator\">-&gt;<\/span> r<span class=\"token punctuation\">.<\/span><span class=\"token function\">match<\/span><span class=\"token punctuation\">(<\/span>path<span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">)<\/span><br \/>\n                <span class=\"token punctuation\">.<\/span><span class=\"token function\">findFirst<\/span><span class=\"token punctuation\">(<\/span><span class=\"token punctuation\">)<\/span><br \/>\n                <span class=\"token punctuation\">.<\/span><span class=\"token function\">orElse<\/span><span class=\"token punctuation\">(<\/span><span class=\"token keyword\">null<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span><br \/>\n    <span class=\"token punctuation\">}<\/span><\/p>\n<p>    <span class=\"token keyword\">static<\/span> <span class=\"token keyword\">class<\/span> <span class=\"token class-name\">RouteConfig<\/span> <span class=\"token punctuation\">{<\/span><br \/>\n        <span class=\"token class-name\">String<\/span> path<span class=\"token punctuation\">;<\/span><br \/>\n        <span class=\"token keyword\">boolean<\/span> <span class=\"token function\">match<\/span><span class=\"token punctuation\">(<\/span><span class=\"token class-name\">String<\/span> p<span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span> <span class=\"token keyword\">return<\/span> path<span class=\"token punctuation\">.<\/span><span class=\"token function\">equals<\/span><span class=\"token punctuation\">(<\/span>p<span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span> <span class=\"token punctuation\">}<\/span><br \/>\n    <span class=\"token punctuation\">}<\/span><br \/>\n<span class=\"token punctuation\">}<\/span><\/p>\n<hr \/>\n<h4>&#x1f30d;&#x1f4c8; \u7b2c\u4e09\u7ae0&#xff1a;\u7ef4\u5ea6\u5bf9\u6bd4\u2014\u2014CopyOnWriteArrayList vs. ConcurrentHashMap<\/h4>\n<p>\u8fd9\u662f\u9762\u8bd5\u548c\u67b6\u6784\u9009\u578b\u4e2d\u6700\u5e38\u89c1\u7684\u7ea0\u7ed3\u3002\u4e24\u8005\u90fd\u662f\u7ebf\u7a0b\u5b89\u5168\u7684&#xff0c;\u6211\u8be5\u9009\u8c01&#xff1f;<\/p>\n<h5>&#x1f4cf;\u2696\ufe0f 3.1 \u9501\u7684\u7c92\u5ea6\u535a\u5f08<\/h5>\n<ul>\n<li>COWAL&#xff1a;\u5168\u5c40\u9501\u5199\u64cd\u4f5c\u3002\u65e0\u8bba\u4f60\u4fee\u6539\u54ea\u4e2a\u4f4d\u7f6e&#xff0c;\u6574\u4e2a\u6570\u7ec4\u90fd\u8981\u590d\u5236\u3002<\/li>\n<li>ConcurrentHashMap (CHM)&#xff1a;\u9501\u6876&#xff08;Node\/Segment&#xff09;\u3002\u5728 JDK 8 \u4ee5\u540e&#xff0c;\u5b83\u901a\u8fc7 CAS \u548c synchronized \u9501\u5b9a\u6570\u7ec4\u7684\u67d0\u4e2a\u9996\u8282\u70b9\u3002\u8fd9\u610f\u5473\u7740\u4e24\u4e2a\u7ebf\u7a0b\u4fee\u6539 Map \u7684\u4e0d\u540c\u4f4d\u7f6e&#xff0c;\u662f\u53ef\u4ee5\u5b8c\u5168\u5e76\u884c\u7684\u3002<\/li>\n<\/ul>\n<h5>&#x1f4c9;&#x1f3b2; 3.2 \u8bfb\u6027\u80fd\u7684\u5dee\u5f02<\/h5>\n<ul>\n<li>COWAL&#xff1a;\u8bfb\u64cd\u4f5c\u662f\u771f\u6b63\u7684\u201c\u65e0\u9501\u201d\u3002<\/li>\n<li>CHM&#xff1a;\u8bfb\u64cd\u4f5c\u5927\u90e8\u5206\u60c5\u51b5\u4e0b\u662f\u65e0\u9501\u7684&#xff08;\u901a\u8fc7 volatile \u4fdd\u8bc1&#xff09;&#xff0c;\u4f46\u5f53\u54c8\u5e0c\u51b2\u7a81\u4e25\u91cd\u5bfc\u81f4\u94fe\u8868\u8fc7\u957f\u6216\u7ea2\u9ed1\u6811\u8f6c\u6362\u65f6&#xff0c;\u8bfb\u53d6\u6548\u7387\u4f1a\u53d7\u54c8\u5e0c\u8ba1\u7b97\u548c\u904d\u5386\u7684\u5f71\u54cd\u3002<\/li>\n<\/ul>\n<h5>&#x1f522;\u26a1 3.3 \u8fed\u4ee3\u5668\u8bed\u4e49\u7684\u4e0d\u540c<\/h5>\n<ul>\n<li>COWAL&#xff1a;\u63d0\u4f9b\u201c\u5feb\u7167\u201d\u8fed\u4ee3\u5668&#xff0c;\u4e0d\u4f1a\u629b\u51fa\u5f02\u5e38\u3002<\/li>\n<li>CHM&#xff1a;\u63d0\u4f9b\u201c\u5f31\u4e00\u81f4\u6027\u201d\u8fed\u4ee3\u5668\u3002\u5728\u904d\u5386\u8fc7\u7a0b\u4e2d&#xff0c;\u5982\u679c\u4f60\u4fee\u6539\u4e86 Map&#xff0c;\u4f60\u53ef\u80fd\u4f1a\u770b\u5230\u4fee\u6539\u540e\u7684\u7ed3\u679c&#xff0c;\u4e5f\u53ef\u80fd\u770b\u4e0d\u5230\u3002<\/li>\n<\/ul>\n<hr \/>\n<h5>&#x1f4bb;&#x1f680; \u9009\u578b\u903b\u8f91\u4ee3\u7801\u793a\u4f8b<\/h5>\n<p><span class=\"token keyword\">public<\/span> <span class=\"token keyword\">class<\/span> <span class=\"token class-name\">ContainerSelector<\/span> <span class=\"token punctuation\">{<\/span><br \/>\n    <span class=\"token keyword\">public<\/span> <span class=\"token keyword\">void<\/span> <span class=\"token function\">choose<\/span><span class=\"token punctuation\">(<\/span><span class=\"token class-name\">String<\/span> scenario<span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span><br \/>\n        <span class=\"token keyword\">if<\/span> <span class=\"token punctuation\">(<\/span><span class=\"token string\">&#034;LIST_TRAVERSAL&#034;<\/span><span class=\"token punctuation\">.<\/span><span class=\"token function\">equals<\/span><span class=\"token punctuation\">(<\/span>scenario<span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span><br \/>\n            <span class=\"token comment\">\/\/ \u9700\u8981\u9891\u7e41\u904d\u5386\u6574\u4e2a\u5217\u8868&#xff0c;\u4e14\u5199\u64cd\u4f5c\u6781\u5c11<\/span><br \/>\n            <span class=\"token class-name\">System<\/span><span class=\"token punctuation\">.<\/span>out<span class=\"token punctuation\">.<\/span><span class=\"token function\">println<\/span><span class=\"token punctuation\">(<\/span><span class=\"token string\">&#034;\u2705 \u9009 CopyOnWriteArrayList&#034;<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span><br \/>\n        <span class=\"token punctuation\">}<\/span> <span class=\"token keyword\">else<\/span> <span class=\"token keyword\">if<\/span> <span class=\"token punctuation\">(<\/span><span class=\"token string\">&#034;KEY_VALUE_LOOKUP&#034;<\/span><span class=\"token punctuation\">.