ConcurrentHashMap\u548c Hashtable \u7684\u533a\u522b\u4e3b\u8981\u4f53\u73b0\u5728\u5b9e\u73b0\u7ebf\u7a0b\u5b89\u5168\u7684\u65b9\u5f0f\u4e0a\u4e0d\u540c
\n\u5e95\u5c42\u6570\u636e\u7ed3\u6784:
\n1\u3001JDK1.7\u7684 ConcurrentHashMap\u5e95\u5c42\u91c7\u7528\u5206\u6bb5\u7684\u6570\u7ec4+\u94fe\u8868\u5b9e\u73b0\uff0cJDK1.8\u91c7\u7528\u7684\u6570\u636e\u7ed3\u6784\u8ddfHashMap1.8\u7684\u7ed3\u6784\u4e00\u6837\uff0c\u6570\u7ec4+\u94fe\u8868\/\u7ea2\u9ed1\u4e8c\u53c9\u6811\u3002
\n2\u3001HashTable\u548c JDK1.8\u4e4b\u524d\u7684 HashMap \u7684\u5e95\u5c42\u6570\u636e\u7ed3\u6784\u7c7b\u4f3c\uff0c\u90fd\u662f\u91c7\u7528\u6570\u7ec4+\u94fe\u8868\u7684\u5f62\u5f0f\uff0c\u6570\u7ec4\u662f HashMap \u7684\u4e3b\u4f53\uff0c\u94fe\u8868\u5219\u662f\u4e3b\u8981\u4e3a\u4e86\u89e3\u51b3\u54c8\u5e0c\u51b2\u7a81\u800c\u5b58\u5728\u7684;
\n\u5b9e\u73b0\u7ebf\u7a0b\u5b89\u5168\u7684\u65b9\u5f0f\uff08\u91cd\u8981\uff09:
\n1\u3001\u5728 JDK1.7\u7684\u65f6\u5019\uff0cConcurrentHachMap(\u5206\u6bb5\u9501)\u5bf9\u6574\u4e2a\u6876\u6570\u7ec4\u8fdb\u884c\u4e86\u5206\u5272\u5206\u6bb5(Segment),\u6bcf\u4e00\u628a\u9501\u53ea\u9501\u5bb9\u5668\u5176\u4e2d\u4e00\u90e8\u5206\u6570\u636e\uff0c\u591a\u7ebf\u7a0b\u8bbf\u95ee\u5bb9\u5668\u91cc\u4e0d\u540c\u6570\u636e\u6bb5\u7684\u6570\u636e\uff0c\u5c31\u4e0d\u4f1a\u5b58\u5728\u9501\u7ade\u4e89,\u63d0\u9ad8\u5e76\u53d1\u8bbf\u95ee\u7387\u3002
\n\u5230\u4e86JDK1.8\u7684\u65f6\u5019\u5df2\u7ecf\u6452\u5f03\u4e86Segment\u7684\u6982\u5ff5\uff0c\u800c\u662f\u76f4\u63a5\u7528 Node \u6570\u7ec4+\u94fe\u8868+\u7ea2\u9ed1\u6811\u7684\u6570\u636e\u7ed3\u6784\u6765\u5b9e\u73b0\uff0c\u5e76\u53d1\u63a7\u5236\u4f7f\u7528synchronized\u548cCAS\u6765\u64cd\u4f5c\u3002(JDK1.6\u4ee5\u540e\u5bf9synchronized\u9501\u505a\u4e86\u5f88\u591a\u4f18\u5316)\u6574\u4e2a\u770b\u8d77\u6765\u5c31\u50cf\u662f\u4f18\u5316\u8fc7\u4e14\u7ebf\u7a0b\u5b89\u5168\u7684 HashMap\uff0c\u867d\u7136\u5728JDK1.8\u4e2d\u8fd8\u80fd\u770b\u5230 Segment\u7684\u6570\u636e\u7ed3\u6784\uff0c\u4f46\u662f\u5df2\u7ecf\u7b80\u5316\u4e86\u5c5e\u6027,\u53ea\u662f\u4e3a\u4e86\u517c\u5bb9\u65e7\u7248\u672c;
