{"id":126,"date":"2020-04-13T07:44:24","date_gmt":"2020-04-13T07:44:24","guid":{"rendered":"http:\/\/feellikelearning.com\/?p=126"},"modified":"2020-04-13T08:07:35","modified_gmt":"2020-04-13T08:07:35","slug":"cn-a-short-introduction-to-java-reflection","status":"publish","type":"post","link":"https:\/\/feellikelearning.com\/index.php\/2020\/04\/13\/cn-a-short-introduction-to-java-reflection\/","title":{"rendered":"Java \u53cd\u5c04\u5165\u95e8 | A short introduction to Java reflection"},"content":{"rendered":"\n<p>\u53cd\u5c04\u5728Java\u662f\u4e2a\u6bd4\u8f83\u5947\u602a\u7684\u6982\u5ff5\uff0c\u80cc\u540e\u7684\u601d\u60f3\u5176\u5b9e\u5f88\u6df1\u523b\u3002\u4e00\u822c\u7a0b\u5e8f\u5305\u62ec\u7a0b\u5e8f(code)\u548c\u6570\u636e(data)\u4e24\u90e8\u5206\u3002\u5982\u679c\u4e00\u4e2a\u7a0b\u5e8f\u8ba1\u7b971+1\uff0c\u90a3\u4e481\u548c1\u662f\u6570\u636e\uff0c\u800c\u52a0\u6cd5\u8fd9\u4e2a\u64cd\u4f5c\u662fcode\uff0ccode\u662f\u7f16\u8bd1\u65f6\u5c31\u51b3\u5b9a\u7684\uff0c\u7f16\u8bd1\u540e\u5c31\u4e0d\u80fd\u518d\u66f4\u6539\uff0c\u6bd4\u5982\u8fd9\u91cc\u7684\u52a0\u6cd5\u3002\u800c\u53cd\u5c04\u8fd9\u4e2a\u6982\u5ff5\u5141\u8bb8\u4e86data\u4e5f\u53ef\u4ee5\u662fcode\u7684\u6982\u5ff5\u3002\u6bd4\u5982\u73b0\u5728\u7a0b\u5e8f\u53d8\u6210\u4e86f(1, 1)\uff0cf\u662f\u4e00\u4e2a\u672a\u77e5\u51fd\u6570\uff0c\u5b83\u4e5f\u662f&#8221;data&#8221;\uff0c\u53ef\u4ee5\u7531\u7528\u6237\u63d0\u4f9b\u3002\u7528\u6237\u63d0\u4f9b\u4e86\u4e58\u6cd5\uff0c\u90a3\u5c31\u662f\u4e58\u6cd5\uff0c\u63d0\u4f9b\u4e86\u51cf\u6cd5\uff0c\u90a3\u5c31\u662f\u51cf\u6cd5\u3002\u8fd9\u6837\u63d0\u4f9b\u4e00\u4e2a\u8ba9\u7a0b\u5e8f\u5728\u8fd0\u884c\u65f6\u4fee\u6539\u81ea\u5df1\u7684\u673a\u5236\u3002\u8fd9\u6837\u80fd\u63d0\u9ad8\u7a0b\u5e8f\u7684\u8868\u8fbe\u529b\uff0c\u4e00\u4e9bJava\u7684\u6846\u67b6\u6bd4\u5982Spring\u5c31\u5927\u91cf\u7528\u5230\u53cd\u5c04\u3002Spring\u91cc\u9762\u5f88\u591amagical\u7684\u73b0\u8c61\u5c31\u662f\u8fd9\u6837\u5b9e\u73b0\u7684\uff0c\u6bd4\u5982\u6211\u660e\u660e\u53ea\u5199\u4e86\u4e00\u4e2aclass\uff0c\u53e6\u4e00\u4e2a\u5730\u65b9\u6211\u5c31\u81ea\u52a8\u6709\u4e86\u4e00\u4e2a\u8fd9\u4e2aclass\u7684object\uff0c\u800c\u6211\u660e\u660e\u6ca1\u6709\u5728\u4efb\u4f55\u5730\u65b9\u521d\u59cb\u5316\u8fd9\u4e48\u4e00\u4e2a\u5bf9\u8c61\u3002IDE\u91cc\u9762\u81ea\u52a8\u63d0\u793a\u4e00\u4e2aclass\u91cc\u9762\u7684available methods\u5e94\u8be5\u4e5f\u662f\u7528\u5230\u4e86reflection\u3002\u5728\u5e94\u7528\u4e2d\u6709\u4e9b\u574f\u5904\u4e5f\u662f\u663e\u800c\u6613\u89c1\uff0c\u9700\u8981\u5c0f\u5fc3\u3002\u5728Java\u91cc\u9762reflection\u901f\u5ea6\u6162\u8fd8\u662f\u5176\u6b21\uff0cIDE\u5f88\u96be\u68c0\u6d4b\u5230\u4ee3\u7801\u88ab\u5f15\u7528\uff0c\u8fd8\u6709\u5f88\u591acompiler\u53ef\u4ee5\u68c0\u6d4b\u5230\u7684\u9519\u8bef\u88ab\u6f0f\u8fc7\u4e86\uff0c\u53ea\u80fd\u5728run time\u51fa\u95ee\u9898\u3002\u800c\u4e14\u5141\u8bb8\u5916\u90e8\u8f93\u5165\u4ee3\u7801\u4e5f\u5e26\u6765\u5b89\u5168\u95ee\u9898\u3002\u5f88\u591a\u7f51\u7edc\u653b\u51fb\u7684\u539f\u7406\u6bd4\u5982SQL injection\u5c31\u662f\u5229\u7528\u4e86data\u4e5f\u662fcode\u7684\u8fd9\u79cd\u7279\u6027\u3002\u5173\u4e8erefelection\u5f88\u591a\u7684\u7528\u6cd5\u4ee5\u540e\u6211\u4f1a\u518d\u5199\u3002<\/p>\n\n\n\n<p>\u672c\u6587\u901a\u8fc7\u4e00\u4e2a\u7b80\u5355\u7684Java\u4f8b\u5b50\u6765\u6f14\u793a\u4e00\u4e0bJava\u7684reflection\u3002Just get a feeling. <\/p>\n\n\n\n<p>Animal.java<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>package learn.java.reflection;\n\npublic interface Animal {\n    public void whoami();\n}\n<\/code><\/pre>\n\n\n\n<p><\/p>\n\n\n\n<p>Tiger.java<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>package learn.java.reflection;\n\npublic