{"id":50737,"date":"2023-12-23T10:31:40","date_gmt":"2023-12-23T02:31:40","guid":{"rendered":"https:\/\/www.silicloud.com\/zh\/blog\/java%e5%8f%8d%e5%b0%84%e7%a4%ba%e4%be%8b%e6%95%99%e7%a8%8b\/"},"modified":"2023-12-23T15:28:37","modified_gmt":"2023-12-23T07:28:37","slug":"java%e5%8f%8d%e5%b0%84%e7%a4%ba%e4%be%8b%e6%95%99%e7%a8%8b","status":"publish","type":"post","link":"https:\/\/www.silicloud.com\/zh\/blog\/java%e5%8f%8d%e5%b0%84%e7%a4%ba%e4%be%8b%e6%95%99%e7%a8%8b\/","title":{"rendered":"Java\u53cd\u5c04\u793a\u4f8b\u6559\u7a0b"},"content":{"rendered":"

Java\u53cd\u5c04\u63d0\u4f9b\u4e86\u68c0\u67e5\u548c\u4fee\u6539\u5e94\u7528\u7a0b\u5e8f\u8fd0\u884c\u884c\u4e3a\u7684\u80fd\u529b\u3002Java\u4e2d\u7684\u53cd\u5c04\u662f\u6838\u5fc3Java\u4e2d\u7684\u4e00\u4e2a\u9ad8\u7ea7\u4e3b\u9898\u3002\u4f7f\u7528Java\u53cd\u5c04\uff0c\u6211\u4eec\u53ef\u4ee5\u5728\u8fd0\u884c\u65f6\u68c0\u67e5\u7c7b\u3001\u63a5\u53e3\u3001\u679a\u4e3e\uff0c\u83b7\u53d6\u5b83\u4eec\u7684\u7ed3\u6784\u3001\u65b9\u6cd5\u548c\u5b57\u6bb5\u4fe1\u606f\uff0c\u5373\u4f7f\u5728\u7f16\u8bd1\u65f6\u7c7b\u4e0d\u53ef\u8bbf\u95ee\u3002\u6211\u4eec\u8fd8\u53ef\u4ee5\u4f7f\u7528\u53cd\u5c04\u6765\u5b9e\u4f8b\u5316\u5bf9\u8c61\uff0c\u8c03\u7528\u5176\u65b9\u6cd5\uff0c\u66f4\u6539\u5b57\u6bb5\u503c\u3002<\/p>\n

Java \u53cd\u5c04<\/h2>\n<\/p>\n
    \u5728Java\u4e2d\u7684\u53cd\u5c04
    \nJava\u7c7b\u7684\u53cd\u5c04<\/p>\n

    \u83b7\u53d6\u7c7b\u5bf9\u8c61
    \n\u83b7\u53d6\u7236\u7c7b
    \n\u83b7\u53d6\u516c\u5171\u6210\u5458\u7c7b
    \n\u83b7\u53d6\u58f0\u660e\u7684\u7c7b
    \n\u83b7\u53d6\u58f0\u660e\u7c7b
    \n\u83b7\u53d6\u5305\u540d
    \n\u83b7\u53d6\u7c7b\u4fee\u9970\u7b26
    \n\u83b7\u53d6\u7c7b\u578b\u53c2\u6570
    \n\u83b7\u53d6\u5b9e\u73b0\u7684\u63a5\u53e3
    \n\u83b7\u53d6\u6240\u6709\u516c\u5171\u65b9\u6cd5
    \n\u83b7\u53d6\u6240\u6709\u516c\u5171\u6784\u9020\u51fd\u6570
    \n\u83b7\u53d6\u6240\u6709\u516c\u5171\u5b57\u6bb5
    \n\u83b7\u53d6\u6240\u6709\u6ce8\u91ca<\/p>\n

    Java\u5b57\u6bb5\u7684\u53cd\u5c04<\/p>\n

    \u83b7\u53d6\u516c\u5171\u5b57\u6bb5
    \n\u5b57\u6bb5\u58f0\u660e\u7c7b
    \n\u83b7\u53d6\u5b57\u6bb5\u7c7b\u578b
    \n\u83b7\u53d6\/\u8bbe\u7f6e\u516c\u5171\u5b57\u6bb5\u503c
    \n\u83b7\u53d6\/\u8bbe\u7f6e\u79c1\u6709\u5b57\u6bb5\u503c<\/p>\n

    Java\u65b9\u6cd5\u7684\u53cd\u5c04<\/p>\n

    \u83b7\u53d6\u516c\u5171\u65b9\u6cd5
    \n\u8c03\u7528\u516c\u5171\u65b9\u6cd5
    \n\u8c03\u7528\u79c1\u6709\u65b9\u6cd5<\/p>\n

    Java\u6784\u9020\u51fd\u6570\u7684\u53cd\u5c04<\/p>\n

    \u83b7\u53d6\u516c\u5171\u6784\u9020\u51fd\u6570
    \n\u4f7f\u7528\u6784\u9020\u51fd\u6570\u5b9e\u4f8b\u5316\u5bf9\u8c61<\/p>\n

    Java\u6ce8\u91ca\u7684\u53cd\u5c04<\/ol>\n<\/p>\n

      Java\u4e2d\u7684\u53cd\u5c04<\/ol>\n

      Java\u4e2d\u7684\u53cd\u5c04\u662f\u4e00\u4e2a\u975e\u5e38\u5f3a\u5927\u7684\u6982\u5ff5\uff0c\u5728\u6b63\u5e38\u7684\u7f16\u7a0b\u4e2d\u7528\u5904\u4e0d\u5927\uff0c\u4f46\u5b83\u662f\u5927\u591a\u6570Java\u3001J2EE\u6846\u67b6\u7684\u57fa\u7840\u3002\u4e00\u4e9b\u4f7f\u7528Java\u53cd\u5c04\u7684\u6846\u67b6\u5305\u62ec\uff1a<\/p>\n

        JUnit – \u4f7f\u7528\u53cd\u5c04\u6765\u89e3\u6790@Test\u6ce8\u89e3\u4ee5\u83b7\u53d6\u6d4b\u8bd5\u65b9\u6cd5\u5e76\u8fdb\u884c\u8c03\u7528\u3002
        \nSpring – \u4f9d\u8d56\u6ce8\u5165\uff0c\u8bf7\u9605\u8bfb\u66f4\u591a\u5173\u4e8eSpring\u4f9d\u8d56\u6ce8\u5165\u7684\u5185\u5bb9\u3002
        \nTomcat Web\u5bb9\u5668\u901a\u8fc7\u89e3\u6790web.xml\u6587\u4ef6\u548c\u8bf7\u6c42URI\u5c06\u8bf7\u6c42\u8f6c\u53d1\u5230\u6b63\u786e\u7684\u6a21\u5757\u3002
        \nEclipse\u81ea\u52a8\u5b8c\u6210\u65b9\u6cd5\u540d\u79f0\u3002
        \nStruts
        \nHibernate<\/ol>\n

