{"id":825,"date":"2020-06-29T22:39:31","date_gmt":"2020-06-29T14:39:31","guid":{"rendered":"https:\/\/www.zhuyanbin.com\/?p=825"},"modified":"2020-07-01T23:46:42","modified_gmt":"2020-07-01T15:46:42","slug":"java%e5%bb%b6%e8%bf%9f%e5%88%9d%e5%a7%8b%e5%8c%96%e5%8c%96%e7%9a%84%e6%ad%a3%e7%a1%ae%e6%96%b9%e5%bc%8f","status":"publish","type":"post","link":"https:\/\/www.yanbin888.com\/?p=825","title":{"rendered":"Java\u5ef6\u8fdf\u521d\u59cb\u5316\u7684\u6b63\u786e\u65b9\u5f0f"},"content":{"rendered":"\n<p>\u5b9e\u4f8b\u5316\u5bf9\u8c61\u5728JVM\u4e2d\u5b9e\u9645\u4e0a\u5305\u542b\u5982\u4e0b\u6307\u4ee4\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\"><li>\u5206\u914d\u5185\u5b58\u7a7a\u95f4<\/li><li>\u521d\u59cb\u5316\u5bf9\u8c61<\/li><li>\u5c06instance\u6307\u5411\u521a\u624d\u5206\u914d\u597d\u7684\u5185\u5b58\u7a7a\u95f4\u5730\u5740<\/li><\/ol>\n\n\n\n<p>\u4e0a\u8ff0\u6b65\u9aa4\u5728\u5355\u7ebf\u7a0b\u4e2d\u662f\u6ca1\u95ee\u9898\u7684\u3002JVM\u5728\u6307\u4ee4\u91cd\u6392\u5e8f\u4e5f\u4e0d\u4f1a\u5f71\u54cd\u5230\u5355\u7ebf\u7a0b\u7684\u6267\u884c\u987a\u5e8f\uff0c\u4f46\u662f\u5728\u591a\u7ebf\u7a0b\u73af\u5883\u4e0b\u5c31\u4f1a\u56e0\u4e3a\u91cd\u6392\u5e8f\u5bfc\u81f4\u51fa\u73b0\u4f7f\u7528\u672a\u88ab\u521d\u59cb\u5316\u5b8c\u6210\u7684\u5bf9\u8c61\uff0c\u6307\u4ee4\u4f1a\u88ab\u91cd\u6392\u5e8f\u4e3a\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\"><li>\u5206\u914d\u5185\u5b58\u7a7a\u95f4<\/li><li>\u5c06instance\u6307\u5411\u521a\u5206\u914d\u597d\u7684\u5185\u5b58\u7a7a\u95f4\u5730\u5740<\/li><li>\u521d\u59cb\u5316\u5bf9\u8c61<\/li><\/ol>\n\n\n\n<p>\u5982\u679c\u7ebf\u7a0b1\u6267\u884c\u5230\u4e86\u4e0a\u8ff0\u7684\u6b65\u9aa42\uff0c\u7ebf\u7a0b2\u6267\u884c\u5c31\u4f1a\u4f7f\u7528\u672a\u88ab\u521d\u59cb\u5316\u5b8c\u6210\u7684\u5bf9\u8c61\u3002<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>\u5e26\u53cc\u91cd\u68c0\u67e5\u7684\u5ef6\u8fdf\u521d\u59cb\u5316<\/li><\/ul>\n\n\n\n<pre class=\"wp-block-preformatted\">public class DoubleCheckedInstance {\n    private volatile static Instance <em>instance<\/em>;\n    public static Instance getInstance() {\n        if (<em>instance <\/em>== null) {\n            synchronized (DoubleCheckedInstance.class) {\n                if (<em>instance <\/em>== null) {\n                    <em>instance <\/em>= new Instance();\n                }\n            }\n        }\n\n        return <em>instance<\/em>;\n    }\n}<\/pre>\n\n\n\n<p>\u5173\u952e\u70b9\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\">private <strong><span class=\"has-inline-color has-vivid-red-color\">volatile<\/span><\/strong> static Instance <em>instance<\/em>;<\/pre>\n\n\n\n<p>\u5982\u679c\u6ca1\u6709<strong>volatile<\/strong>\u5173\u952e\u5b57\uff0c\u5219\u5728\u5b9e\u4f8b\u5316Instance\u5bf9\u8c61\u65f6\u4f1a\u51fa\u73b0\u6307\u4ee4\u91cd\u6392\u5e8f\uff0c\u4ece\u800c\u5bfc\u81f4\u5728\u591a\u7ebf\u7a0b\u73af\u5883\u4e0b\u4f7f\u7528\u4e86\u672a\u88ab\u521d\u59cb\u5316\u5b8c\u6210\u7684\u5bf9\u8c61\u3002<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>\u57fa\u4e8e\u7c7b\u5ef6\u8fdf\u521d\u59cb\u5316<\/li><\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>public class InstanceFactory {\n    private static class InstanceHolder {\n        public static Instance instance = new Instance();\n    }\n    \n    public static Instance getInstance() {\n        return InstanceHolder.instance;\n    }\n}<\/code><\/pre>\n\n\n\n<p>JVM\u5728\u7c7b\u7684\u521d\u59cb\u5316\u9636\u6bb5\uff08\u5373\u5728Class\u88ab\u52a0\u8f7d\u540e\uff0c\u4e14\u88ab\u7ebf\u7a0b\u4f7f\u7528\u4e4b\u524d\uff09\uff0c\u4f1a\u6267\u884c\u7c7b\u7684\u521d\u59cb\u5316\u3002\u5728\u6267\u884c\u7c7b\u7684\u521d\u59cb\u5316\u671f\u95f4\uff0cJVM\u4f1a\u53bb\u83b7\u53d6\u4e00\u4e2a\u9501\u3002\u8fd9\u4e2a\u9501\u53ef\u4ee5\u540c\u6b65\u591a\u4e2a\u7ebf\u7a0b\u5bf9\u540c\u4e00\u4e2a\u7c7b\u7684\u521d\u59cb\u5316\u3002<\/p>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter size-large is-resized\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.zhuyanbin.com\/wp-content\/uploads\/2020\/06\/image-1024x663.jpg\" alt=\"\" class=\"wp-image-832\" width=\"580\" height=\"375\" srcset=\"https:\/\/www.yanbin888.com\/wp-content\/uploads\/2020\/06\/image-1024x663.jpg 1024w, https:\/\/www.yanbin888.com\/wp-content\/uploads\/2020\/06\/image-300x194.jpg 300w, https:\/\/www.yanbin888.com\/wp-content\/uploads\/2020\/06\/image-768x498.jpg 768w, https:\/\/www.yanbin888.com\/wp-content\/uploads\/2020\/06\/image.jpg 1130w\" sizes=\"auto, (max-width: 580px) 100vw, 580px\" \/><figcaption>\u4e24\u4e2a\u7ebf\u7a0b\u5e76\u53d1\u6267\u884c\u7684\u793a\u610f\u56fe<\/figcaption><\/figure><\/div>\n\n\n\n<p>\u53c2\u8003\u8d44\u6599\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\"><li>\u65b9\u817e\u98de,\u9b4f\u9e4f,\u7a0b\u6653\u660e.\u300aJava\u5e76\u53d1\u7f16\u7a0b\u7684\u827a\u672f\u300b\u673a\u68b0\u5de5\u4e1a\u51fa\u7248\u793e ISBN\uff1a9787111508243<\/li><\/ol>\n\n\n\n<p><\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5b9e\u4f8b\u5316\u5bf9\u8c61\u5728JVM\u4e2d\u5b9e\u9645\u4e0a\u5305\u542b\u5982\u4e0b\u6307\u4ee4\uff1a \u5206\u914d\u5185\u5b58\u7a7a\u95f4 \u521d\u59cb\u5316\u5bf9\u8c61 \u5c06instance\u6307\u5411\u521a\u624d\u5206\u914d\u597d\u7684\u5185\u5b58\u7a7a\u95f4 <span class=\"ellipsis\">&hellip;<\/span> <span 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