class Tiger implements Animal {\n    @Override\n    public void whoami() {\n        System.out.println(\"I am a tiger\");\n    }\n}\n<\/code><\/pre>\n\n\n\n<p><\/p>\n\n\n\n<p>Lion.java<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>package learn.java.reflection;\n\npublic class Lion implements Animal {\n    @Override\n    public void whoami() {\n        System.out.println(\"I am a lion\");\n    }\n}\n<\/code><\/pre>\n\n\n\n<p><\/p>\n\n\n\n<p>Zoo.java<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>package learn.java.reflection;\n\nimport java.util.Scanner;\n\npublic class Zoo {\n    public static void main(String[] args) throws ClassNotFoundException, IllegalAccessException, InstantiationException {\n        Scanner scanner = new Scanner(System.in);\n        System.out.println(\"Choose [1] for tiger, [2] for lion: \");\n        String opt = scanner.nextLine();\n        String className = null;\n        while (true) {\n            if (\"1\".equals(opt)) {\n                className = \"learn.java.reflection.Tiger\";\n                break;\n            } else if (\"2\".equals(opt)) {\n                className = \"learn.java.reflection.Lion\";\n                break;\n            } else {\n                System.out.println(\"Choose [1] for tiger, [2] for lion: \");\n                opt = scanner.nextLine();\n            }\n        }\n\n        Class cls = Class.forName(className);\n        Animal animal = (Animal) cls.newInstance();\n        animal.whoami();\n    }\n}\n<\/code><\/pre>\n\n\n\n<p>\u8fd0\u884c\u7ed3\u679c<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>Choose [1] for tiger, [2] for lion: \n1\nI am a tiger\n\nChoose [1] for tiger, [2] for lion: \n2\nI am a lion\n<\/code><\/pre>\n\n\n\n<p><\/p>\n\n\n\n<p>Zoo.java \u4e3a\u4e3b\u7a0b\u5e8f\u3002\u91cc\u9762\u7684animal\u662f\u4ec0\u4e48\u8981\u770b\u7528\u6237\u63d0\u4f9b\u7684data\u51b3\u5b9a\u800c\u4e0d\u662fcompile time\u51b3\u5b9a\u7684\u3002\u5728IDE\u91cc\u9762\uff0c\u90fd\u627e\u4e0d\u5230Lion.java\u548cTiger.java\u7684\u5f15\u7528\u3002\u56e0\u4e3a\u4ed6\u4eec\u662f\u8fd9\u6837\u88ab\u7528\u5230\u7684\uff1a<code>Class cls = Class.forName(className)<\/code>\u3002className\u8fd8\u662f\u4e2aruntime\u624d\u80fd\u77e5\u9053\u7684String\uff0c\u8fde\u4eba\u7c7b\u90fd\u4e0d\u662f\u5f88\u5bb9\u6613\u80fd\u53d1\u73b0\uff0cIDE\u80fd\u77e5\u9053\u5c31\u771f\u7684\u5b9e\u73b0\u4eba\u5de5\u667a\u80fd\u4e86\u3002<\/p>\n\n\n\n<p>\u867d\u7136\u6211\u672c\u4eba\u5e76\u4e0d\u662fReflection\u7684\u7c89\u4e1d\uff0c\u4f46\u662f\u56e0\u4e3a\u5408\u4f5c\u4e2d\u540c\u4e8b\u53ef\u80fd\u4f1a\u7528\u5230\uff0c\u6216\u8005\u516c\u53f8\u6240\u9009\u7684\u6846\u67b6\u7528\u5230\uff0c\u6bd4\u5982Spring\u4e4b\u7c7b\u4e5f\u662f\u88ab\u5e7f\u6cdb\u4f7f\u7528\uff0c\u8fd8\u662f\u5e94\u8be5\u62b1\u6709\u5f00\u653e\u7684\u5fc3\u6001\u5b66\u4e60\u5e76\u9a7e\u9a6d\u5b83\u3002<\/p>\n\n\n\n<p>\u53e6\u5916\uff0c\u672c\u6587\u63d0\u4f9b\u7684\u5c0f\u7a0b\u5e8f\u7a0b\u5e8f\u4e5f\u5305\u542b\u4e86Java\u4ece\u952e\u76d8\u8f93\u5165data\u7684\u4f8b\u5b50\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u53cd\u5c04\u5728Java\u662f\u4e2a\u6bd4\u8f83\u5947\u602a\u7684\u6982\u5ff5\uff0c\u80cc\u540e\u7684\u601d\u60f3\u5176\u5b9e\u5f88\u6df1\u523b\u3002\u4e00\u822c\u7a0b\u5e8f\u5305\u62ec\u7a0b\u5e8f(code)\u548c\u6570\u636e(data)\u4e24\u90e8\u5206\u3002\u5982\u679c\u4e00\u4e2a\u7a0b\u5e8f\u8ba1\u7b971+1\uff0c\u90a3\u4e481\u548c1\u662f\u6570\u636e\uff0c\u800c\u52a0\u6cd5\u8fd9\u4e2a\u64cd\u4f5c\u662fcode\uff0ccode\u662f\u7f16\u8bd1\u65f6\u5c31\u51b3\u5b9a\u7684\uff0c\u7f16\u8bd1\u540e\u5c31\u4e0d\u80fd\u518d\u66f4\u6539\uff0c\u6bd4\u5982\u8fd9\u91cc\u7684\u52a0\u6cd5\u3002\u800c\u53cd\u5c04\u8fd9\u4e2a\u6982\u5ff5\u5141\u8bb8\u4e86data\u4e5f\u53ef\u4ee5\u662fcode\u7684\u6982\u5ff5\u3002\u6bd4\u5982\u73b0\u5728\u7a0b\u5e8f\u53d8\u6210\u4e86f(1, 