{"id":10067,"date":"2023-11-28T21:25:48","date_gmt":"2023-11-28T13:25:48","guid":{"rendered":"https:\/\/wx.kaifamiao.info\/?p=10067"},"modified":"2023-12-07T10:47:45","modified_gmt":"2023-12-07T02:47:45","slug":"jvm-zhong-nei-cun-mo-xing-le-jie-ma","status":"publish","type":"post","link":"http:\/\/wx.kaifamiao.info\/index.php\/2023\/11\/28\/jvm-zhong-nei-cun-mo-xing-le-jie-ma\/","title":{"rendered":"JVM\u4e2d\u5185\u5b58\u6a21\u578b\u4e86\u89e3\u5417\uff1f"},"content":{"rendered":"<p>Java\u865a\u62df\u673a\u7684\u5185\u5b58\u6a21\u578b\uff08Java Memory Model\uff0c\u7b80\u79f0JMM\uff09\u5b9a\u4e49\u4e86\u591a\u7ebf\u7a0b\u7a0b\u5e8f\u4e2d\u5404\u4e2a\u7ebf\u7a0b\u4e4b\u95f4\u5982\u4f55\u8bbf\u95ee\u5171\u4eab\u5185\u5b58\u7684\u89c4\u5219\uff0c\u4ee5\u53ca\u5728\u4f55\u65f6\u4ee5\u53ca\u5982\u4f55\u540c\u6b65\u5bf9\u5171\u4eab\u53d8\u91cf\u7684\u8bbf\u95ee\u3002JMM\u4e3b\u8981\u5173\u6ce8\u4ee5\u4e0b\u51e0\u4e2a\u65b9\u9762\uff1a<\/p>\n<h3><a id=\"1%E4%B8%BB%E5%86%85%E5%AD%98%E5%92%8C%E5%B7%A5%E4%BD%9C%E5%86%85%E5%AD%98%EF%BC%9A\" class=\"anchor\" aria-hidden=\"true\"><span class=\"octicon octicon-link\"><\/span><\/a>1. \u4e3b\u5185\u5b58\u548c\u5de5\u4f5c\u5185\u5b58\uff1a<\/h3>\n<ul>\n<li>\n<strong>\u4e3b\u5185\u5b58\uff08Main Memory\uff09\uff1a<\/strong> \u6240\u6709\u7ebf\u7a0b\u5171\u4eab\u7684\u5185\u5b58\u533a\u57df\uff0c\u5305\u542b\u6240\u6709\u7684\u5171\u4eab\u53d8\u91cf\u3002\n<\/li>\n<li>\n<strong>\u5de5\u4f5c\u5185\u5b58\uff08Working Memory\uff09\uff1a<\/strong> \u6bcf\u4e2a\u7ebf\u7a0b\u79c1\u6709\u7684\u5185\u5b58\u533a\u57df\uff0c\u5b58\u50a8\u4e86\u8be5\u7ebf\u7a0b\u4f7f\u7528\u5230\u7684\u53d8\u91cf\u7684\u526f\u672c\u3002\n<\/li>\n<\/ul>\n<h3><a id=\"2%E5%86%85%E5%AD%98%E5%B1%8F%E9%9A%9C%EF%BC%88-memory-barriers%EF%BC%89%EF%BC%9A\" class=\"anchor\" aria-hidden=\"true\"><span class=\"octicon octicon-link\"><\/span><\/a>2. \u5185\u5b58\u5c4f\u969c\uff08Memory Barriers\uff09\uff1a<\/h3>\n<ul>\n<li>\n<strong>\u8bfb\u5c4f\u969c\uff08Read Barrier\uff09\uff1a<\/strong> \u7528\u4e8e\u786e\u4fdd\u4e00\u4e2a\u7ebf\u7a0b\u8bfb\u53d6\u4e00\u4e2a\u5171\u4eab\u53d8\u91cf\u7684\u503c\u65f6\uff0c\u80fd\u591f\u770b\u5230\u5176\u4ed6\u7ebf\u7a0b\u5bf9\u8be5\u53d8\u91cf\u5728\u4e3b\u5185\u5b58\u4e2d\u7684\u6700\u65b0\u5199\u5165\u3002\n<\/li>\n<li>\n<strong>\u5199\u5c4f\u969c\uff08Write