<\/span><span class=\"token function\">equals<\/span><span class=\"token punctuation\">(<\/span>scenario<span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span><br \/>\n            <span class=\"token comment\">\/\/ \u9700\u8981\u901a\u8fc7\u7279\u5b9a\u7684 Key \u9ad8\u6548\u67e5\u627e<\/span><br \/>\n            <span class=\"token class-name\">System<\/span><span class=\"token punctuation\">.<\/span>out<span class=\"token punctuation\">.<\/span><span class=\"token function\">println<\/span><span class=\"token punctuation\">(<\/span><span class=\"token string\">&#034;\u2705 \u9009 ConcurrentHashMap&#034;<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span><br \/>\n        <span class=\"token punctuation\">}<\/span> <span class=\"token keyword\">else<\/span> <span class=\"token keyword\">if<\/span> <span class=\"token punctuation\">(<\/span><span class=\"token string\">&#034;FREQUENT_WRITE&#034;<\/span><span class=\"token punctuation\">.<\/span><span class=\"token function\">equals<\/span><span class=\"token punctuation\">(<\/span>scenario<span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">)<\/span> <span class=\"token punctuation\">{<\/span><br \/>\n            <span class=\"token comment\">\/\/ \u5199\u64cd\u4f5c\u9891\u7e41<\/span><br \/>\n            <span class=\"token class-name\">System<\/span><span class=\"token punctuation\">.<\/span>out<span class=\"token punctuation\">.<\/span><span class=\"token function\">println<\/span><span class=\"token punctuation\">(<\/span><span class=\"token string\">&#034;\u274c \u4e25\u7981\u4f7f\u7528 COWAL&#xff0c;\u6027\u80fd\u4f1a\u5d29\u584c&#034;<\/span><span class=\"token punctuation\">)<\/span><span class=\"token punctuation\">;<\/span><br \/>\n        <span class=\"token punctuation\">}<\/span><br \/>\n    <span class=\"token punctuation\">}<\/span><br \/>\n<span class=\"token punctuation\">}<\/span><\/p>\n<hr \/>\n<h4>\u26a0\ufe0f&#x1f4c9; \u7b2c\u56db\u7ae0&#xff1a;\u9634\u6697\u9762\u2014\u2014CopyOnWriteArrayList \u7684\u6027\u80fd\u9677\u9631\u4e0e\u4ee3\u4ef7<\/h4>\n<p>\u5982\u679c\u4f60\u7684\u7cfb\u7edf\u5728\u5f15\u5165 COWAL \u540e\u7a81\u7136\u53d8\u6162\u6216\u9891\u7e41 OOM&#xff0c;\u591a\u534a\u662f\u8e29\u5230\u4e86\u4ee5\u4e0b\u5751\u3002<\/p>\n<h5>&#x1f9ec;&#x1f9e9; 4.1 \u5185\u5b58\u7206\u70b8&#xff08;Memory Overhead&#xff09;<\/h5>\n<p>\u7531\u4e8e\u5199\u64cd\u4f5c\u662f\u590d\u5236\u6570\u7ec4&#xff0c;\u5728\u6267\u884c Arrays.copyOf \u7684\u77ac\u95f4&#xff0c;\u5185\u5b58\u4e2d\u4f1a\u540c\u65f6\u5b58\u5728\u4e24\u4efd\u6570\u7ec4\u3002\u5982\u679c\u6570\u7ec4\u5927\u5c0f\u4e3a 