Java\u53cd\u5c04\u662fJava\u8bed\u8a00\u7684\u4e00\u9879\u5f3a\u5927\u529f\u80fd\uff0c\u5141\u8bb8\u8fd0\u884c\u4e2d\u7684\u7a0b\u5e8f\u68c0\u67e5\u548c\u64cd\u4f5c\u81ea\u8eab\u7684\u7ed3\u6784\uff0c\u5305\u62ec\u7c7b\u3001\u65b9\u6cd5\u3001\u5b57\u6bb5\u548c\u6784\u9020\u65b9\u6cd5\u3002\u8fd9\u79cd\u80fd\u529b\u5bf9\u4e8e\u6784\u5efa\u7075\u6d3b\u4e14\u52a8\u6001\u7684\u5e94\u7528\u7a0b\u5e8f\uff0c\u7279\u522b\u662f\u5728\u6846\u67b6\u548c\u5e93\u4e2d\u81f3\u5173\u91cd\u8981\u3002<\/p>\n
\u53cd\u5c04\u4f7fJava\u7a0b\u5e8f\u80fd\u591f\u5728\u8fd0\u884c\u65f6\u52a8\u6001\u68c0\u67e5\u548c\u4fee\u6539\u7c7b\u53ca\u5bf9\u8c61\u7684\u5c5e\u6027\u3001\u65b9\u6cd5\u548c\u6784\u9020\u65b9\u6cd5\u3002\u901a\u8fc7\u8bbf\u95eejava.lang.Class\u5bf9\u8c61\uff0c\u5f00\u53d1\u8005\u53ef\u4ee5\u83b7\u53d6\u7c7b\u7684\u5143\u6570\u636e\uff0c\u5e76\u6267\u884c\u8bf8\u5982\u8c03\u7528\u65b9\u6cd5\u6216\u8bbf\u95ee\u5b57\u6bb5\u7b49\u64cd\u4f5c\u3002<\/p>\n
\u53cd\u5c04\u5728\u4ee5\u4e0b\u573a\u666f\u4e2d\u5e7f\u6cdb\u5e94\u7528\uff1a<\/p>\n
Java\u865a\u62df\u673a\uff08JVM\uff09\u901a\u8fc7\u4ee5\u4e0b\u6b65\u9aa4\u52a0\u8f7d\u7c7b\uff1a<\/p>\n
Class\u5bf9\u8c61\u662f\u53cd\u5c04\u7684\u5165\u53e3\uff0c\u63d0\u4f9b\u5bf9\u7c7b\u7ed3\u6784\uff08\u5305\u62ec\u5b57\u6bb5\u3001\u65b9\u6cd5\u548c\u6784\u9020\u65b9\u6cd5\uff09\u7684\u8bbf\u95ee\u3002<\/p>\n
\u83b7\u53d6Class\u5bf9\u8c61\u7684\u4e09\u79cd\u4e3b\u8981\u65b9\u5f0f\uff1a<\/p>\n
<\/code><\/p>\n\n\nClass<?> clazz = Class.forName(“java.lang.String”);<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/li>\n- \u4f7f\u7528.class\u8bed\u6cd5<\/strong>\uff1a\u76f4\u63a5\u901a\u8fc7\u7c7b\u540d\u5f15\u7528\u7c7b\u3002\n\n\njava<\/div>\n\n\n<\/div>\n<\/div>\n<\/div>\n
<\/code><\/p>\n\n\nClass<?> clazz = String.class;<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/li>\n- \u4f7f\u7528getClass()<\/strong>\uff1a\u4ece\u5b9e\u4f8b\u4e2d\u83b7\u53d6Class\u5bf9\u8c61\u3002\n\n\njava<\/div>\n\n\n<\/div>\n<\/div>\n<\/div>\n
<\/code><\/p>\n\n\nString str = “example”;<\/div>\nClass<?> clazz = str.getClass();<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/li>\n<\/ol>\n\u8bbf\u95ee\u7c7b\u7ec4\u4ef6<\/h3>\n