        \u5217\u8868\u662f\u65e0\u6b62\u5883\u7684\uff0c\u8fd9\u4e9b\u6846\u67b6\u90fd\u4f7f\u7528 Java \u53cd\u5c04\uff0c\u56e0\u4e3a\u5b83\u4eec\u90fd\u65e0\u6cd5\u83b7\u53d6\u548c\u4e86\u89e3\u7528\u6237\u5b9a\u4e49\u7684\u7c7b\u3001\u63a5\u53e3\u53ca\u5176\u65b9\u6cd5\u7b49\u3002\u5728\u6211\u4eec\u5df2\u7ecf\u53ef\u4ee5\u8bbf\u95ee\u8fd9\u4e9b\u7c7b\u548c\u63a5\u53e3\u7684\u60c5\u51b5\u4e0b\uff0c\u6211\u4eec\u4e0d\u5e94\u8be5\u5728\u6b63\u5e38\u7f16\u7a0b\u4e2d\u4f7f\u7528\u53cd\u5c04\uff0c\u56e0\u4e3a\u5b58\u5728\u4ee5\u4e0b\u7f3a\u70b9\u3002<\/p>\n

          \n
        • Poor Performance – Since java reflection resolve the types dynamically, it involves processing like scanning the classpath to find the class to load, causing slow performance.<\/li>\n
        • Security Restrictions – Reflection requires runtime permissions that might not be available for system running under security manager. This can cause you application to fail at runtime because of security manager.<\/li>\n
        • Security Issues – Using reflection we can access part of code that we are not supposed to access, for example we can access private fields of a class and change it\u2019s value. This can be a serious security threat and cause your application to behave abnormally.<\/li>\n
        • High Maintenance – Reflection code is hard to understand and debug, also any issues with the code can\u2019t be found at compile time because the classes might not be available, making it less flexible and hard to maintain.<\/li>\n<\/ul>\n
            Java\u53cd\u5c04\u7c7b\u7684\u7528\u9014<\/ol>\n

            \u5728Java\u4e2d\uff0c\u6bcf\u4e2a\u5bf9\u8c61\u90fd\u662f\u539f\u59cb\u7c7b\u578b\u6216\u5f15\u7528\u7c7b\u578b\u3002\u6240\u6709\u7684\u7c7b\u3001\u679a\u4e3e\u548c\u6570\u7ec4\u90fd\u662f\u5f15\u7528\u7c7b\u578b\uff0c\u5e76\u7ee7\u627f\u81eajava.lang.Object\u3002\u539f\u59cb\u7c7b\u578b\u5305\u62ec\u5e03\u5c14\u578b\u3001\u5b57\u8282\u578b\u3001\u77ed\u6574\u578b\u3001\u6574\u578b\u3001\u957f\u6574\u578b\u3001\u5b57\u7b26\u578b\u3001\u6d6e\u70b9\u578b\u548c\u53cc\u7cbe\u5ea6\u578b\u3002java.lang.Class\u662f\u6240\u6709\u53cd\u5c04\u64cd\u4f5c\u7684\u5165\u53e3\u70b9\u3002\u5bf9\u4e8e\u6bcf\u79cd\u5bf9\u8c61\u7c7b\u578b\uff0cJVM\u4f1a\u5b9e\u4f8b\u5316\u4e00\u4e2a\u4e0d\u53ef\u53d8\u7684java.lang.Class\u5b9e\u4f8b\uff0c\u4ee5\u63d0\u4f9b\u65b9\u6cd5\u6765\u68c0\u67e5\u5bf9\u8c61\u7684\u8fd0\u884c\u65f6\u5c5e\u6027\uff0c\u521b\u5efa\u65b0\u5bf9\u8c61\uff0c\u8c03\u7528\u5176\u65b9\u6cd5\uff0c\u4ee5\u53ca\u83b7\u53d6\/\u8bbe\u7f6e\u5bf9\u8c61\u5b57\u6bb5\u3002\u5728\u672c\u8282\u4e2d\uff0c\u6211\u4eec\u5c06\u8ba8\u8bbaClass\u7684\u4e00\u4e9b\u91cd\u8981\u65b9\u6cd5\uff0c\u4e3a\u4e86\u65b9\u4fbf\u8d77\u89c1\uff0c\u6211\u5c06\u521b\u5efa\u4e00\u4e9b\u5177\u6709\u7ee7\u627f\u5c42\u6b21\u7ed3\u6784\u7684\u7c7b\u548c\u63a5\u53e3\u3002<\/p>\n