Barrier\uff09\uff1a<\/strong> \u7528\u4e8e\u786e\u4fdd\u4e00\u4e2a\u7ebf\u7a0b\u5199\u5165\u4e00\u4e2a\u5171\u4eab\u53d8\u91cf\u7684\u503c\u65f6\uff0c\u5bf9\u5176\u4ed6\u7ebf\u7a0b\u80fd\u591f\u7acb\u5373\u53ef\u89c1\u3002\n<\/li>\n<\/ul>\n<h3><a id=\"3%E5%8E%9F%E5%AD%90%E6%80%A7%E3%80%81%E5%8F%AF%E8%A7%81%E6%80%A7%E3%80%81%E6%9C%89%E5%BA%8F%E6%80%A7%EF%BC%9A\" class=\"anchor\" aria-hidden=\"true\"><span class=\"octicon octicon-link\"><\/span><\/a>3. \u539f\u5b50\u6027\u3001\u53ef\u89c1\u6027\u3001\u6709\u5e8f\u6027\uff1a<\/h3>\n<ul>\n<li>\n<strong>\u539f\u5b50\u6027\uff08Atomicity\uff09\uff1a<\/strong> \u6307\u7684\u662f\u4e00\u4e2a\u64cd\u4f5c\u662f\u4e0d\u53ef\u4e2d\u65ad\u7684\u3002\u8981\u4e48\u8fd9\u4e2a\u64cd\u4f5c\u5168\u90e8\u6267\u884c\u6210\u529f\uff0c\u8981\u4e48\u5168\u90e8\u4e0d\u6267\u884c\u3002\n<\/li>\n<li>\n<strong>\u53ef\u89c1\u6027\uff08Visibility\uff09\uff1a<\/strong> \u6307\u7684\u662f\u5f53\u4e00\u4e2a\u7ebf\u7a0b\u4fee\u6539\u4e86\u5171\u4eab\u53d8\u91cf\u7684\u503c\uff0c\u5176\u4ed6\u7ebf\u7a0b\u80fd\u591f\u7acb\u5373\u770b\u5230\u8fd9\u4e2a\u4fee\u6539\u3002\n<\/li>\n<li>\n<strong>\u6709\u5e8f\u6027\uff08Ordering\uff09\uff1a<\/strong> \u6307\u7684\u662f\u7a0b\u5e8f\u6267\u884c\u7684\u987a\u5e8f\u6309\u7167\u4ee3\u7801\u7684\u5148\u540e\u987a\u5e8f\u6765\u6267\u884c\u3002\n<\/li>\n<\/ul>\n<h3><a id=\"4-happens-before%E8%A7%84%E5%88%99%EF%BC%9A\" class=\"anchor\" aria-hidden=\"true\"><span class=\"octicon octicon-link\"><\/span><\/a>4. Happens-Before\u89c4\u5219\uff1a<\/h3>\n<ul>\n<li>\n<strong>\u7a0b\u5e8f\u6b21\u5e8f\u89c4\u5219\uff08Program Order Rule\uff09\uff1a<\/strong> \u5728\u4e00\u4e2a\u7ebf\u7a0b\u5185\uff0c\u6309\u7167\u7a0b\u5e8f\u4ee3\u7801\u7684\u987a\u5e8f\uff0c\u524d\u9762\u7684\u64cd\u4f5c Happens-Before \u4e8e\u540e\u9762\u7684\u64cd\u4f5c\u3002\n<\/li>\n<li>\n<strong>\u76d1\u89c6\u5668\u9501\u89c4\u5219\uff08Monitor Lock Rule\uff09\uff1a<\/strong> \u5bf9\u4e00\u4e2a\u9501\u7684\u89e3\u9501 Happens-Before \u4e8e\u968f\u540e\u5bf9\u8fd9\u4e2a\u9501\u7684\u52a0\u9501\u3002\n<\/li>\n<li>\n<strong>volatile\u53d8\u91cf\u89c4\u5219\uff08Volatile Variable Rule\uff09\uff1a<\/strong> \u5bf9\u4e00\u4e2a volatile \u5b57\u6bb5\u7684\u5199\u64cd\u4f5c Happens-Before \u4e8e\u4efb\u610f\u540e\u7eed\u5bf9\u8fd9\u4e2a volatile \u5b57\u6bb5\u7684\u8bfb\u64cd\u4f5c\u3002\n<\/li>\n<li>\n<strong>\u7ebf\u7a0b\u542f\u52a8\u89c4\u5219\uff08Thread Start Rule\uff09\uff1a<\/strong> \u7ebf\u7a0b A \u542f\u52a8\u7ebf\u7a0b B\uff0c\u90a3\u4e48\u7ebf\u7a0b B \u7684\u64cd\u4f5c Happens-Before \u4e8e\u7ebf\u7a0b A \u7684\u540e\u7eed\u64cd\u4f5c\u3002\n<\/li>\n<li>\n<strong>\u7ebf\u7a0b\u7ec8\u6b62\u89c4\u5219\uff08Thread Termination Rule\uff09\uff1a<\/strong> \u7ebf\u7a0b A \u7b49\u5f85\u7ebf\u7a0b B \u7ec8\u6b62\uff0c\u90a3\u4e48\u7ebf\u7a0b B \u7684\u7ec8\u6b62\u64cd\u4f5c Happens-Before \u4e8e\u7ebf\u7a0b A \u7684\u540e\u7eed\u64cd\u4f5c\u3002\n<\/li>\n<\/ul>\n<h3><a id=\"5-final%E5%9F%9F%E8%A7%84%E5%88%99%EF%BC%9A\" class=\"anchor\" aria-hidden=\"true\"><span class=\"octicon octicon-link\"><\/span><\/a>5. final\u57df\u89c4\u5219\uff1a<\/h3>\n<ul>\n<li><strong>final\u57df\u89c4\u5219\uff08Final Field Rule\uff09\uff1a<\/strong> \u5728\u6784\u9020\u51fd\u6570\u5185\u5bf9\u4e00\u4e2a final \u57df\u7684\u5199\u64cd\u4f5c\uff0c\u4e0e\u968f\u540e\u5728\u6784\u9020\u51fd\u6570\u5916\uff08\u5305\u62ec\u5176\u4ed6\u7ebf\u7a0b\u4e2d\uff09\u5bf9\u8fd9\u4e2a final \u57df\u7684\u8bfb\u64cd\u4f5c\uff0c\u4fdd\u8bc1\u80fd\u770b\u5230\u6784\u9020\u51fd\u6570\u5185\u5bf9 final \u57df\u7684\u5199\u5165\u3002<\/li>\n<\/ul>\n<p>JMM\u901a\u8fc7\u4e0a\u8ff0\u89c4\u5219\u6765\u4fdd\u8bc1\u591a\u7ebf\u7a0b\u7a0b\u5e8f\u4e2d\u7684\u5185\u5b58\u8bbf\u95ee\u64cd\u4f5c\u7684\u6b63\u786e\u6027\u3002\u4e86\u89e3JMM\u5bf9\u4e8e\u5199\u51fa\u6b63\u786e\u3001\u9ad8\u6548\u7684\u591a\u7ebf\u7a0b\u7a0b\u5e8f\u975e\u5e38\u91cd\u8981\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Java\u865a\u62df\u673a\u7684\u5185\u5b58\u6a21\u578b\uff08Java Memory Model\uff0c\u7b80\u79f0JMM\uff09\u5b9a\u4e49\u4e86\u591a\u7ebf\u7a0b\u7a0b\u5e8f\u4e2d\u5404\u4e2a\u7ebf\u7a0b\u4e4b\u95f4\u5982\u4f55\u8bbf [&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-10067","post","type-post","status-publish","format-standard","hentry","category-jvm"],"_links":{"self":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/10067","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=10067"}],"version-history":[{"count":2,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/10067\/revisions"}],"predecessor-version":[{"id":16795,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/10067\/revisions\/16795"}],"wp:attachment":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/media?parent=10067"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/categories?post=10067"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/tags?post=10067"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}