java.lang.reflect\u5305\u63d0\u4f9b\u4e86Field\u3001Method\u548cConstructor\u7c7b\u6765\u64cd\u4f5c\u7c7b\u7ec4\u4ef6\uff1a<\/p>\n
\n- \u5b57\u6bb5<\/strong>\uff1a\u4f7f\u7528getField\u6216getDeclaredField\u5206\u522b\u8bbf\u95ee\u516c\u5171\u5b57\u6bb5\u6216\u6240\u6709\u5b57\u6bb5\u3002<\/li>\n
- \u65b9\u6cd5<\/strong>\uff1a\u4f7f\u7528getMethod\u6216getDeclaredMethod\u5206\u522b\u83b7\u53d6\u516c\u5171\u65b9\u6cd5\u6216\u6240\u6709\u65b9\u6cd5\u3002<\/li>\n
- \u6784\u9020\u65b9\u6cd5<\/strong>\uff1a\u4f7f\u7528getConstructor\u6216getDeclaredConstructor\u5206\u522b\u8bbf\u95ee\u516c\u5171\u6784\u9020\u65b9\u6cd5\u6216\u6240\u6709\u6784\u9020\u65b9\u6cd5\u3002<\/li>\n<\/ul>\n
\u7ed5\u8fc7\u8bbf\u95ee\u9650\u5236<\/h3>\n
\u901a\u8fc7\u5728Field\u3001Method\u6216Constructor\u5bf9\u8c61\u4e0a\u8bbe\u7f6esetAccessible(true)\uff0c\u53cd\u5c04\u53ef\u4ee5\u7ed5\u8fc7Java\u7684\u8bbf\u95ee\u63a7\u5236\uff0c\u8bbf\u95ee\u79c1\u6709\u6210\u5458\u3002\u4f46\u5e94\u8c28\u614e\u4f7f\u7528\uff0c\u4ee5\u514d\u7834\u574f\u5c01\u88c5\u6027\u3002<\/p>\n
\u53cd\u5c04\u7684\u6027\u80fd\u8003\u8651<\/h2>\n
\u53cd\u5c04\u5e26\u6765\u6027\u80fd\u5f00\u9500\u7684\u539f\u56e0\u5305\u62ec\uff1a<\/p>\n
\n- \u52a8\u6001\u89e3\u6790<\/strong>\uff1a\u53cd\u5c04\u5728\u8fd0\u884c\u65f6\u89e3\u6790\u7c7b\u578b\uff0c\u65e0\u6cd5\u5229\u7528JVM\u4f18\u5316\uff08\u5982\u65b9\u6cd5\u5185\u8054\uff09\u3002<\/li>\n
- \u5bf9\u8c61\u6570\u7ec4\u521b\u5efa<\/strong>\uff1a\u5982Method.invoke\u4f7f\u7528\u53d8\u957f\u53c2\u6570\u6570\u7ec4\uff0c\u5bfc\u81f4\u5bf9\u8c61\u521b\u5efa\u5f00\u9500\u3002<\/li>\n
- \u81ea\u52a8\u88c5\u7bb1<\/strong>\uff1a\u5c06\u57fa\u672c\u7c7b\u578b\u4f20\u9012\u7ed9\u53cd\u5c04\u8c03\u7528\u9700\u8981\u81ea\u52a8\u88c5\u7bb1\uff0c\u589e\u52a0\u5185\u5b58\u4f7f\u7528\u3002<\/li>\n<\/ul>\n
\u7f13\u89e3\u6027\u80fd\u95ee\u9898\u7684\u65b9\u6cd5\uff1a<\/p>\n
\n- \u7f13\u5b58\u7ed3\u679c<\/strong>\uff1a\u5b58\u50a8Class\u548cMethod\u5bf9\u8c61\uff0c\u907f\u514d\u91cd\u590d\u67e5\u627e\u3002<\/li>\n
- \u9650\u5236\u4f7f\u7528<\/strong>\uff1a\u907f\u514d\u5728\u6027\u80fd\u654f\u611f\u7684\u4ee3\u7801\u8def\u5f84\u4e2d\u4f7f\u7528\u53cd\u5c04\u3002<\/li>\n