            package com.Olivia.reflection;\r\n\r\npublic interface BaseInterface {\r\n\t\r\n\tpublic int interfaceInt=0;\r\n\t\r\n\tvoid method1();\r\n\t\r\n\tint method2(String str);\r\n}\r\n<\/code><\/pre>\n
            package com.Olivia.reflection;\r\n\r\npublic class BaseClass {\r\n\r\n\tpublic int baseInt;\r\n\t\r\n\tprivate static void method3(){\r\n\t\tSystem.out.println(\"Method3\");\r\n\t}\r\n\t\r\n\tpublic int method4(){\r\n\t\tSystem.out.println(\"Method4\");\r\n\t\treturn 0;\r\n\t}\r\n\t\r\n\tpublic static int method5(){\r\n\t\tSystem.out.println(\"Method5\");\r\n\t\treturn 0;\r\n\t}\r\n\t\r\n\tvoid method6(){\r\n\t\tSystem.out.println(\"Method6\");\r\n\t}\r\n\t\r\n\t\/\/ inner public class\r\n\tpublic class BaseClassInnerClass{}\r\n\t\t\r\n\t\/\/member public enum\r\n\tpublic enum BaseClassMemberEnum{}\r\n}\r\n<\/code><\/pre>\n
            package com.Olivia.reflection;\r\n\r\n@Deprecated\r\npublic class ConcreteClass extends BaseClass implements BaseInterface {\r\n\r\n\tpublic int publicInt;\r\n\tprivate String privateString=\"private string\";\r\n\tprotected boolean protectedBoolean;\r\n\tObject defaultObject;\r\n\t\r\n\tpublic ConcreteClass(int i){\r\n\t\tthis.publicInt=i;\r\n\t}\r\n\r\n\t@Override\r\n\tpublic void method1() {\r\n\t\tSystem.out.println(\"Method1 impl.\");\r\n\t}\r\n\r\n\t@Override\r\n\tpublic int method2(String str) {\r\n\t\tSystem.out.println(\"Method2 impl.\");\r\n\t\treturn 0;\r\n\t}\r\n\t\r\n\t@Override\r\n\tpublic int method4(){\r\n\t\tSystem.out.println(\"Method4 overriden.\");\r\n\t\treturn 0;\r\n\t}\r\n\t\r\n\tpublic int method5(int i){\r\n\t\tSystem.out.println(\"Method4 overriden.\");\r\n\t\treturn 0;\r\n\t}\r\n\t\r\n\t\/\/ inner classes\r\n\tpublic class ConcreteClassPublicClass{}\r\n\tprivate class ConcreteClassPrivateClass{}\r\n\tprotected class ConcreteClassProtectedClass{}\r\n\tclass ConcreteClassDefaultClass{}\r\n\t\r\n\t\/\/member enum\r\n\tenum ConcreteClassDefaultEnum{}\r\n\tpublic enum ConcreteClassPublicEnum{}\r\n\t\r\n\t\/\/member interface\r\n\tpublic interface ConcreteClassPublicInterface{}\r\n\r\n}\r\n<\/code><\/pre>\n
            \u8ba9\u6211\u4eec\u6765\u770b\u4e00\u4e9b\u7c7b\u7684\u91cd\u8981\u53cd\u5c04\u65b9\u6cd5\u3002<\/p>\n
            \u83b7\u53d6\u7c7b\u5bf9\u8c61<\/h3>\n
            \u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u4e09\u79cd\u65b9\u6cd5\u6765\u83b7\u53d6\u4e00\u4e2a\u5bf9\u8c61\u7684\u7c7b – \u901a\u8fc7\u9759\u6001\u53d8\u91cf\u7c7b\u3001\u4f7f\u7528\u5bf9\u8c61\u7684getClass()\u65b9\u6cd5\u4ee5\u53cajava.lang.Class.forName(String fullyClassifiedClassName)\u3002\u5bf9\u4e8e\u539f\u59cb\u7c7b\u578b\u548c\u6570\u7ec4\uff0c\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u9759\u6001\u53d8\u91cf\u7c7b\u3002\u5c01\u88c5\u7c7b\u63d0\u4f9b\u4e86\u53e6\u4e00\u4e2a\u9759\u6001\u53d8\u91cfTYPE\u6765\u83b7\u53d6\u7c7b\u3002<\/p>\n
            \/\/ Get Class using reflection\r\nClass<?> concreteClass = ConcreteClass.class;\r\nconcreteClass = new ConcreteClass(5).getClass();\r\ntry {\r\n\t\/\/ below method is used most of the times in frameworks like JUnit\r\n\t\/\/Spring dependency injection, Tomcat web container\r\n\t\/\/Eclipse auto completion of method names, hibernate, Struts2 etc.\r\n\t\/\/because ConcreteClass is not available at compile time\r\n\tconcreteClass = Class.forName(\"com.Olivia.reflection.ConcreteClass\");\r\n} catch (ClassNotFoundException e) {\r\n\te.printStackTrace();\r\n}\r\nSystem.out.println(concreteClass.getCanonicalName()); \/\/ prints com.Olivia.reflection.ConcreteClass\r\n\r\n\/\/for primitive types, wrapper classes and arrays\r\nClass<?> booleanClass = boolean.class;\r\nSystem.out.println(booleanClass.getCanonicalName()); \/\/ prints boolean\r\n\r\nClass<?> cDouble = Double.TYPE;\r\nSystem.out.println(cDouble.getCanonicalName()); \/\/ prints double\r\n\r\nClass<?> cDoubleArray = Class.forName(\"[D\");\r\nSystem.out.println(cDoubleArray.getCanonicalName()); \/\/prints double[]\r\n\r\nClass<?> twoDStringArray = String[][].class;\r\nSystem.out.println(twoDStringArray.getCanonicalName()); \/\/ prints java.lang.String[][]\r\n<\/code><\/pre>\n
            getCanonicalName()\u65b9\u6cd5\u8fd4\u56de\u5e95\u5c42\u7c7b\u7684\u89c4\u8303\u540d\u79f0\u3002\u8bf7\u6ce8\u610f\uff0cjava.lang.Class\u4f7f\u7528\u6cdb\u578b\uff0c\u5b83\u6709\u52a9\u4e8e\u6846\u67b6\u786e\u4fdd\u68c0\u7d22\u5230\u7684\u7c7b\u662f\u6846\u67b6\u57fa\u7c7b\u7684\u5b50\u7c7b\u3002\u67e5\u770bJava\u6cdb\u578b\u6559\u7a0b\u4ee5\u4e86\u89e3\u6cdb\u578b\u53ca\u5176\u901a\u914d\u7b26\u7528\u6cd5\u3002<\/p>\n
            \u53d6\u5f97\u8d85\u7c7b<\/h3>\n
