{"id":10459,"date":"2023-11-28T21:35:18","date_gmt":"2023-11-28T13:35:18","guid":{"rendered":"https:\/\/wx.kaifamiao.info\/?p=10459"},"modified":"2023-12-07T11:28:54","modified_gmt":"2023-12-07T03:28:54","slug":"jvm-zhong-shuang-qin-wei-pai-ji-zhi-ke-yi-bei-wei","status":"publish","type":"post","link":"http:\/\/wx.kaifamiao.info\/index.php\/2023\/11\/28\/jvm-zhong-shuang-qin-wei-pai-ji-zhi-ke-yi-bei-wei\/","title":{"rendered":"JVM\u4e2d\u53cc\u4eb2\u59d4\u6d3e\u673a\u5236\u53ef\u4ee5\u88ab\u8fdd\u80cc\u5417\uff1f\u8bf7\u4e3e\u4f8b\u8bf4\u660e\uff1f"},"content":{"rendered":"<p>\u867d\u7136 Java \u7684\u7c7b\u52a0\u8f7d\u673a\u5236\u4e2d\u4f7f\u7528\u4e86\u53cc\u4eb2\u59d4\u6d3e\u673a\u5236\uff0c\u4f46\u662f\u5728\u4e00\u4e9b\u7279\u6b8a\u60c5\u51b5\u4e0b\uff0c\u662f\u53ef\u4ee5\u6253\u7834\u53cc\u4eb2\u59d4\u6d3e\u673a\u5236\u7684\u3002\u8fd9\u901a\u5e38\u662f\u901a\u8fc7\u4f7f\u7528\u4e00\u4e9b\u7279\u6b8a\u7684\u7c7b\u52a0\u8f7d\u5668\u6765\u5b9e\u73b0\u7684\u3002\u4ee5\u4e0b\u662f\u4e00\u4e2a\u7b80\u5355\u7684\u4f8b\u5b50\u8bf4\u660e\u5982\u4f55\u6253\u7834\u53cc\u4eb2\u59d4\u6d3e\u673a\u5236\uff1a<\/p>\n<pre><code class=\"language-java\">\/\/ \u81ea\u5b9a\u4e49\u7c7b\u52a0\u8f7d\u5668\uff0c\u7ee7\u627f\u81eaClassLoader\npublic class CustomClassLoader extends ClassLoader {\n    @Override\n    public Class&lt;?&gt; loadClass(String name) throws ClassNotFoundException {\n        \/\/ \u5982\u679c\u7c7b\u540d\u4ee5\u7279\u5b9a\u524d\u7f00\u5f00\u5934\uff0c\u5219\u4f7f\u7528\u81ea\u5b9a\u4e49\u52a0\u8f7d\u65b9\u5f0f\n        if (name.startsWith(&quot;com.example&quot;)) {\n            return customLoadClass(name);\n        }\n        \/\/ \u5426\u5219\u4ecd\u7136\u4f7f\u7528\u53cc\u4eb2\u59d4\u6d3e\u673a\u5236\n        return super.loadClass(name);\n    }\n\n    private Class&lt;?&gt; customLoadClass(String name) throws ClassNotFoundException {\n        try {\n            \/\/ \u901a\u8fc7\u81ea\u5b9a\u4e49\u65b9\u5f0f\u52a0\u8f7d\u7c7b\uff0c\u4f8b\u5982\u4ece\u7279\u5b9a\u4f4d\u7f6e\u52a0\u8f7d\n            byte[] classData = \/\/ \u4ece\u7279\u5b9a\u4f4d\u7f6e\u8bfb\u53d6\u7c7b\u7684\u5b57\u8282\u7801\n            return defineClass(name, classData, 0, classData.length);\n        } catch (IOException e) {\n            throw new ClassNotFoundException(name, e);\n        }\n    }\n}\n\npublic class Main {\n    public static void main(String[] args) throws Exception {\n        \/\/ \u4f7f\u7528\u81ea\u5b9a\u4e49\u7c7b\u52a0\u8f7d\u5668\u52a0\u8f7d\u7c7b\n        CustomClassLoader customClassLoader = new CustomClassLoader();\n        Class&lt;?