- \u4f7f\u7528\u66ff\u4ee3\u65b9\u6848<\/strong>\uff1a\u8003\u8651\u76f4\u63a5\u65b9\u6cd5\u8c03\u7528\u6216\u7f16\u8bd1\u5b57\u8282\u7801\u4ee5\u4f18\u5316\u9891\u7e41\u6267\u884c\u7684\u64cd\u4f5c\u3002<\/li>\n<\/ul>\n
\u793a\u4f8b\uff1a\u53cd\u5c04\u65b9\u6cd5\u8c03\u7528<\/h3>\n
\u4ee5\u4e0b\u793a\u4f8b\u5c55\u793a\u4e86\u5982\u4f55\u4f7f\u7528\u53cd\u5c04\u8c03\u7528\u65b9\u6cd5\uff1a<\/p>\n
\n\njava<\/div>\n\n\n<\/div>\n<\/div>\n<\/div>\n<\/code><\/p>\n\n\nimport java.lang.reflect.Method;<\/div>\n<\/div>\npublic class ReflectionExample {<\/div>\npublic static void printMessage(String message) {<\/div>\nSystem.out.println(“\u6d88\u606f\uff1a” + message);<\/div>\n}<\/div>\n<\/div>\npublic static void main(String[] args) throws Exception {<\/div>\nClass<?> clazz = Class.forName(“ReflectionExample”);<\/div>\nMethod method = clazz.getMethod(“printMessage”, String.class);<\/div>\nmethod.invoke(null, “\u4f60\u597d\uff0c\u53cd\u5c04\uff01”);<\/div>\n}<\/div>\n}<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\u8f93\u51fa<\/strong>\uff1a<\/p>\n\n\ntext<\/div>\n\n\n<\/div>\n<\/div>\n<\/div>\n<\/code><\/p>\n\n\n\u6d88\u606f\uff1a\u4f60\u597d\uff0c\u53cd\u5c04\uff01<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\u6b64\u793a\u4f8b\u5c55\u793a\u5982\u4f55\u901a\u8fc7\u53cd\u5c04\u52a8\u6001\u8c03\u7528printMessage\u65b9\u6cd5\u3002<\/p>\n
Java\u4e2d\u7684\u52a8\u6001\u4ee3\u7406<\/h2>\n
\u52a8\u6001\u4ee3\u7406\u63d0\u4f9b\u4e86\u4e00\u79cd\u5728\u8fd0\u884c\u65f6\u521b\u5efa\u4ee3\u7406\u5bf9\u8c61\u4ee5\u62e6\u622a\u65b9\u6cd5\u8c03\u7528\u5e76\u589e\u5f3a\u529f\u80fd\u7684\u673a\u5236\uff0c\u4f8b\u5982\u65e5\u5fd7\u8bb0\u5f55\u6216\u4e8b\u52a1\u7ba1\u7406\u3002<\/p>\n
\u9759\u6001\u4ee3\u7406\u4e0e\u52a8\u6001\u4ee3\u7406<\/h3>\n\n- \u9759\u6001\u4ee3\u7406<\/strong>\uff1a\u5728\u7f16\u8bd1\u65f6\u521b\u5efa\u4ee3\u7406\u7c7b\uff0c\u53ef\u80fd\u5bfc\u81f4\u4ee3\u7801\u91cd\u590d\u548c\u7ef4\u62a4\u56f0\u96be\u3002<\/li>\n
- \u52a8\u6001\u4ee3\u7406<\/strong>\uff1a\u5728\u8fd0\u884c\u65f6\u751f\u6210\u4ee3\u7406\u7c7b\uff0c\u63d0\u4f9b\u66f4\u5927\u7684\u7075\u6d3b\u6027\u5e76\u51cf\u5c11\u4ee3\u7801\u5197\u4f59\u3002<\/li>\n<\/ul>\n