1)\uff0cf\u662f\u4e00\u4e2a\u672a\u77e5\u51fd\u6570\uff0c\u5b83\u4e5f\u662f&#8221;data&#8221;\uff0c\u53ef\u4ee5\u7531\u7528\u6237\u63d0\u4f9b\u3002\u7528\u6237\u63d0\u4f9b\u4e86\u4e58\u6cd5\uff0c\u90a3\u5c31\u662f\u4e58\u6cd5\uff0c\u63d0\u4f9b\u4e86\u51cf\u6cd5\uff0c\u90a3\u5c31\u662f\u51cf\u6cd5\u3002\u8fd9\u6837\u63d0\u4f9b\u4e00\u4e2a\u8ba9\u7a0b\u5e8f\u5728\u8fd0\u884c\u65f6\u4fee\u6539\u81ea\u5df1\u7684\u673a\u5236\u3002\u8fd9\u6837\u80fd\u63d0\u9ad8\u7a0b\u5e8f\u7684\u8868\u8fbe\u529b\uff0c\u4e00\u4e9bJava\u7684\u6846\u67b6\u6bd4\u5982Spring\u5c31\u5927\u91cf\u7528\u5230\u53cd\u5c04\u3002Spring\u91cc\u9762\u5f88\u591amagical\u7684\u73b0\u8c61\u5c31\u662f\u8fd9\u6837\u5b9e\u73b0\u7684\uff0c\u6bd4\u5982\u6211\u660e\u660e\u53ea\u5199\u4e86\u4e00\u4e2aclass\uff0c\u53e6\u4e00\u4e2a\u5730\u65b9\u6211\u5c31\u81ea\u52a8\u6709\u4e86\u4e00\u4e2a\u8fd9\u4e2aclass\u7684object\uff0c\u800c\u6211\u660e\u660e\u6ca1\u6709\u5728\u4efb\u4f55\u5730\u65b9\u521d\u59cb\u5316\u8fd9\u4e48\u4e00\u4e2a\u5bf9\u8c61\u3002IDE\u91cc\u9762\u81ea\u52a8\u63d0\u793a\u4e00\u4e2aclass\u91cc\u9762\u7684available methods\u5e94\u8be5\u4e5f\u662f\u7528\u5230\u4e86reflection\u3002\u5728\u5e94\u7528\u4e2d\u6709\u4e9b\u574f\u5904\u4e5f\u662f\u663e\u800c\u6613\u89c1\uff0c\u9700\u8981\u5c0f\u5fc3\u3002\u5728Java\u91cc\u9762reflection\u901f\u5ea6\u6162\u8fd8\u662f\u5176\u6b21\uff0cIDE\u5f88\u96be\u68c0\u6d4b\u5230\u4ee3\u7801\u88ab\u5f15\u7528\uff0c\u8fd8\u6709\u5f88\u591acompiler\u53ef\u4ee5\u68c0\u6d4b\u5230\u7684\u9519\u8bef\u88ab\u6f0f\u8fc7\u4e86\uff0c\u53ea\u80fd\u5728run time\u51fa\u95ee\u9898\u3002\u800c\u4e14\u5141\u8bb8\u5916\u90e8\u8f93\u5165\u4ee3\u7801\u4e5f\u5e26\u6765\u5b89\u5168\u95ee\u9898\u3002\u5f88\u591a\u7f51\u7edc\u653b\u51fb\u7684\u539f\u7406\u6bd4\u5982SQL injection\u5c31\u662f\u5229\u7528\u4e86data\u4e5f\u662fcode\u7684\u8fd9\u79cd\u7279\u6027\u3002\u5173\u4e8erefelection\u5f88\u591a\u7684\u7528\u6cd5\u4ee5\u540e\u6211\u4f1a\u518d\u5199\u3002 \u672c\u6587\u901a\u8fc7\u4e00\u4e2a\u7b80\u5355\u7684Java\u4f8b\u5b50\u6765\u6f14\u793a\u4e00\u4e0bJava\u7684reflection\u3002Just get a feeling. Animal.java Tiger.java Lion.java Zoo.java \u8fd0\u884c\u7ed3\u679c Zoo.java \u4e3a\u4e3b\u7a0b\u5e8f\u3002\u91cc\u9762\u7684animal\u662f\u4ec0\u4e48\u8981\u770b\u7528\u6237\u63d0\u4f9b\u7684data\u51b3\u5b9a\u800c\u4e0d\u662fcompile time\u51b3\u5b9a\u7684\u3002\u5728IDE\u91cc\u9762\uff0c\u90fd\u627e\u4e0d\u5230Lion.java\u548cTiger.java\u7684\u5f15\u7528\u3002\u56e0\u4e3a\u4ed6\u4eec\u662f\u8fd9\u6837\u88ab\u7528\u5230\u7684\uff1aClass cls = Class.forName(className)\u3002className\u8fd8\u662f\u4e2aruntime\u624d\u80fd\u77e5\u9053\u7684String\uff0c\u8fde\u4eba\u7c7b\u90fd\u4e0d\u662f\u5f88\u5bb9\u6613\u80fd\u53d1\u73b0\uff0cIDE\u80fd\u77e5\u9053\u5c31\u771f\u7684\u5b9e\u73b0\u4eba\u5de5\u667a\u80fd\u4e86\u3002 \u867d\u7136\u6211\u672c\u4eba\u5e76\u4e0d\u662fReflection\u7684\u7c89\u4e1d\uff0c\u4f46\u662f\u56e0\u4e3a\u5408\u4f5c\u4e2d\u540c\u4e8b\u53ef\u80fd\u4f1a\u7528\u5230\uff0c\u6216\u8005\u516c\u53f8\u6240\u9009\u7684\u6846\u67b6\u7528\u5230\uff0c\u6bd4\u5982Spring\u4e4b\u7c7b\u4e5f\u662f\u88ab\u5e7f\u6cdb\u4f7f\u7528\uff0c\u8fd8\u662f\u5e94\u8be5\u62b1\u6709\u5f00\u653e\u7684\u5fc3\u6001\u5b66\u4e60\u5e76\u9a7e\u9a6d\u5b83\u3002 \u53e6\u5916\uff0c\u672c\u6587\u63d0\u4f9b\u7684\u5c0f\u7a0b\u5e8f\u7a0b\u5e8f\u4e5f\u5305\u542b\u4e86Java\u4ece\u952e\u76d8\u8f93\u5165data\u7684\u4f8b\u5b50\u3002<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_mi_skip_tracking":false},"categories":[1],"tags":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v19.10 