            \u5728Class\u5bf9\u8c61\u4e0a\u8c03\u7528getSuperclass()\u65b9\u6cd5\u4f1a\u8fd4\u56de\u8be5\u7c7b\u7684\u7236\u7c7b\u3002\u5982\u679c\u8fd9\u4e2aClass\u4ee3\u8868\u7684\u662fObject\u7c7b\u3001\u4e00\u4e2a\u63a5\u53e3\u3001\u539f\u59cb\u7c7b\u578b\u6216\u8005void\uff0c\u5219\u8fd4\u56denull\u3002\u5982\u679c\u8fd9\u4e2a\u5bf9\u8c61\u4ee3\u8868\u7684\u662f\u4e00\u4e2a\u6570\u7ec4\u7c7b\uff0c\u5219\u8fd4\u56de\u4ee3\u8868Object\u7c7b\u7684Class\u5bf9\u8c61\u3002<\/p>\n
            Class<?> superClass = Class.forName(\"com.Olivia.reflection.ConcreteClass\").getSuperclass();\r\nSystem.out.println(superClass); \/\/ prints \"class com.Olivia.reflection.BaseClass\"\r\nSystem.out.println(Object.class.getSuperclass()); \/\/ prints \"null\"\r\nSystem.out.println(String[][].class.getSuperclass());\/\/ prints \"class java.lang.Object\"\r\n<\/code><\/pre>\n
            \u83b7\u53d6\u516c\u5171\u6210\u5458\u7c7b<\/h3>\n
            \u83b7\u53d6\u5bf9\u8c61\u7684\u7c7b\u7684getClasses()\u65b9\u6cd5\u8fd4\u56de\u4e00\u4e2a\u6570\u7ec4\uff0c\u8be5\u6570\u7ec4\u5305\u542b\u8868\u793a\u8be5\u7c7b\u7684\u6240\u6709\u516c\u5171\u7c7b\u3001\u63a5\u53e3\u548c\u679a\u4e3e\u7c7b\u578b\u6210\u5458\u7684Class\u5bf9\u8c61\u3002\u5176\u4e2d\u5305\u62ec\u4ece\u7236\u7c7b\u7ee7\u627f\u7684\u516c\u5171\u7c7b\u548c\u63a5\u53e3\u6210\u5458\uff0c\u4ee5\u53ca\u7531\u8be5\u7c7b\u58f0\u660e\u7684\u516c\u5171\u7c7b\u548c\u63a5\u53e3\u6210\u5458\u3002\u5982\u679c\u8be5Class\u5bf9\u8c61\u6ca1\u6709\u516c\u5171\u6210\u5458\u7c7b\u6216\u63a5\u53e3\uff0c\u6216\u8005\u8be5Class\u5bf9\u8c61\u8868\u793a\u539f\u59cb\u7c7b\u578b\u3001\u6570\u7ec4\u7c7b\u6216void\uff0c\u5219\u8be5\u65b9\u6cd5\u8fd4\u56de\u957f\u5ea6\u4e3a0\u7684\u6570\u7ec4\u3002<\/p>\n
            Class<?>[] classes = concreteClass.getClasses();\r\n\/\/[class com.Olivia.reflection.ConcreteClass$ConcreteClassPublicClass, \r\n\/\/class com.Olivia.reflection.ConcreteClass$ConcreteClassPublicEnum, \r\n\/\/interface com.Olivia.reflection.ConcreteClass$ConcreteClassPublicInterface,\r\n\/\/class com.Olivia.reflection.BaseClass$BaseClassInnerClass, \r\n\/\/class com.Olivia.reflection.BaseClass$BaseClassMemberEnum]\r\nSystem.out.println(Arrays.toString(classes));\r\n<\/code><\/pre>\n
            \u83b7\u53d6\u58f0\u660e\u7684\u7c7b<\/h3>\n
            getDeclaredClasses\uff08\uff09\u65b9\u6cd5\u8fd4\u56de\u4e00\u4e2a\u6570\u7ec4\uff0c\u5176\u4e2d\u5305\u542b\u53cd\u6620\u7531\u6b64Class\u5bf9\u8c61\u8868\u793a\u7684\u7c7b\u7684\u6240\u6709\u6210\u5458\u58f0\u660e\u7684\u7c7b\u548c\u63a5\u53e3\u7684Class\u5bf9\u8c61\u3002\u8fd4\u56de\u7684\u6570\u7ec4\u4e0d\u5305\u62ec\u5728\u7ee7\u627f\u7684\u7c7b\u548c\u63a5\u53e3\u4e2d\u58f0\u660e\u7684\u7c7b\u3002<\/p>\n
            \/\/getting all of the classes, interfaces, and enums that are explicitly declared in ConcreteClass\r\nClass<?>[] explicitClasses = Class.forName(\"com.Olivia.reflection.ConcreteClass\").getDeclaredClasses();\r\n\/\/prints [class com.Olivia.reflection.ConcreteClass$ConcreteClassDefaultClass, \r\n\/\/class com.Olivia.reflection.ConcreteClass$ConcreteClassDefaultEnum, \r\n\/\/class com.Olivia.reflection.ConcreteClass$ConcreteClassPrivateClass, \r\n\/\/class com.Olivia.reflection.ConcreteClass$ConcreteClassProtectedClass, \r\n\/\/class com.Olivia.reflection.ConcreteClass$ConcreteClassPublicClass, \r\n\/\/class com.Olivia.reflection.ConcreteClass$ConcreteClassPublicEnum, \r\n\/\/interface com.Olivia.reflection.ConcreteClass$ConcreteClassPublicInterface]\r\nSystem.out.println(Arrays.toString(explicitClasses));\r\n<\/code><\/pre>\n
            \u83b7\u53d6\u58f0\u660e\u7c7b<\/h3>\n
            getDeclaringClass()\u65b9\u6cd5\u8fd4\u56deClass\u5bf9\u8c61\uff0c\u8be5\u5bf9\u8c61\u4ee3\u8868\u4e86\u58f0\u660e\u8be5\u65b9\u6cd5\u7684\u7c7b\u3002<\/p>\n
            Class<?> innerClass = Class.forName(\"com.Olivia.reflection.ConcreteClass$ConcreteClassDefaultClass\");\r\n\/\/prints com.Olivia.reflection.ConcreteClass\r\nSystem.out.println(innerClass.getDeclaringClass().getCanonicalName());\r\nSystem.out.println(innerClass.getEnclosingClass().getCanonicalName());\r\n<\/code><\/pre>\n
            \u83b7\u53d6\u8f6f\u4ef6\u5305\u540d\u79f0<\/h3>\n
            getPackage() \u65b9\u6cd5\u8fd4\u56de\u8be5\u7c7b\u7684\u5305\u3002\u8be5\u7c7b\u7684\u7c7b\u52a0\u8f7d\u5668\u7528\u4e8e\u67e5\u627e\u5305\u3002\u6211\u4eec\u53ef\u4ee5\u8c03\u7528 Package \u7684 getName() \u65b9\u6cd5\u6765\u83b7\u53d6\u5305\u7684\u540d\u79f0\u3002<\/p>\n
            \/\/prints \"com.Olivia.reflection\"\r\nSystem.out.println(Class.forName(\"com.Olivia.reflection.BaseInterface\").getPackage().getName());\r\n<\/code><\/pre>\n
            \u83b7\u53d6\u7c7b\u7684\u4fee\u9970\u7b26<\/h3>\n