100MB&#xff0c;\u90a3\u4e48\u5728\u90a3\u4e00\u523b\u4f60\u7684\u5806\u5185\u5b58\u6d88\u8017\u4f1a\u6fc0\u589e\u5230 200MB\u3002\u5982\u679c\u5185\u5b58\u4f59\u91cf\u4e0d\u8db3&#xff0c;\u4f1a\u5bfc\u81f4\u9891\u7e41\u7684 GC \u505c\u987f&#xff0c;\u751a\u81f3 OOM\u3002<\/p>\n<h5>&#x1f6e1;\ufe0f\u2696\ufe0f 4.2 \u6570\u636e\u7684\u201c\u5ef6\u8fdf\u53ef\u89c1\u201d<\/h5>\n<p>\u5982\u679c\u4f60\u5728\u7ebf\u7a0b A \u4e2d add(element)&#xff0c;\u5728\u7ebf\u7a0b B \u4e2d\u7acb\u523b get(size-1)&#xff0c;\u4f60\u53ef\u80fd\u62ff\u4e0d\u5230\u6700\u65b0\u7684\u6570\u636e\u3002\u8fd9\u5c31\u662f\u6700\u7ec8\u4e00\u81f4\u6027\u7684\u5c40\u9650\u3002\u5728\u9700\u8981\u201c\u5f3a\u5b9e\u65f6\u4e00\u81f4\u6027\u201d&#xff08;\u5373\u5199\u5b8c\u5fc5\u987b\u7acb\u523b\u8bfb\u5230&#xff09;\u7684\u91d1\u878d\u8d26\u52a1\u573a\u666f\u4e0b&#xff0c;COWAL \u662f\u6781\u5176\u5371\u9669\u7684\u3002<\/p>\n<h5>&#x1f504;&#x1f9f1; 4.3 \u5199\u6027\u80fd\u7684\u65ad\u5d16\u5f0f\u4e0b\u8dcc<\/h5>\n<p>COWAL \u7684\u5199\u64cd\u4f5c\u6d89\u53ca ReentrantLock \u52a0\u9501\u3001\u6570\u7ec4\u590d\u5236\u3001\u65b0\u5f15\u7528\u8d4b\u503c\u3002\u5176\u590d\u6742\u5ea6\u662f <span class=\"katex--inline\"><span class=\"katex\"><span class=\"katex-mathml\"><\/p>\n<p>        O<\/p>\n<p>        (<\/p>\n<p>        n<\/p>\n<p>        )<\/p>\n<p>       O(n)<\/p>\n<p>    <\/span><span class=\"katex-html\"><span class=\"base\"><span class=\"strut\" style=\"height: 1em;vertical-align: -0.25em\"><\/span><span class=\"mord mathnormal\" style=\"margin-right: 0.0278em\">O<\/span><span class=\"mopen\">(<\/span><span class=\"mord mathnormal\">n<\/span><span class=\"mclose\">)<\/span><\/span><\/span><\/span><\/span>\u3002\u968f\u7740\u5143\u7d20\u6570\u91cf\u7684\u589e\u52a0&#xff0c;\u5199\u64cd\u4f5c\u7684\u8017\u65f6\u5448\u7ebf\u6027\u589e\u957f\u3002\u5728\u6d77\u91cf\u5199\u7684\u573a\u666f\u4e0b&#xff0c;\u5b83\u7684\u8868\u73b0\u751a\u81f3\u4e0d\u5982\u540c\u6b65\u7684 Vector\u3002<\/p>\n<hr \/>\n<h4>&#x1f31f;&#x1f3af; \u7b2c\u4e94\u7ae0&#xff1a;\u603b\u7ed3\u4e0e\u9009\u578b\u6307\u5357\u2014\u2014\u5982\u4f55\u4f18\u96c5\u5730\u9009\u62e9\u5e76\u53d1\u5bb9\u5668&#xff1f;<\/h4>\n<p>CopyOnWriteArrayList \u662f Java \u5e76\u53d1\u5305\u4e2d\u4e00\u6735\u201c\u504f\u6fc0\u201d\u7684\u5947\u8469\u3002\u5b83\u4e0d\u8ffd\u6c42\u5747\u8861&#xff0c;\u5b83\u8ffd\u6c42\u7684\u662f\u5728\u7279\u5b9a\u573a\u666f\u4e0b\u7684\u6781\u81f4\u3002<\/p>\n<h5>&#x1f9ec;&#x1f9e9; \u67b6\u6784\u5e08\u603b\u7ed3&#xff1a;<\/h5>\n<li>\u8bfb\u591a\u5199\u5c11\u662f\u524d\u63d0&#xff1a;\u5199\u64cd\u4f5c\u7684\u9891\u7387\u6700\u597d\u662f\u6309\u5c0f\u65f6\u751a\u81f3\u6309\u5929\u8ba1\u7b97&#xff08;\u5982\u767d\u540d\u5355\u66f4\u65b0&#xff09;\u3002<\/li>\n<li>\u6570\u636e\u91cf\u7ea7\u8981\u514b\u5236&#xff1a;\u6700\u597d\u63a7\u5236\u5728\u51e0\u5343\u4e2a\u5143\u7d20\u4ee5\u5185&#xff0c;\u907f\u514d\u5185\u5b58\u590d\u5236\u5e26\u6765\u7684 