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>Java \u53cd\u5c04\u5165\u95e8 | A short introduction to Java reflection | Feel Like Learning<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/feellikelearning.com\/index.php\/2020\/04\/13\/cn-a-short-introduction-to-java-reflection\/?variant=zh-hant\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Java \u53cd\u5c04\u5165\u95e8 | A short introduction to Java reflection | Feel Like Learning\" \/>\n<meta property=\"og:description\" content=\"\u53cd\u5c04\u5728Java\u662f\u4e2a\u6bd4\u8f83\u5947\u602a\u7684\u6982\u5ff5\uff0c\u80cc\u540e\u7684\u601d\u60f3\u5176\u5b9e\u5f88\u6df1\u523b\u3002\u4e00\u822c\u7a0b\u5e8f\u5305\u62ec\u7a0b\u5e8f(code)\u548c\u6570\u636e(data)\u4e24\u90e8\u5206\u3002\u5982\u679c\u4e00\u4e2a\u7a0b\u5e8f\u8ba1\u7b971+1\uff0c\u90a3\u4e481\u548c1\u662f\u6570\u636e\uff0c\u800c\u52a0\u6cd5\u8fd9\u4e2a\u64cd\u4f5c\u662fcode\uff0ccode\u662f\u7f16\u8bd1\u65f6\u5c31\u51b3\u5b9a\u7684\uff0c\u7f16\u8bd1\u540e\u5c31\u4e0d\u80fd\u518d\u66f4\u6539\uff0c\u6bd4\u5982\u8fd9\u91cc\u7684\u52a0\u6cd5\u3002\u800c\u53cd\u5c04\u8fd9\u4e2a\u6982\u5ff5\u5141\u8bb8\u4e86data\u4e5f\u53ef\u4ee5\u662fcode\u7684\u6982\u5ff5\u3002\u6bd4\u5982\u73b0\u5728\u7a0b\u5e8f\u53d8\u6210\u4e86f(1, 1)\uff0cf\u662f\u4e00\u4e2a\u672a\u77e5\u51fd\u6570\uff0c\u5b83\u4e5f\u662f&#8221;data&#8221;\uff0c\u53ef\u4ee5\u7531\u7528\u6237\u63d0\u4f9b\u3002\u7528\u6237\u63d0\u4f9b\u4e86\u4e58\u6cd5\uff0c\u90a3\u5c31\u662f\u4e58\u6cd5\uff0c\u63d0\u4f9b\u4e86\u51cf\u6cd5\uff0c\u90a3\u5c31\u662f\u51cf\u6cd5\u3002\u8fd9\u6837\u63d0\u4f9b\u4e00\u4e2a\u8ba9\u7a0b\u5e8f\u5728\u8fd0\u884c\u65f6\u4fee\u6539\u81ea\u5df1\u7684\u673a\u5236\u3002\u8fd9\u6837\u80fd\u63d0\u9ad8\u7a0b\u5e8f\u7684\u8868\u8fbe\u529b\uff0c\u4e00\u4e9bJava\u7684\u6846\u67b6\u6bd4\u5982Spring\u5c31\u5927\u91cf\u7528\u5230\u53cd\u5c04\u3002Spring\u91cc\u9762\u5f88\u591amagical\u7684\u73b0\u8c61\u5c31\u662f\u8fd9\u6837\u5b9e\u73b0\u7684\uff0c\u6bd4\u5982\u6211\u660e\u660e\u53ea\u5199\u4e86\u4e00\u4e2aclass\uff0c\u53e6\u4e00\u4e2a\u5730\u65b9\u6211\u5c31\u81ea\u52a8\u6709\u4e86\u4e00\u4e2a\u8fd9\u4e2aclass\u7684object\uff0c\u800c\u6211\u660e\u660e\u6ca1\u6709\u5728\u4efb\u4f55\u5730\u65b9\u521d\u59cb\u5316\u8fd9\u4e48\u4e00\u4e2a\u5bf9\u8c61\u3002IDE\u91cc\u9762\u81ea\u52a8\u63d0\u793a\u4e00\u4e2aclass\u91cc\u9762\u7684available methods\u5e94\u8be5\u4e5f\u662f\u7528\u5230\u4e86reflection\u3002\u5728\u5e94\u7528\u4e2d\u6709\u4e9b\u574f\u5904\u4e5f\u662f\u663e\u800c\u6613\u89c1\uff0c\u9700\u8981\u5c0f\u5fc3\u3002\u5728Java\u91cc\u9762reflection\u901f\u5ea6\u6162\u8fd8\u662f\u5176\u6b21\uff0cIDE\u5f88\u96be\u68c0\u6d4b\u5230\u4ee3\u7801\u88ab\u5f15\u7528\uff0c\u8fd8\u6709\u5f88\u591acompiler\u53ef\u4ee5\u68c0\u6d4b\u5230\u7684\u9519\u8bef\u88ab\u6f0f\u8fc7\u4e86\uff0c\u53ea\u80fd\u5728run time\u51fa\u95ee\u9898\u3002\u800c\u4e14\u5141\u8bb8\u5916\u90e8\u8f93\u5165\u4ee3\u7801\u4e5f\u5e26\u6765\u5b89\u5168\u95ee\u9898\u3002\u5f88\u591a\u7f51\u7edc\u653b\u51fb\u7684\u539f\u7406\u6bd4\u5982SQL injection\u5c31\u662f\u5229\u7528\u4e86data\u4e5f\u662fcode\u7684\u8fd9\u79cd\u7279\u6027\u3002\u5173\u4e8erefelection\u5f88\u591a\u7684\u7528\u6cd5\u4ee5\u540e\u6211\u4f1a\u518d\u5199\u3002 \u672c\u6587\u901a\u8fc7\u4e00\u4e2a\u7b80\u5355\u7684Java\u4f8b\u5b50\u6765\u6f14\u793a\u4e00\u4e0bJava\u7684reflection\u3002Just get a feeling. Animal.java Tiger.java Lion.java Zoo.java \u8fd0\u884c\u7ed3\u679c Zoo.java \u4e3a\u4e3b\u7a0b\u5e8f\u3002\u91cc\u9762\u7684animal\u662f\u4ec0\u4e48\u8981\u770b\u7528\u6237\u63d0\u4f9b\u7684data\u51b3\u5b9a\u800c\u4e0d\u662fcompile