            getModifiers()\u65b9\u6cd5\u8fd4\u56de\u7c7b\u4fee\u9970\u7b26\u7684\u6574\u6570\u8868\u793a\u5f62\u5f0f\uff0c\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528java.lang.reflect.Modifier.toString()\u65b9\u6cd5\u4ee5\u5b57\u7b26\u4e32\u683c\u5f0f\u83b7\u53d6\u6e90\u4ee3\u7801\u4e2d\u4f7f\u7528\u7684\u4fee\u9970\u7b26\u3002<\/p>\n
            System.out.println(Modifier.toString(concreteClass.getModifiers())); \/\/prints \"public\"\r\n\/\/prints \"public abstract interface\"\r\nSystem.out.println(Modifier.toString(Class.forName(\"com.Olivia.reflection.BaseInterface\").getModifiers())); \r\n<\/code><\/pre>\n
            \u83b7\u53d6\u7c7b\u578b\u53c2\u6570<\/h3>\n
            \u5982\u679c\u7c7b\u4e0e\u4efb\u4f55\u7c7b\u578b\u53c2\u6570\u76f8\u5173\u8054\uff0c\u5219getTypeParameters()\u4f1a\u8fd4\u56deTypeVariable\u6570\u7ec4\u3002\u8fd9\u4e9b\u7c7b\u578b\u53c2\u6570\u4ee5\u58f0\u660e\u7684\u76f8\u540c\u987a\u5e8f\u8fd4\u56de\u3002<\/p>\n
            \/\/Get Type parameters (generics)\r\nTypeVariable<?>[] typeParameters = Class.forName(\"java.util.HashMap\").getTypeParameters();\r\nfor(TypeVariable<?> t : typeParameters)\r\nSystem.out.print(t.getName()+\",\");\r\n<\/code><\/pre>\n
            \u83b7\u53d6\u5df2\u5b9e\u73b0\u7684\u63a5\u53e3<\/h3>\n
            getGenericInterfaces() \u65b9\u6cd5\u8fd4\u56de\u4f7f\u7528\u6cdb\u578b\u7c7b\u578b\u4fe1\u606f\u5b9e\u73b0\u7684\u63a5\u53e3\u6570\u7ec4\u3002\u6211\u4eec\u8fd8\u53ef\u4ee5\u4f7f\u7528 getInterfaces() \u83b7\u53d6\u6240\u6709\u5b9e\u73b0\u7684\u63a5\u53e3\u7684\u7c7b\u8868\u793a\u3002<\/p>\n
            Type[] interfaces = Class.forName(\"java.util.HashMap\").getGenericInterfaces();\r\n\/\/prints \"[java.util.Map<K, V>, interface java.lang.Cloneable, interface java.io.Serializable]\"\r\nSystem.out.println(Arrays.toString(interfaces));\r\n\/\/prints \"[interface java.util.Map, interface java.lang.Cloneable, interface java.io.Serializable]\"\r\nSystem.out.println(Arrays.toString(Class.forName(\"java.util.HashMap\").getInterfaces()));\t\t\r\n<\/code><\/pre>\n
            \u83b7\u53d6\u6240\u6709\u516c\u5171\u65b9\u6cd5<\/h3>\n
            getMethods()\u65b9\u6cd5\u8fd4\u56de\u5305\u62ec\u5176\u7236\u7c7b\u548c\u7236\u63a5\u53e3\u7684\u516c\u5171\u65b9\u6cd5\u5728\u5185\u7684Class\u7684\u516c\u5171\u65b9\u6cd5\u6570\u7ec4\u3002<\/p>\n
            Method[] publicMethods = Class.forName(\"com.Olivia.reflection.ConcreteClass\").getMethods();\r\n\/\/prints public methods of ConcreteClass, BaseClass, Object\r\nSystem.out.println(Arrays.toString(publicMethods));\r\n<\/code><\/pre>\n
            \u83b7\u53d6\u6240\u6709\u516c\u5171\u6784\u9020\u51fd\u6570<\/h3>\n
            getConstructors\uff08\uff09\u65b9\u6cd5\u8fd4\u56de\u5bf9\u8c61\u7c7b\u53c2\u8003\u7684\u516c\u5171\u6784\u9020\u51fd\u6570\u5217\u8868\u3002<\/p>\n
            \/\/Get All public constructors\r\nConstructor<?>[] publicConstructors = Class.forName(\"com.Olivia.reflection.ConcreteClass\").getConstructors();\r\n\/\/prints public constructors of ConcreteClass\r\nSystem.out.println(Arrays.toString(publicConstructors));\r\n<\/code><\/pre>\n
            \u83b7\u53d6\u6240\u6709\u516c\u5171\u5b57\u6bb5<\/h3>\n
            getFields()\u65b9\u6cd5\u8fd4\u56de\u7c7b\u7684\u516c\u5171\u5b57\u6bb5\u6570\u7ec4\uff0c\u5305\u62ec\u5176\u7236\u7c7b\u548c\u7236\u63a5\u53e3\u7684\u516c\u5171\u5b57\u6bb5\u3002<\/p>\n
            \/\/Get All public fields\r\nField[] publicFields = Class.forName(\"com.Olivia.reflection.ConcreteClass\").getFields();\r\n\/\/prints public fields of ConcreteClass, it's superclass and super interfaces\r\nSystem.out.println(Arrays.toString(publicFields));\r\n<\/code><\/pre>\n
            \u83b7\u53d6\u6240\u6709\u7684\u6ce8\u91ca<\/h3>\n
            getAnnotations()\u65b9\u6cd5\u8fd4\u56de\u5143\u7d20\u7684\u6240\u6709\u6ce8\u89e3\uff0c\u6211\u4eec\u53ef\u4ee5\u7528\u5b83\u4e0e\u7c7b\u3001\u5b57\u6bb5\u548c\u65b9\u6cd5\u4e00\u8d77\u4f7f\u7528\u3002\u6ce8\u610f\uff0c\u53ea\u6709\u4f7f\u7528\u53cd\u5c04\u673a\u5236\u8fdb\u884c\u8fd0\u884c\u65f6\u4fdd\u7559\u7b56\u7565\u7684\u6ce8\u89e3\u624d\u53ef\u7528\uff0c\u8bf7\u67e5\u770bJava\u6ce8\u89e3\u6559\u7a0b\u3002\u6211\u4eec\u5c06\u5728\u540e\u9762\u7684\u7ae0\u8282\u4e2d\u8be6\u7ec6\u8ba8\u8bba\u8fd9\u4e2a\u95ee\u9898\u3002<\/p>\n
            java.lang.annotation.Annotation[] annotations = Class.forName(\"com.Olivia.reflection.ConcreteClass\").getAnnotations();\r\n\/\/prints [@java.lang.Deprecated()]\r\nSystem.out.println(Arrays.toString(annotations));\r\n<\/code><\/pre>\n
              Java\u53cd\u5c04\u7528\u4e8e\u5b57\u6bb5<\/ol>\n