JDK\u52a8\u6001\u4ee3\u7406<\/h3>\n
JDK\u52a8\u6001\u4ee3\u7406\u4f9d\u8d56\u4e8ejava.lang.reflect.Proxy\u7c7b\u548cInvocationHandler\u63a5\u53e3\uff0c\u901a\u8fc7\u52a8\u6001\u5b9e\u73b0\u63a5\u53e3\u6765\u5de5\u4f5c\u3002<\/p>\n
\u5173\u952e\u7ec4\u4ef6<\/h4>\n\n- InvocationHandler<\/strong>\uff1a\u5b9a\u4e49invoke\u65b9\u6cd5\u4ee5\u5904\u7406\u4ee3\u7406\u5bf9\u8c61\u4e0a\u7684\u65b9\u6cd5\u8c03\u7528\u3002<\/li>\n
- Proxy<\/strong>\uff1a\u63d0\u4f9bnewProxyInstance\u65b9\u6cd5\u4ee5\u521b\u5efa\u4ee3\u7406\u5bf9\u8c61\u3002<\/li>\n<\/ul>\n
\u521b\u5efaJDK\u52a8\u6001\u4ee3\u7406\u7684\u6b65\u9aa4<\/h4>\n\n- \u5b9a\u4e49\u63a5\u53e3\u53ca\u5176\u5b9e\u73b0\uff08\u771f\u5b9e\u4e3b\u9898\uff09\u3002<\/li>\n
- \u521b\u5efaInvocationHandler\u6765\u5904\u7406\u65b9\u6cd5\u8c03\u7528\u3002<\/li>\n
- \u4f7f\u7528Proxy.newProxyInstance\u751f\u6210\u4ee3\u7406\u5bf9\u8c61\u3002<\/li>\n<\/ol>\n
\u793a\u4f8b\uff1aJDK\u52a8\u6001\u4ee3\u7406<\/h4>\n\n\njava<\/div>\n\n\n<\/div>\n<\/div>\n<\/div>\n<\/code><\/p>\n\n\nimport java.lang.reflect.InvocationHandler;<\/div>\nimport java.lang.reflect.Method;<\/div>\nimport java.lang.reflect.Proxy;<\/div>\n<\/div>\ninterface Service {<\/div>\nvoid performTask(String task);<\/div>\n}<\/div>\n<\/div>\nclass RealService implements Service {<\/div>\npublic void performTask(String task) {<\/div>\nSystem.out.println(“\u6267\u884c\u4efb\u52a1\uff1a” + task);<\/div>\n}<\/div>\n}<\/div>\n<\/div>\nclass ServiceHandler implements InvocationHandler {<\/div>\nprivate final Object target;<\/div>\n<\/div>\npublic ServiceHandler(Object target) {<\/div>\nthis.target = target;<\/div>\n}<\/div>\n<\/div>\n@Override<\/div>\npublic Object invoke(Object proxy, Method method, Object[] args) throws Throwable {<\/div>\nSystem.out.println(“\u8c03\u7528” + method.getName() + “\u4e4b\u524d”);<\/div>\nObject result = method.invoke(target, args);<\/div>\nSystem.out.println(“\u8c03\u7528” + method.getName() + “\u4e4b\u540e”);<\/div>\nreturn result;<\/div>\n}<\/div>\n}<\/div>\n<\/div>\npublic class DynamicProxyExample {<\/div>\npublic static void main(String[] args) {<\/div>\nService realService = new