time\u51b3\u5b9a\u7684\u3002\u5728IDE\u91cc\u9762\uff0c\u90fd\u627e\u4e0d\u5230Lion.java\u548cTiger.java\u7684\u5f15\u7528\u3002\u56e0\u4e3a\u4ed6\u4eec\u662f\u8fd9\u6837\u88ab\u7528\u5230\u7684\uff1aClass cls = Class.forName(className)\u3002className\u8fd8\u662f\u4e2aruntime\u624d\u80fd\u77e5\u9053\u7684String\uff0c\u8fde\u4eba\u7c7b\u90fd\u4e0d\u662f\u5f88\u5bb9\u6613\u80fd\u53d1\u73b0\uff0cIDE\u80fd\u77e5\u9053\u5c31\u771f\u7684\u5b9e\u73b0\u4eba\u5de5\u667a\u80fd\u4e86\u3002 \u867d\u7136\u6211\u672c\u4eba\u5e76\u4e0d\u662fReflection\u7684\u7c89\u4e1d\uff0c\u4f46\u662f\u56e0\u4e3a\u5408\u4f5c\u4e2d\u540c\u4e8b\u53ef\u80fd\u4f1a\u7528\u5230\uff0c\u6216\u8005\u516c\u53f8\u6240\u9009\u7684\u6846\u67b6\u7528\u5230\uff0c\u6bd4\u5982Spring\u4e4b\u7c7b\u4e5f\u662f\u88ab\u5e7f\u6cdb\u4f7f\u7528\uff0c\u8fd8\u662f\u5e94\u8be5\u62b1\u6709\u5f00\u653e\u7684\u5fc3\u6001\u5b66\u4e60\u5e76\u9a7e\u9a6d\u5b83\u3002 \u53e6\u5916\uff0c\u672c\u6587\u63d0\u4f9b\u7684\u5c0f\u7a0b\u5e8f\u7a0b\u5e8f\u4e5f\u5305\u542b\u4e86Java\u4ece\u952e\u76d8\u8f93\u5165data\u7684\u4f8b\u5b50\u3002\" \/>\n<meta property=\"og:url\" content=\"https:\/\/feellikelearning.com\/index.php\/2020\/04\/13\/cn-a-short-introduction-to-java-reflection\/?variant=zh-hant\" \/>\n<meta property=\"og:site_name\" content=\"Feel Like Learning\" \/>\n<meta property=\"article:published_time\" content=\"2020-04-13T07:44:24+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2020-04-13T08:07:35+00:00\" \/>\n<meta name=\"author\" content=\"feellikelearning\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"feellikelearning\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"1 minute\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\/\/feellikelearning.com\/index.php\/2020\/04\/13\/cn-a-short-introduction-to-java-reflection\/?variant=zh-hant#article\",\"isPartOf\":{\"@id\":\"https:\/\/feellikelearning.com\/index.php\/2020\/04\/13\/cn-a-short-introduction-to-java-reflection\/?variant=zh-hant\"},\"author\":{\"name\":\"feellikelearning\",\"@id\":\"https:\/\/feellikelearning.com\/#\/schema\/person\/91fb815bebebf166c217b5e3764d437a\"},\"headline\":\"Java \u53cd\u5c04\u5165\u95e8 | A short introduction to Java reflection\",\"datePublished\":\"2020-04-13T07:44:24+00:00\",\"dateModified\":\"2020-04-13T08:07:35+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\/\/feellikelearning.com\/index.php\/2020\/04\/13\/cn-a-short-introduction-to-java-reflection\/?variant=zh-hant\"},\"wordCount\":74,\"commentCount\":0,\"publisher\":{\"@id\":\"https:\/\/feellikelearning.com\/#\/schema\/person\/91fb815bebebf166c217b5e3764d437a\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"CommentAction\",\"name\":\"Comment\",\"target\":[\"https:\/\/feellikelearning.com\/index.php\/2020\/04\/13\/cn-a-short-introduction-to-java-reflection\/?variant=zh-hant#respond\"]}]},{\"@type\":\"WebPage\",\"@id\":\"https:\/\/feellikelearning.com\/index.php\/2020\/04\/13\/cn-a-short-introduction-to-java-reflection\/?variant=zh-hant\",\"url\":\"https:\/\/feellikelearning.com\/index.php\/2020\/04\/13\/cn-a-short-introduction-to-java-reflection\/?variant=zh-hant\",\"name\":\"Java \u53cd\u5c04\u5165\u95e8 | A short introduction to Java reflection | Feel Like Learning\",\"isPartOf\":{\"@id\":\"https:\/\/feellikelearning.com\/#website\"},\"datePublished\":\"2020-04-13T07:44:24+00:00\",\"dateModified\":\"2020-04-13T08:07:35+00:00\",\"breadcrumb\":{\"@id\":\"https:\/\/feellikelearning.com\/index.php\/2020\/04\/13\/cn-a-short-introduction-to-java-reflection\/?variant=zh-hant#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\/\/feellikelearning.com\/index.php\/2020\/04\/13\/cn-a-short-introduction-to-java-reflection\/?variant=zh-hant\"]}]},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\/\/feellikelearning.com\/index.php\/2020\/04\/13\/cn-a-short-introduction-to-java-reflection\/?variant=zh-hant#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\/\/feellikelearning.com\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Java \u53cd\u5c04\u5165\u95e8 | A short introduction to Java reflection\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\/\/feellikelearning.com\/#website\",\"url\":\"https:\/\/feellikelearning.com\/\",\"name\":\"Feel Like Learning\",\"description\":\"\u7a0b\u5e8f\uff5c\u751f\u6d3b\uff5c\u5b66\u5230\u5c31\u662f\u8d5a\u5230\",\"publisher\":{\"@id\":\"https:\/\/feellikelearning.com\/#\/schema\/person\/91fb815bebebf166c217b5e3764d437a\"},\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\/\/feellikelearning.com\/?s={search_term_string}\"},\"query-input\":\"required name=search_term_string\"}],\"inLanguage\":\"en-US\"},{\"@type\":[\"Person\",\"Organization\"],\"@id\":\"https:\/\/feellikelearning.com\/#\/schema\/person\/91fb815bebebf166c217b5e3764d437a\",\"name\":\"feellikelearning\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\/\/feellikelearning.com\/#\/schema\/person\/image\/\",\"url\":\"https:\/\/secure.gravatar.com\/avatar\/72a1e86e9dcb0332e88bd7d54fd36c28?s=96&d=mm&r=g\",\"contentUrl\":\"https:\/\/secure.gravatar.com\/avatar\/72a1e86e9dcb0332e88bd7d54fd36c28?s=96&d=mm&r=g\",\"caption\":\"feellikelearning\"},\"logo\":{\"@id\":\"https:\/\/feellikelearning.com\/#\/schema\/person\/image\/\"},\"url\":\"https:\/\/feellikelearning.com\/index.php\/author\/feellikelearning\/\"}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"Java \u53cd\u5c04\u5165\u95e8 | A short introduction to Java reflection | Feel Like Learning","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/feellikelearning.com\/index.php\/2020\/04\/13\/cn-a-short-introduction-to-java-reflection\/?variant=zh-hant","og_locale":"en_US","og_type":"article","og_title":"Java \u53cd\u5c04\u5165\u95e8 | A short introduction to Java reflection | Feel Like Learning","og_description":"\u53cd\u5c04\u5728Java\u662f\u4e2a\u6bd4\u8f83\u5947\u602a\u7684\u6982\u5ff5\uff0c\u80cc\u540e\u7684\u601d\u60f3\u5176\u5b9e\u5f88\u6df1\u523b\u3002\u4e00\u822c\u7a0b\u5e8f\u5305\u62ec\u7a0b\u5e8f(code)\u548c\u6570\u636e(data)\u4e24\u90e8\u5206\u3002\u5982\u679c\u4e00\u4e2a\u7a0b\u5e8f\u8ba1\u7b971+1\uff0c\u90a3\u4e481\u548c1\u662f\u6570\u636e\uff0c\u800c\u52a0\u6cd5\u8fd9\u4e2a\u64cd\u4f5c\u662fcode\uff0ccode\u662f\u7f16\u8bd1\u65f6\u5c31\u51b3\u5b9a\u7684\uff0c\u7f16\u8bd1\u540e\u5c31\u4e0d\u80fd\u518d\u66f4\u6539\uff0c\u6bd4\u5982\u8fd9\u91cc\u7684\u52a0\u6cd5\u3002\u800c\u53cd\u5c04\u8fd9\u4e2a\u6982\u5ff5\u5141\u8bb8\u4e86data\u4e5f\u53ef\u4ee5\u662fcode\u7684\u6982\u5ff5\u3002\u6bd4\u5982\u73b0\u5728\u7a0b\u5e8f\u53d8\u6210\u4e86f(1, 1)\uff0cf\u662f\u4e00\u4e2a\u672a\u77e5\u51fd\u6570\uff0c\u5b83\u4e5f\u662f&#8221;data&#8221;\uff0c\u53ef\u4ee5\u7531\u7528\u6237\u63d0\u4f9b\u3002\u7528\u6237\u63d0\u4f9b\u4e86\u4e58\u6cd5\uff0c\u90a3\u5c31\u662f\u4e58\u6cd5\uff0c\u63d0\u4f9b\u4e86\u51cf\u6cd5\uff0c\u90a3\u5c31\u662f\u51cf\u6cd5\u3002\u8fd9\u6837\u63d0\u4f9b\u4e00\u4e2a\u8ba9\u7a0b\u5e8f\u5728\u8fd0\u884c\u65f6\u4fee\u6539\u81ea\u5df1\u7684\u673a\u5236\u3002\u8fd9\u6837\u80fd\u63d0\u9ad8\u7a0b\u5e8f\u7684\u8868\u8fbe\u529b\uff0c\u4e00\u4e9bJava\u7684\u6846\u67b6\u6bd4\u5982Spring\u5c31\u5927\u91cf\u7528\u5230\u53cd\u5c04\u3002Spring\u91cc\u9762\u5f88\u591amagical\u7684\u73b0\u8c61\u5c31\u662f\u8fd9\u6837\u5b9e\u73b0\u7684\uff0c\u6bd4\u5982\u6211\u660e\u660e\u53ea\u5199\u4e86\u4e00\u4e2aclass\uff0c\u53e6\u4e00\u4e2a\u5730\u65b9\u6211\u5c31\u81ea\u52a8\u6709\u4e86\u4e00\u4e2a\u8fd9\u4e2aclass\u7684object\uff0c\u800c\u6211\u660e\u660e\u6ca1\u6709\u5728\u4efb\u4f55\u5730\u65b9\u521d\u59cb\u5316\u8fd9\u4e48\u4e00\u4e2a\u5bf9\u8c61\u3002IDE\u91cc\u9762\u81ea\u52a8\u63d0\u793a\u4e00\u4e2aclass\u91cc\u9762\u7684available