              \u53cd\u5c04API\u63d0\u4f9b\u4e86\u51e0\u79cd\u65b9\u6cd5\u6765\u5206\u6790\u7c7b\u7684\u5b57\u6bb5\uff0c\u5e76\u5728\u8fd0\u884c\u65f6\u4fee\u6539\u5b83\u4eec\u7684\u503c\u3002\u5728\u672c\u8282\u4e2d\uff0c\u6211\u4eec\u5c06\u4ecb\u7ecd\u4e00\u4e9b\u5e38\u7528\u7684\u53cd\u5c04\u65b9\u6cd5\uff0c\u7528\u4e8e\u5904\u7406\u65b9\u6cd5\u3002<\/p>\n
              \u83b7\u53d6\u516c\u5171\u5b57\u6bb5<\/h3>\n
              \u5728\u4e0a\u4e00\u90e8\u5206\u4e2d\uff0c\u6211\u4eec\u770b\u5230\u4e86\u5982\u4f55\u83b7\u53d6\u4e00\u4e2a\u7c7b\u7684\u6240\u6709\u516c\u5171\u5b57\u6bb5\u7684\u5217\u8868\u3002\u53cd\u5c04API\u8fd8\u63d0\u4f9b\u4e86\u901a\u8fc7getField()\u65b9\u6cd5\u83b7\u53d6\u7279\u5b9a\u516c\u5171\u5b57\u6bb5\u7684\u65b9\u6cd5\u3002\u8be5\u65b9\u6cd5\u4f1a\u5728\u6307\u5b9a\u7684\u7c7b\u5f15\u7528\u4e2d\u67e5\u627e\u8be5\u5b57\u6bb5\uff0c\u7136\u540e\u5728\u8d85\u7ea7\u63a5\u53e3\u548c\u8d85\u7ea7\u7c7b\u4e2d\u67e5\u627e\u3002<\/p>\n
              Field field = Class.forName(\"com.Olivia.reflection.ConcreteClass\").getField(\"interfaceInt\");\r\n<\/code><\/pre>\n
              \u5982\u679c\u5728ConcreteClass\u4e2d\u5b9e\u73b0\u4e86BaseInterface\u63a5\u53e3\uff0c\u4ee5\u4e0a\u8c03\u7528\u5c06\u8fd4\u56deBaseInterface\u4e2d\u7684\u5b57\u6bb5\u3002\u5982\u679c\u672a\u627e\u5230\u8be5\u5b57\u6bb5\uff0c\u5219\u4f1a\u629b\u51faNoSuchFieldException\u5f02\u5e38\u3002<\/p>\n
              \u58f0\u660e\u5b57\u6bb5\u7684\u7c7b<\/h3>\n
              \u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u5b57\u6bb5\u5bf9\u8c61\u7684getDeclaringClass()\u65b9\u6cd5\u6765\u83b7\u53d6\u58f0\u660e\u8be5\u5b57\u6bb5\u7684\u7c7b\u3002<\/p>\n
              try {\r\n\tField field = Class.forName(\"com.Olivia.reflection.ConcreteClass\").getField(\"interfaceInt\");\r\n\tClass<?> fieldClass = field.getDeclaringClass();\r\n\tSystem.out.println(fieldClass.getCanonicalName()); \/\/prints com.Olivia.reflection.BaseInterface\r\n} catch (NoSuchFieldException | SecurityException e) {\r\n\te.printStackTrace();\r\n}\r\n<\/code><\/pre>\n
              \u83b7\u53d6\u5b57\u6bb5\u7c7b\u578b<\/h3>\n
              \u5982\u679c\u5b57\u6bb5\u662f\u539f\u59cb\u6570\u636e\u7c7b\u578b\uff0cgetType()\u65b9\u6cd5\u8fd4\u56de\u58f0\u660e\u5b57\u6bb5\u7c7b\u578b\u7684Class\u5bf9\u8c61\uff0c\u5982\u679c\u5b57\u6bb5\u662f\u5305\u88c5\u7c7b\u5bf9\u8c61\uff0c\u5219\u8fd4\u56de\u5305\u88c5\u7c7b\u5bf9\u8c61\u3002<\/p>\n
              Field field = Class.forName(\"com.Olivia.reflection.ConcreteClass\").getField(\"publicInt\");\r\nClass<?> fieldType = field.getType();\r\nSystem.out.println(fieldType.getCanonicalName()); \/\/prints int\t\t\t\r\n<\/code><\/pre>\n
              \u83b7\u53d6\/\u8bbe\u7f6e\u516c\u5171\u5b57\u6bb5\u7684\u503c<\/h3>\n
              \u6211\u4eec\u53ef\u4ee5\u901a\u8fc7\u53cd\u5c04\u6765\u83b7\u53d6\u548c\u8bbe\u7f6e\u5bf9\u8c61\u4e2d\u5b57\u6bb5\u7684\u503c\u3002<\/p>\n
              Field field = Class.forName(\"com.Olivia.reflection.ConcreteClass\").getField(\"publicInt\");\r\nConcreteClass obj = new ConcreteClass(5);\r\nSystem.out.println(field.get(obj)); \/\/prints 5\r\nfield.setInt(obj, 10); \/\/setting field value to 10 in object\r\nSystem.out.println(field.get(obj)); \/\/prints 10\r\n<\/code><\/pre>\n
              get()\u65b9\u6cd5\u8fd4\u56deObject\u7c7b\u578b\u7684\u5bf9\u8c61\uff0c\u6240\u4ee5\u5982\u679c\u5b57\u6bb5\u662f\u539f\u59cb\u7c7b\u578b\uff0c\u5b83\u4f1a\u8fd4\u56de\u5bf9\u5e94\u7684\u5305\u88c5\u7c7b\u3002\u5982\u679c\u5b57\u6bb5\u662f\u9759\u6001\u7684\uff0c\u5728get()\u65b9\u6cd5\u4e2d\u6211\u4eec\u53ef\u4ee5\u4f20\u9012null\u4f5c\u4e3a\u53c2\u6570\u3002\u6709\u51e0\u4e2aset*()\u65b9\u6cd5\u53ef\u4ee5\u5c06\u5bf9\u8c61\u8bbe\u7f6e\u5230\u5b57\u6bb5\u4e2d\uff0c\u6216\u8005\u5c06\u4e0d\u540c\u7c7b\u578b\u7684\u539f\u59cb\u7c7b\u578b\u8bbe\u7f6e\u5230\u5b57\u6bb5\u4e2d\u3002\u6211\u4eec\u53ef\u4ee5\u83b7\u53d6\u5b57\u6bb5\u7684\u7c7b\u578b\uff0c\u7136\u540e\u8c03\u7528\u6b63\u786e\u7684\u51fd\u6570\u6765\u6b63\u786e\u8bbe\u7f6e\u5b57\u6bb5\u7684\u503c\u3002\u5982\u679c\u5b57\u6bb5\u662ffinal\u7684\uff0cset()\u65b9\u6cd5\u4f1a\u629b\u51fajava.lang.IllegalAccessException\u5f02\u5e38\u3002<\/p>\n
              \u8bbe\u7f6e\/\u83b7\u53d6\u79c1\u6709\u5b57\u6bb5\u7684\u503c\u3002<\/h3>\n
              \u6211\u4eec\u77e5\u9053\uff0c\u79c1\u6709\u5b57\u6bb5\u548c\u65b9\u6cd5\u5728\u7c7b\u5916\u90e8\u662f\u65e0\u6cd5\u8bbf\u95ee\u7684\uff0c\u4f46\u662f\u901a\u8fc7\u4f7f\u7528\u53cd\u5c04\uff0c\u6211\u4eec\u53ef\u4ee5\u901a\u8fc7\u5173\u95edJava\u5bf9\u5b57\u6bb5\u4fee\u9970\u7b26\u7684\u8bbf\u95ee\u68c0\u67e5\u6765\u83b7\u53d6\/\u8bbe\u7f6e\u79c1\u6709\u5b57\u6bb5\u7684\u503c\u3002<\/p>\n
