{"id":6888,"date":"2022-08-08T10:14:33","date_gmt":"2022-08-08T02:14:33","guid":{"rendered":"http:\/\/123.57.164.21\/?p=6888"},"modified":"2022-08-08T13:07:39","modified_gmt":"2022-08-08T05:07:39","slug":"java%e4%bd%bf%e7%94%a8%e5%8f%8d%e5%b0%84%e5%88%9b%e5%bb%ba%e8%a2%abprivate%e4%bf%ae%e9%a5%b0%e7%9a%84%e6%9e%84%e9%80%a0%e5%87%bd%e6%95%b0%e5%af%b9%e8%b1%a1","status":"publish","type":"post","link":"https:\/\/92it.top\/?p=6888","title":{"rendered":"Java\u4f7f\u7528\u53cd\u5c04\u521b\u5efa\u88abprivate\u4fee\u9970\u7684\u6784\u9020\u51fd\u6570\u5bf9\u8c61"},"content":{"rendered":"\n

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public class PrivateTest {\n\n    private int num;\n\n    private PrivateTest() {\n          num = 1\n    }\n\n   private PrivateTest(int num) {\n          this.num = num\n   }\n\n    public void output() {\n        System.out.print(\"string is : me\" );\n    }\n}<\/pre>\n\n\n\n
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public static void main(String[] args) {\n    try {\n        Class clz = Class.forName(\"reflectDemo.PrivateTest\");\n        Object obj = clz.newInstance();\n        if (obj instanceof PrivateTest){\n            PrivateTest test = (PrivateTest) obj;\n            test.output();\n        }\n    } catch (Exception e) {\n        e.printStackTrace();\n    }\n}<\/pre>\n\n\n\n
\u8fd0\u884c\u7a0b\u5e8f\u4f1a\u53d1\u73b0\u62a5\u9519\uff1a<\/p>\n\n\n\n
\"\"<\/figure><\/div>\n\n\n\n
\u53ef\u4ee5\u770b\u5230\u8fd9\u79cd\u65b9\u5f0f\u884c\u4e0d\u901a\uff0c\u90a3\u4e48\u6211\u4eec\u7528Constructor\u6765\u8bd5\u8bd5\u770b\u884c\u4e0d\u884c\u5462<\/p>\n\n\n\n
public static void main(String[] args) {\n    try {\n        Class clz = Class.forName(\"reflectDemo.PrivateTest\");\n        Constructor constructor = clz.getDeclaredConstructor();\n        Object obj = constructor.newInstance();\n        if (obj instanceof PrivateTest){\n            PrivateTest test = (PrivateTest) obj;\n            test.output();\n        }\n    } catch (Exception e) {\n        e.printStackTrace();\n    }\n}<\/pre>\n\n\n\n
\u8fd0\u884c\u7a0b\u5e8f\u540c\u6837\u4e5f\u4f1a\u62a5\u9519\uff1a<\/p>\n\n\n\n
\"\"<\/figure><\/div>\n\n\n\n
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    constructor.setAccessible(true);<\/pre>\n\n\n\n
public static void main(String[] args) {\n    try {\n        Class clz = Class.forName(\"reflectDemo.PrivateTest\");\n        \/\/ getDeclaredConstructor\u4e0d\u52a0\u53c2\u6570\u7684\u8bdd\uff0c\u662f\u53d6\u5f97\u65e0\u53c2\u6570\u6784\u9020\u5668\n        Constructor constructor = clz.getDeclaredConstructor();\n        \/\/ \u5982\u679c\u60f3\u53d6\u5f97\u6709\u53c2\u6570\u7684\u6784\u9020\u5668\uff0c\u9700\u8981\u628a\u6307\u5b9a\u53c2\u6570\u7684Class\u5bf9\u8c61\u52a0\u4e0a\n        \/\/ Constructor constructor = clz.getDeclaredConstructor(int.class);\n        constructor.setAccessible(true);\n        Object obj = constructor.newInstance();\n        if (obj instanceof PrivateTest){\n            PrivateTest test = (PrivateTest) obj;\n            test.output();\n        }\n    } catch (Exception e) {\n        e.printStackTrace();\n    }\n}\n<\/pre>\n\n\n\n
\u52a0\u4e0a\u8fd9\u884c\u4ee3\u7801\u7684\u542b\u4e49\u8868\u793a\u6211\u4eec\u7684constructor\u5bf9\u8c61\u80fd\u591f\u8bbf\u95ee\u6211\u4eec\u7684private\u4fee\u9970\u7684\u6784\u9020\u51fd\u6570\uff0c\u8fd0\u884c\u7a0b\u5e8f\u770b\u770b\u53d8\u5316\uff1a<\/p>\n\n\n\n
\"\"<\/figure><\/div>\n\n\n\n
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