methods\u5e94\u8be5\u4e5f\u662f\u7528\u5230\u4e86reflection\u3002\u5728\u5e94\u7528\u4e2d\u6709\u4e9b\u574f\u5904\u4e5f\u662f\u663e\u800c\u6613\u89c1\uff0c\u9700\u8981\u5c0f\u5fc3\u3002\u5728Java\u91cc\u9762reflection\u901f\u5ea6\u6162\u8fd8\u662f\u5176\u6b21\uff0cIDE\u5f88\u96be\u68c0\u6d4b\u5230\u4ee3\u7801\u88ab\u5f15\u7528\uff0c\u8fd8\u6709\u5f88\u591acompiler\u53ef\u4ee5\u68c0\u6d4b\u5230\u7684\u9519\u8bef\u88ab\u6f0f\u8fc7\u4e86\uff0c\u53ea\u80fd\u5728run time\u51fa\u95ee\u9898\u3002\u800c\u4e14\u5141\u8bb8\u5916\u90e8\u8f93\u5165\u4ee3\u7801\u4e5f\u5e26\u6765\u5b89\u5168\u95ee\u9898\u3002\u5f88\u591a\u7f51\u7edc\u653b\u51fb\u7684\u539f\u7406\u6bd4\u5982SQL injection\u5c31\u662f\u5229\u7528\u4e86data\u4e5f\u662fcode\u7684\u8fd9\u79cd\u7279\u6027\u3002\u5173\u4e8erefelection\u5f88\u591a\u7684\u7528\u6cd5\u4ee5\u540e\u6211\u4f1a\u518d\u5199\u3002 \u672c\u6587\u901a\u8fc7\u4e00\u4e2a\u7b80\u5355\u7684Java\u4f8b\u5b50\u6765\u6f14\u793a\u4e00\u4e0bJava\u7684reflection\u3002Just get a feeling. Animal.java Tiger.java Lion.java Zoo.java \u8fd0\u884c\u7ed3\u679c Zoo.java \u4e3a\u4e3b\u7a0b\u5e8f\u3002\u91cc\u9762\u7684animal\u662f\u4ec0\u4e48\u8981\u770b\u7528\u6237\u63d0\u4f9b\u7684data\u51b3\u5b9a\u800c\u4e0d\u662fcompile time\u51b3\u5b9a\u7684\u3002\u5728IDE\u91cc\u9762\uff0c\u90fd\u627e\u4e0d\u5230Lion.java\u548cTiger.java\u7684\u5f15\u7528\u3002\u56e0\u4e3a\u4ed6\u4eec\u662f\u8fd9\u6837\u88ab\u7528\u5230\u7684\uff1aClass cls = Class.forName(className)\u3002className\u8fd8\u662f\u4e2aruntime\u624d\u80fd\u77e5\u9053\u7684String\uff0c\u8fde\u4eba\u7c7b\u90fd\u4e0d\u662f\u5f88\u5bb9\u6613\u80fd\u53d1\u73b0\uff0cIDE\u80fd\u77e5\u9053\u5c31\u771f\u7684\u5b9e\u73b0\u4eba\u5de5\u667a\u80fd\u4e86\u3002 \u867d\u7136\u6211\u672c\u4eba\u5e76\u4e0d\u662fReflection\u7684\u7c89\u4e1d\uff0c\u4f46\u662f\u56e0\u4e3a\u5408\u4f5c\u4e2d\u540c\u4e8b\u53ef\u80fd\u4f1a\u7528\u5230\uff0c\u6216\u8005\u516c\u53f8\u6240\u9009\u7684\u6846\u67b6\u7528\u5230\uff0c\u6bd4\u5982Spring\u4e4b\u7c7b\u4e5f\u662f\u88ab\u5e7f\u6cdb\u4f7f\u7528\uff0c\u8fd8\u662f\u5e94\u8be5\u62b1\u6709\u5f00\u653e\u7684\u5fc3\u6001\u5b66\u4e60\u5e76\u9a7e\u9a6d\u5b83\u3002 \u53e6\u5916\uff0c\u672c\u6587\u63d0\u4f9b\u7684\u5c0f\u7a0b\u5e8f\u7a0b\u5e8f\u4e5f\u5305\u542b\u4e86Java\u4ece\u952e\u76d8\u8f93\u5165data\u7684\u4f8b\u5b50\u3002","og_url":"https:\/\/feellikelearning.com\/index.php\/2020\/04\/13\/cn-a-short-introduction-to-java-reflection\/?variant=zh-hant","og_site_name":"Feel Like Learning","article_published_time":"2020-04-13T07:44:24+00:00","article_modified_time":"2020-04-13T08:07:35+00:00","author":"feellikelearning","twitter_card":"summary_large_image","twitter_misc":{"Written by":"feellikelearning","Est. reading time":"1 minute"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"Article","@id":"https:\/\/feellikelearning.com\/index.php\/2020\/04\/13\/cn-a-short-introduction-to-java-reflection\/?variant=zh-hant#article","isPartOf":{"@id":"https:\/\/feellikelearning.com\/index.php\/2020\/04\/13\/cn-a-short-introduction-to-java-reflection\/?variant=zh-hant"},"author":{"name":"feellikelearning","@id":"https:\/\/feellikelearning.com\/#\/schema\/person\/91fb815bebebf166c217b5e3764d437a"},"headline":"Java \u53cd\u5c04\u5165\u95e8 | A short introduction to Java