              Field privateField = Class.forName(\"com.Olivia.reflection.ConcreteClass\").getDeclaredField(\"privateString\");\r\n\/\/turning off access check with below method call\r\nprivateField.setAccessible(true);\r\nConcreteClass objTest = new ConcreteClass(1);\r\nSystem.out.println(privateField.get(objTest)); \/\/ prints \"private string\"\r\nprivateField.set(objTest, \"private string updated\");\r\nSystem.out.println(privateField.get(objTest)); \/\/prints \"private string updated\"\r\n<\/code><\/pre>\n
                Java\u65b9\u6cd5\u7684\u53cd\u5c04<\/ol>\n
                \u901a\u8fc7\u53cd\u5c04\uff0c\u6211\u4eec\u53ef\u4ee5\u83b7\u53d6\u6709\u5173\u65b9\u6cd5\u7684\u4fe1\u606f\u5e76\u6267\u884c\u5b83\u3002\u5728\u672c\u8282\u4e2d\uff0c\u6211\u4eec\u5c06\u5b66\u4e60\u4e0d\u540c\u7684\u65b9\u6cd5\u6765\u83b7\u53d6\u4e00\u4e2a\u65b9\u6cd5\uff0c\u8c03\u7528\u4e00\u4e2a\u65b9\u6cd5\u5e76\u8bbf\u95ee\u79c1\u6709\u65b9\u6cd5\u3002<\/p>\n
                \u83b7\u53d6\u516c\u5171\u65b9\u6cd5<\/h3>\n
                \u6211\u4eec\u53ef\u4ee5\u4f7f\u7528getMethod()\u65b9\u6cd5\u6765\u83b7\u53d6\u4e00\u4e2a\u7c7b\u7684\u516c\u5171\u65b9\u6cd5\uff0c\u6211\u4eec\u9700\u8981\u4f20\u9012\u65b9\u6cd5\u7684\u540d\u79f0\u548c\u53c2\u6570\u7c7b\u578b\u3002\u5982\u679c\u5728\u7c7b\u4e2d\u627e\u4e0d\u5230\u8be5\u65b9\u6cd5\uff0c\u53cd\u5c04API\u4f1a\u5728\u7236\u7c7b\u4e2d\u67e5\u627e\u8be5\u65b9\u6cd5\u3002\u5728\u4e0b\u9762\u7684\u793a\u4f8b\u4e2d\uff0c\u6211\u4f7f\u7528\u53cd\u5c04\u6765\u83b7\u53d6HashMap\u7684put()\u65b9\u6cd5\u3002\u793a\u4f8b\u8fd8\u5c55\u793a\u4e86\u5982\u4f55\u83b7\u53d6\u65b9\u6cd5\u7684\u53c2\u6570\u7c7b\u578b\u3001\u65b9\u6cd5\u4fee\u9970\u7b26\u548c\u8fd4\u56de\u7c7b\u578b\u3002<\/p>\n
                Method method = Class.forName(\"java.util.HashMap\").getMethod(\"put\", Object.class, Object.class);\r\n\/\/get method parameter types, prints \"[class java.lang.Object, class java.lang.Object]\"\r\nSystem.out.println(Arrays.toString(method.getParameterTypes()));\r\n\/\/get method return type, return \"class java.lang.Object\", class reference for void\r\nSystem.out.println(method.getReturnType());\r\n\/\/get method modifiers\r\nSystem.out.println(Modifier.toString(method.getModifiers())); \/\/prints \"public\"\r\n<\/code><\/pre>\n
                \u8c03\u7528\u516c\u5171\u65b9\u6cd5<\/h3>\n
                \u6211\u4eec\u53ef\u4ee5\u4f7f\u7528Method\u5bf9\u8c61\u7684invoke()\u65b9\u6cd5\u6765\u8c03\u7528\u4e00\u4e2a\u65b9\u6cd5\uff0c\u5728\u4e0b\u9762\u7684\u793a\u4f8b\u4ee3\u7801\u4e2d\uff0c\u6211\u901a\u8fc7\u53cd\u5c04\u8c03\u7528HashMap\u7684put\u65b9\u6cd5\u3002<\/p>\n
                Method method = Class.forName(\"java.util.HashMap\").getMethod(\"put\", Object.class, Object.class);\r\nMap<String, String> hm = new HashMap<>();\r\nmethod.invoke(hm, \"key\", \"value\");\r\nSystem.out.println(hm); \/\/ prints {key=value}\r\n<\/code><\/pre>\n
                \u5982\u679c\u8fd9\u4e2a\u65b9\u6cd5\u662f\u9759\u6001\u7684\uff0c\u6211\u4eec\u53ef\u4ee5\u5c06NULL\u4f20\u9012\u4f5c\u4e3a\u5bf9\u8c61\u53c2\u6570\u3002<\/p>\n
                \u8c03\u7528\u79c1\u6709\u65b9\u6cd5<\/h3>\n
                \u6211\u4eec\u53ef\u4ee5\u4f7f\u7528getDeclaredMethod()\u6765\u83b7\u53d6\u79c1\u6709\u65b9\u6cd5\uff0c\u7136\u540e\u5173\u95ed\u8bbf\u95ee\u68c0\u67e5\u6765\u8c03\u7528\u5b83\uff0c\u4e0b\u9762\u7684\u4f8b\u5b50\u5c55\u793a\u4e86\u6211\u4eec\u5982\u4f55\u8c03\u7528\u6ca1\u6709\u53c2\u6570\u4e14\u4e3a\u9759\u6001\u65b9\u6cd5\u7684BaseClass\u7684method3()\u3002<\/p>\n
                \/\/invoking private method\r\nMethod method = Class.forName(\"com.Olivia.reflection.BaseClass\").getDeclaredMethod(\"method3\", null);\r\nmethod.setAccessible(true);\r\nmethod.invoke(null, null); \/\/prints \"Method3\"\r\n<\/code><\/pre>\n
                  \u6784\u9020\u51fd\u6570\u7684Java\u53cd\u5c04<\/ol>\n
                  \u53cd\u5c04API\u63d0\u4f9b\u4e86\u83b7\u53d6\u7c7b\u7684\u6784\u9020\u51fd\u6570\u8fdb\u884c\u5206\u6790\u7684\u65b9\u6cd5\uff0c\u6211\u4eec\u53ef\u4ee5\u901a\u8fc7\u8c03\u7528\u6784\u9020\u51fd\u6570\u6765\u521b\u5efa\u7c7b\u7684\u65b0\u5b9e\u4f8b\u3002\u6211\u4eec\u5df2\u7ecf\u5b66\u4e60\u4e86\u5982\u4f55\u83b7\u53d6\u6240\u6709\u7684\u516c\u5171\u6784\u9020\u51fd\u6570\u3002<\/p>\n
                  \u83b7\u53d6\u516c\u5171\u6784\u9020\u51fd\u6570\u3002<\/h3>\n
                  \u6211\u4eec\u53ef\u4ee5\u4f7f\u7528\u7c7b\u5bf9\u8c61\u7684getConstructor()\u65b9\u6cd5\u6765\u83b7\u53d6\u7279\u5b9a\u7684\u516c\u5171\u6784\u9020\u51fd\u6570\u3002\u4e0b\u9762\u7684\u793a\u4f8b\u5c55\u793a\u4e86\u5982\u4f55\u83b7\u53d6\u4e0a\u9762\u5b9a\u4e49\u7684ConcreteClass\u7684\u6784\u9020\u51fd\u6570\u4ee5\u53caHashMap\u7684\u65e0\u53c2\u6784\u9020\u51fd\u6570\u3002\u5b83\u8fd8\u5c55\u793a\u4e86\u5982\u4f55\u83b7\u53d6\u6784\u9020\u51fd\u6570\u7684\u53c2\u6570\u7c7b\u578b\u6570\u7ec4\u3002<\/p>\n