RealService();<\/div>\nInvocationHandler handler = new ServiceHandler(realService);<\/div>\nService proxy = (Service) Proxy.newProxyInstance(<\/div>\nrealService.getClass().getClassLoader(),<\/div>\nrealService.getClass().getInterfaces(),<\/div>\nhandler<\/div>\n);<\/div>\nproxy.performTask(“\u5904\u7406\u6570\u636e”);<\/div>\n}<\/div>\n}<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\u8f93\u51fa<\/strong>\uff1a<\/p>\n\n\ntext<\/div>\n\n\n<\/div>\n<\/div>\n<\/div>\n<\/code><\/p>\n\n\n\u8c03\u7528performTask\u4e4b\u524d<\/div>\n\u6267\u884c\u4efb\u52a1\uff1a\u5904\u7406\u6570\u636e<\/div>\n\u8c03\u7528performTask\u4e4b\u540e<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\u6b64\u793a\u4f8b\u5c55\u793a\u4ee3\u7406\u5982\u4f55\u62e6\u622a\u65b9\u6cd5\u8c03\u7528\u5e76\u6dfb\u52a0\u524d\u540e\u5904\u7406\u903b\u8f91\u3002<\/p>\n
CGLIB\u52a8\u6001\u4ee3\u7406<\/h3>\n
CGLIB\uff08Code Generation Library\uff09\u662f\u4e00\u79cd\u66ff\u4ee3JDK\u52a8\u6001\u4ee3\u7406\u7684\u65b9\u6848\uff0c\u901a\u8fc7\u5b57\u8282\u7801\u64cd\u4f5c\u751f\u6210\u76ee\u6807\u7c7b\u7684\u5b50\u7c7b\u3002<\/p>\n
\u5173\u952e\u7279\u6027<\/h4>\n\n- \u65e0\u9700\u63a5\u53e3<\/strong>\uff1a\u4e0eJDK\u4ee3\u7406\u4e0d\u540c\uff0cCGLIB\u53ef\u4ee5\u4ee3\u7406\u65e0\u9700\u5b9e\u73b0\u63a5\u53e3\u7684\u7c7b\u3002<\/li>\n
- \u6027\u80fd<\/strong>\uff1a\u7531\u4e8e\u4f7f\u7528\u5b57\u8282\u7801\u751f\u6210\uff0cCGLIB\u901a\u5e38\u6bd4JDK\u4ee3\u7406\u66f4\u5feb\u3002<\/li>\n
- \u9650\u5236<\/strong>\uff1a\u65e0\u6cd5\u4ee3\u7406final\u7c7b\u6216\u65b9\u6cd5\u3002<\/li>\n<\/ul>\n
CGLIB\u4e0eJDK\u52a8\u6001\u4ee3\u7406\u5bf9\u6bd4<\/h4>\n\n\n<\/div>\n<\/div>\n\n\n\n\u7279\u6027<\/th>\n JDK\u52a8\u6001\u4ee3\u7406<\/th>\n CGLIB\u52a8\u6001\u4ee3\u7406<\/th>\n<\/tr>\n<\/thead>\n \n\n\u673a\u5236<\/strong><\/td>\n\u57fa\u4e8e\u63a5\u53e3<\/td>\n \u57fa\u4e8e\u5b50\u7c7b<\/td>\n<\/tr>\n \n\u6027\u80fd<\/strong><\/td>\n\u56e0\u53cd\u5c04\u8f83\u6162<\/td>\n \u56e0\u5b57\u8282\u7801\u751f\u6210\u8f83\u5feb<\/td>\n<\/tr>\n \n\u63a5\u53e3\u8981\u6c42<\/strong><\/td>\n\u5fc5\u987b\u5b9e\u73b0\u63a5\u53e3<\/td>\n \u53ef\u9009<\/td>\n<\/tr>\n \nFinal\u7c7b\/\u65b9\u6cd5<\/strong><\/td>\n