reflection","datePublished":"2020-04-13T07:44:24+00:00","dateModified":"2020-04-13T08:07:35+00:00","mainEntityOfPage":{"@id":"https:\/\/feellikelearning.com\/index.php\/2020\/04\/13\/cn-a-short-introduction-to-java-reflection\/?variant=zh-hant"},"wordCount":74,"commentCount":0,"publisher":{"@id":"https:\/\/feellikelearning.com\/#\/schema\/person\/91fb815bebebf166c217b5e3764d437a"},"inLanguage":"en-US","potentialAction":[{"@type":"CommentAction","name":"Comment","target":["https:\/\/feellikelearning.com\/index.php\/2020\/04\/13\/cn-a-short-introduction-to-java-reflection\/?variant=zh-hant#respond"]}]},{"@type":"WebPage","@id":"https:\/\/feellikelearning.com\/index.php\/2020\/04\/13\/cn-a-short-introduction-to-java-reflection\/?variant=zh-hant","url":"https:\/\/feellikelearning.com\/index.php\/2020\/04\/13\/cn-a-short-introduction-to-java-reflection\/?variant=zh-hant","name":"Java \u53cd\u5c04\u5165\u95e8 | A short introduction to Java reflection | Feel Like Learning","isPartOf":{"@id":"https:\/\/feellikelearning.com\/#website"},"datePublished":"2020-04-13T07:44:24+00:00","dateModified":"2020-04-13T08:07:35+00:00","breadcrumb":{"@id":"https:\/\/feellikelearning.com\/index.php\/2020\/04\/13\/cn-a-short-introduction-to-java-reflection\/?variant=zh-hant#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/feellikelearning.com\/index.php\/2020\/04\/13\/cn-a-short-introduction-to-java-reflection\/?variant=zh-hant"]}]},{"@type":"BreadcrumbList","@id":"https:\/\/feellikelearning.com\/index.php\/2020\/04\/13\/cn-a-short-introduction-to-java-reflection\/?variant=zh-hant#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/feellikelearning.com\/"},{"@type":"ListItem","position":2,"name":"Java \u53cd\u5c04\u5165\u95e8 | A short introduction to Java reflection"}]},{"@type":"WebSite","@id":"https:\/\/feellikelearning.com\/#website","url":"https:\/\/feellikelearning.com\/","name":"Feel Like Learning","description":"\u7a0b\u5e8f\uff5c\u751f\u6d3b\uff5c\u5b66\u5230\u5c31\u662f\u8d5a\u5230","publisher":{"@id":"https:\/\/feellikelearning.com\/#\/schema\/person\/91fb815bebebf166c217b5e3764d437a"},"potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/feellikelearning.com\/?s={search_term_string}"},"query-input":"required name=search_term_string"}],"inLanguage":"en-US"},{"@type":["Person","Organization"],"@id":"https:\/\/feellikelearning.com\/#\/schema\/person\/91fb815bebebf166c217b5e3764d437a","name":"feellikelearning","image":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/feellikelearning.com\/#\/schema\/person\/image\/","url":"https:\/\/secure.gravatar.com\/avatar\/72a1e86e9dcb0332e88bd7d54fd36c28?s=96&d=mm&r=g","contentUrl":"https:\/\/secure.gravatar.com\/avatar\/72a1e86e9dcb0332e88bd7d54fd36c28?s=96&d=mm&r=g","caption":"feellikelearning"},"logo":{"@id":"https:\/\/feellikelearning.com\/#\/schema\/person\/image\/"},"url":"https:\/\/feellikelearning.com\/index.php\/author\/feellikelearning\/"}]}},"_links":{"self":[{"href":"https:\/\/feellikelearning.com\/index.php\/wp-json\/wp\/v2\/posts\/126"}],"collection":[{"href":"https:\/\/feellikelearning.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/feellikelearning.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/feellikelearning.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/feellikelearning.com\/index.php\/wp-json\/wp\/v2\/comments?post=126"}],"version-history":[{"count":8,"href":"https:\/\/feellikelearning.com\/index.php\/wp-json\/wp\/v2\/posts\/126\/revisions"}],"predecessor-version":[{"id":137,"href":"https:\/\/feellikelearning.com\/index.php\/wp-json\/wp\/v2\/posts\/126\/revisions\/137"}],"wp:attachment":[{"href":"https:\/\/feellikelearning.com\/index.php\/wp-json\/wp\/v2\/media?parent=126"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/feellikelearning.com\/index.php\/wp-json\/wp\/v2\/categories?post=126"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/feellikelearning.com\/index.php\/wp-json\/wp\/v2\/tags?post=126"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}