&gt; customClass = customClassLoader.loadClass(&quot;com.example.CustomClass&quot;);\n\n        \/\/ \u521b\u5efa\u5b9e\u4f8b\u5e76\u8c03\u7528\u65b9\u6cd5\n        Object instance = customClass.newInstance();\n        customClass.getMethod(&quot;doSomething&quot;).invoke(instance);\n    }\n}\n<\/code><\/pre>\n<p>\u5728\u4e0a\u8ff0\u4f8b\u5b50\u4e2d\uff0c<code>CustomClassLoader<\/code> \u81ea\u5b9a\u4e49\u4e86\u52a0\u8f7d\u7c7b\u7684\u65b9\u5f0f\uff0c\u5f53\u52a0\u8f7d\u7684\u7c7b\u540d\u4ee5\u7279\u5b9a\u524d\u7f00\u5f00\u5934\u65f6\uff0c\u4f7f\u7528\u81ea\u5b9a\u4e49\u52a0\u8f7d\u65b9\u5f0f\u52a0\u8f7d\uff0c\u5426\u5219\u4ecd\u7136\u4f7f\u7528\u53cc\u4eb2\u59d4\u6d3e\u673a\u5236\u3002\u8fd9\u6837\u5c31\u6253\u7834\u4e86\u53cc\u4eb2\u59d4\u6d3e\u673a\u5236\u7684\u9650\u5236\u3002<\/p>\n<p>\u9700\u8981\u6ce8\u610f\u7684\u662f\uff0c\u6253\u7834\u53cc\u4eb2\u59d4\u6d3e\u673a\u5236\u53ef\u80fd\u5bfc\u81f4\u7c7b\u52a0\u8f7d\u7684\u6df7\u4e71\u548c\u51b2\u7a81\uff0c\u56e0\u6b64\u5728\u6b63\u5e38\u60c5\u51b5\u4e0b\uff0c\u63a8\u8350\u5c3d\u91cf\u9075\u5faa\u53cc\u4eb2\u59d4\u6d3e\u673a\u5236\u3002\u6253\u7834\u53cc\u4eb2\u59d4\u6d3e\u673a\u5236\u901a\u5e38\u662f\u5728\u4e00\u4e9b\u7279\u6b8a\u9700\u6c42\u4e0b\uff0c\u5982\u70ed\u90e8\u7f72\u3001\u52a8\u6001\u52a0\u8f7d\u7b49\u60c5\u51b5\u4e0b\u4f7f\u7528\uff0c\u800c\u4e14\u9700\u8981\u8c28\u614e\u5904\u7406\u7c7b\u52a0\u8f7d\u7684\u4e00\u81f4\u6027\u548c\u5b89\u5168\u6027\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u867d\u7136 Java \u7684\u7c7b\u52a0\u8f7d\u673a\u5236\u4e2d\u4f7f\u7528\u4e86\u53cc\u4eb2\u59d4\u6d3e\u673a\u5236\uff0c\u4f46\u662f\u5728\u4e00\u4e9b\u7279\u6b8a\u60c5\u51b5\u4e0b\uff0c\u662f\u53ef\u4ee5\u6253\u7834\u53cc\u4eb2\u59d4\u6d3e\u673a\u5236\u7684\u3002\u8fd9\u901a\u5e38\u662f\u901a\u8fc7 [&hellip;]<\/p>\n","protected":false},"author":9,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[119],"tags":[],"class_list":["post-10459","post","type-post","status-publish","format-standard","hentry","category-jvm"],"_links":{"self":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/10459","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/users\/9"}],"replies":[{"embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/comments?post=10459"}],"version-history":[{"count":2,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/10459\/revisions"}],"predecessor-version":[{"id":16843,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/10459\/revisions\/16843"}],"wp:attachment":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/media?parent=10459"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/categories?post=10459"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/tags?post=10459"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}