GC \u51b2\u51fb\u3002<\/li>\n<li>\u4e0d\u60e7\u6015\u5ef6\u8fdf&#xff1a;\u4e1a\u52a1\u903b\u8f91\u80fd\u591f\u5bb9\u5fcd\u6beb\u79d2\u7ea7\u7684\u914d\u7f6e\u751f\u6548\u5ef6\u8fdf\u3002<\/li>\n<li>\u904d\u5386\u4f18\u5148&#xff1a;\u5982\u679c\u4f60\u7684\u4e1a\u52a1\u4ee3\u7801\u4e2d\u5145\u6ee1\u4e86\u5bf9\u96c6\u5408\u7684 for-each \u904d\u5386&#xff0c;COWAL \u5e26\u6765\u7684\u65e0\u9501\u904d\u5386\u4f53\u9a8c\u5c06\u662f\u65e0\u4e0e\u4f26\u6bd4\u7684\u3002<\/li>\n<p>\u7ed3\u8bed&#xff1a;\u52a0\u9501\u662f\u4e3a\u4e86\u5b89\u5168&#xff0c;\u800c\u65e0\u9501\u662f\u4e3a\u4e86\u6027\u80fd\u3002CopyOnWriteArrayList \u901a\u8fc7\u727a\u7272\u7a7a\u95f4\u7684\u201c\u5927\u5ea6\u201d&#xff0c;\u6362\u53d6\u4e86\u65f6\u95f4\u4e0a\u7684\u201c\u6177\u6168\u201d\u3002\u7406\u89e3\u5b83\u7684\u727a\u7272&#xff0c;\u624d\u80fd\u7528\u597d\u5b83\u7684\u6177\u6168\u3002<\/p>\n<hr \/>\n<p>&#x1f525; \u89c9\u5f97\u8fd9\u7bc7\u6df1\u5ea6\u89e3\u6790\u5bf9\u4f60\u6709\u5e2e\u52a9&#xff1f;\u522b\u5fd8\u4e86\u70b9\u8d5e\u3001\u6536\u85cf\u3001\u5173\u6ce8\u4e09\u8fde\u652f\u6301\u4e00\u4e0b&#xff01; &#x1f4ac; \u4e92\u52a8\u8bdd\u9898&#xff1a;\u4f60\u5728\u751f\u4ea7\u73af\u5883\u4e2d\u4f7f\u7528\u8fc7 COWAL \u5417&#xff1f;\u4f60\u66fe\u56e0\u4e3a\u5b83\u7684\u5199\u64cd\u4f5c\u6162\u6216\u8005\u5185\u5b58\u5360\u7528\u5403\u8fc7\u4e8f\u5417&#xff1f;\u6b22\u8fce\u5728\u8bc4\u8bba\u533a\u5206\u4eab\u4f60\u7684\u5b9e\u6218\u6559\u8bad&#xff01;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u6587\u7ae0\u76ee\u5f55&#x1f3af;&#x1f525; \u7ebf\u7a0b\u5b89\u5168\u96c6\u5408&#xff1a;CopyOnWriteArrayList \u7684\u9002\u7528\u573a\u666f\u4e0e\u6027\u80fd\u4ee3\u4ef7&#x1f31f;&#x1f30d; \u5f15\u8a00&#xff1a;\u5e76\u53d1\u5bb9\u5668\u7684\u201c\u4e2d\u5eb8\u4e4b\u9053\u201d&#x1f4ca;&#x1f4cb; \u7b2c\u4e00\u7ae0&#xff1a;\u5e95\u5c42\u539f\u7406\u2014\u2014\u4e3a\u4ec0\u4e48\u8bfb\u591a\u5199\u5c11\u573a\u666f\u975e\u5b83\u4e0d\u53ef&#xff1f;&#x1f9ec;&#x1f9e9; 1.1 \u201c\u5199\u65f6\u590d\u5236\u201d\u7684\u7269\u7406\u672c\u8d28&#x1f6e1;\ufe0f\u2696\ufe0f 1.2 \u4e3a\u4ec0\u4e48\u8bfb\u64cd\u4f5c\u4e0d\u9700\u8981\u9501&#xff1f;&amp;#x1f4<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[6814,6815,2763,99,61,190,4591],"topic":[],"class_list":["post-64420","post","type-post","status-publish","format-standard","hentry","category-server","tag-copyonwrite","tag-6815","tag-arraylist","tag-java","tag-61","tag-190","tag-4591"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v20.3 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>\u7ebf\u7a0b\u5b89\u5168\u96c6\u5408\uff1aCopyOnWriteArrayList 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