                  Constructor<?> constructor = Class.forName(\"com.Olivia.reflection.ConcreteClass\").getConstructor(int.class);\r\n\/\/getting constructor parameters\r\nSystem.out.println(Arrays.toString(constructor.getParameterTypes())); \/\/ prints \"[int]\"\r\n\t\t\r\nConstructor<?> hashMapConstructor = Class.forName(\"java.util.HashMap\").getConstructor(null);\r\nSystem.out.println(Arrays.toString(hashMapConstructor.getParameterTypes())); \/\/ prints \"[]\"\r\n<\/code><\/pre>\n
                  \u4f7f\u7528\u6784\u9020\u51fd\u6570\u5b9e\u4f8b\u5316\u5bf9\u8c61<\/h3>\n
                  \u6211\u4eec\u53ef\u4ee5\u5728\u6784\u9020\u51fd\u6570\u5bf9\u8c61\u4e0a\u4f7f\u7528newInstance()\u65b9\u6cd5\u6765\u5b9e\u4f8b\u5316\u7c7b\u7684\u65b0\u5b9e\u4f8b\u3002\u7531\u4e8e\u5728\u7f16\u8bd1\u65f6\u6ca1\u6709\u7c7b\u7684\u4fe1\u606f\u65f6\u6211\u4eec\u4f7f\u7528\u53cd\u5c04\uff0c\u56e0\u6b64\u53ef\u4ee5\u5c06\u5176\u8d4b\u7ed9Object\uff0c\u7136\u540e\u8fdb\u4e00\u6b65\u4f7f\u7528\u53cd\u5c04\u6765\u8bbf\u95ee\u5176\u5b57\u6bb5\u548c\u8c03\u7528\u5176\u65b9\u6cd5\u3002<\/p>\n
                  Constructor<?> constructor = Class.forName(\"com.Olivia.reflection.ConcreteClass\").getConstructor(int.class);\r\n\/\/getting constructor parameters\r\nSystem.out.println(Arrays.toString(constructor.getParameterTypes())); \/\/ prints \"[int]\"\r\n\t\t\r\nObject myObj = constructor.newInstance(10);\r\nMethod myObjMethod = myObj.getClass().getMethod(\"method1\", null);\r\nmyObjMethod.invoke(myObj, null); \/\/prints \"Method1 impl.\"\r\n\r\nConstructor<?> hashMapConstructor = Class.forName(\"java.util.HashMap\").getConstructor(null);\r\nSystem.out.println(Arrays.toString(hashMapConstructor.getParameterTypes())); \/\/ prints \"[]\"\r\nHashMap<String,String> myMap = (HashMap<String,String>) hashMapConstructor.newInstance(null);\r\n<\/code><\/pre>\n
                    \u6279\u6ce8\u7684\u53cd\u601d<\/ol>\n
                    Java 1.5\u5f15\u5165\u4e86\u6ce8\u89e3\uff08Annotations\uff09\u7684\u6982\u5ff5\uff0c\u7528\u4e8e\u63d0\u4f9b\u7c7b\u3001\u65b9\u6cd5\u6216\u5b57\u6bb5\u7684\u5143\u6570\u636e\u4fe1\u606f\u3002\u73b0\u5728\u5728Spring\u548cHibernate\u7b49\u6846\u67b6\u4e2d\u5e7f\u6cdb\u4f7f\u7528\u6ce8\u89e3\u3002\u53cd\u5c04API\u4e5f\u8fdb\u884c\u4e86\u6269\u5c55\uff0c\u4ee5\u652f\u6301\u5728\u8fd0\u884c\u65f6\u5206\u6790\u6ce8\u89e3\u3002\u4f7f\u7528\u53cd\u5c04API\uff0c\u6211\u4eec\u53ef\u4ee5\u5206\u6790\u4fdd\u7559\u7b56\u7565\u4e3a\u8fd0\u884c\u65f6\uff08Runtime\uff09\u7684\u6ce8\u89e3\u3002\u6211\u5df2\u7ecf\u5199\u4e86\u4e00\u4efd\u5173\u4e8e\u6ce8\u89e3\u4ee5\u53ca\u5982\u4f55\u4f7f\u7528\u53cd\u5c04API\u89e3\u6790\u6ce8\u89e3\u7684\u8be6\u7ec6\u6559\u7a0b\uff0c\u5efa\u8bae\u60a8\u67e5\u770bJava\u6ce8\u89e3\u6559\u7a0b\u3002\u4ee5\u4e0a\u5c31\u662f\u5173\u4e8eJava\u53cd\u5c04\u793a\u4f8b\u6559\u7a0b\u7684\u5168\u90e8\u5185\u5bb9\u4e86\uff0c\u5e0c\u671b\u60a8\u559c\u6b22\u8fd9\u7bc7\u6559\u7a0b\uff0c\u5e76\u7406\u89e3Java\u53cd\u5c04API\u7684\u91cd\u8981\u6027\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
                    Java\u53cd\u5c04\u63d0\u4f9b\u4e86\u68c0\u67e5\u548c\u4fee\u6539\u5e94\u7528\u7a0b\u5e8f\u8fd0\u884c\u884c\u4e3a\u7684\u80fd\u529b\u3002Java\u4e2d\u7684\u53cd\u5c04\u662f\u6838\u5fc3Java\u4e2d\u7684\u4e00\u4e2a\u9ad8\u7ea7\u4e3b\u9898\u3002\u4f7f\u7528Jav […]<\/p>\n","protected":false},"author":11,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-50737","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"yoast_head":"\nJava\u53cd\u5c04\u793a\u4f8b\u6559\u7a0b - Blog - Silicon Cloud<\/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:\/\/www.silicloud.com\/zh\/blog\/java\u53cd\u5c04\u793a\u4f8b\u6559\u7a0b\/\" \/>\n<meta property=\"og:locale\" content=\"zh_CN\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Java\u53cd\u5c04\u793a\u4f8b\u6559\u7a0b\" \/>\n<meta property=\"og:description\" content=\"Java\u53cd\u5c04\u63d0\u4f9b\u4e86\u68c0\u67e5\u548c\u4fee\u6539\u5e94\u7528\u7a0b\u5e8f\u8fd0\u884c\u884c\u4e3a\u7684\u80fd\u529b\u3002Java\u4e2d\u7684\u53cd\u5c04\u662f\u6838\u5fc3Java\u4e2d\u7684\u4e00\u4e2a\u9ad8\u7ea7\u4e3b\u9898\u3002\u4f7f\u7528Jav […]\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.silicloud.com\/zh\/blog\/java\u53cd\u5c04\u793a\u4f8b\u6559\u7a0b\/\" \/>\n<meta property=\"og:site_name\" content=\"Blog - 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