\n2\u3001HashTable(\u540c\u6b65\u9501):\u4f7f\u7528synchronized\u6765\u4fdd\u8bc1\u7ebf\u7a0b\u5b89\u5168\uff0c\u6548\u7387\u975e\u5e38\u4f4e\u4e0b\u3002\u5f53\u4e00\u4e2a\u7ebf\u7a0b\u8bbf\u95ee\u540c\u6b65\u65b9\u6cd5\u65f6,\u5176\u4ed6\u7ebf\u7a0b\u4e5f\u8bbf\u95ee\u540c\u6b65\u65b9\u6cd5\uff0c\u53ef\u80fd\u4f1a\u8fdb\u5165\u963b\u585e\u6216\u8f6e\u8be2\u72b6\u6001\uff0c\u5982\u4f7f\u7528 put\u6dfb\u52a0\u5143\u7d20\uff0c\u53e6\u4e00\u4e2a\u7ebf\u7a0b\u4e0d\u80fd\u4f7f\u7528put\u6dfb\u52a0\u5143\u7d20\uff0c\u4e5f\u4e0d\u80fd\u4f7f\u7528get\uff0c\u7ade\u4e89\u4f1a\u8d8a\u6765\u8d8a\u6fc0\u70c8\u6548\u7387\u8d8a\u4f4e\u3002
\n\u603b\u7ed3:
\n1\u3001HashTable\u5c31\u662f\u5b9e\u73b0\u4e86HashMap \u52a0\u4e0a\u4e86 synchronized\uff0c\u800cConcurrentHashMap\u5e95\u5c42\u91c7\u7528\u5206\u6bb5\u7684\u6570\u7ec4+\u94fe\u8868\u5b9e\u73b0\uff0c\u7ebf\u7a0b\u5b89\u5168
\n2\u3001ConcurrentHashMap \u901a\u8fc7\u628a\u6574\u4e2aMap\u5206\u4e3aN\u4e2aSegment\uff0c\u53ef\u4ee5\u63d0\u4f9b\u76f8\u540c\u7684\u7ebf\u7a0b\u5b89\u5168,\u4f46\u662f\u6548\u7387\u63d0\u5347N\u500d\uff0c\u9ed8\u8ba4\u63d0\u534716\u500d\u3002\u5e76\u4e14\u8bfb\u64cd\u4f5c\u4e0d\u52a0\u9501\uff0c\u7531\u4e8e HashEntry \u7684value\u53d8\u91cf\u662f volatile\u7684\uff0c\u4e5f\u80fd\u4fdd\u8bc1\u8bfb\u53d6\u5230\u6700\u65b0\u7684\u503c\u3002
\n3\u3001Hashtable\u7684synchronized\u662f\u9488\u5bf9\u6574\u5f20Hash\u8868\u7684\uff0c\u5373\u6bcf\u6b21\u9501\u4f4f\u6574\u5f20\u8868\u8ba9\u7ebf\u7a0b\u72ec\u5360\uff0cConcurrentHashMap \u5141\u8bb8\u591a\u4e2a\u4fee\u6539\u64cd\u4f5c\u5e76\u53d1\u8fdb\u884c,\u5176\u5173\u952e\u5728\u4e8e\u4f7f\u7528\u4e86\u9501\u5206\u79bb\u6280\u672f
\n4\u3001\u6269\u5bb9:\u6bb5\u5185\u6269\u5bb9\uff08\u6bb5\u5185\u5143\u7d20\u8d85\u8fc7\u8be5\u6bb5\u5bf9\u5e94Entry\u6570\u7ec4\u957f\u5ea6\u768475%\u89e6\u53d1\u6269\u5bb9,\u4e0d\u4f1a\u5bf9\u6574\u4e2aMap\u8fdb\u884c\u6269\u5bb9\uff09\uff0c\u63d2\u5165\u524d\u68c0\u6d4b\u9700\u4e0d\u9700\u8981\u6269\u5bb9\uff0c\u6709\u6548\u907f\u514d\u65e0\u6548\u6269\u5bb9<\/p>\n","protected":false},"excerpt":{"rendered":"
ConcurrentHashMap\u548c Hashtable \u7684\u533a\u522b\u4e3b\u8981\u4f53\u73b0\u5728\u5b9e\u73b0\u7ebf\u7a0b\u5b89\u5168\u7684\u65b9\u5f0f\u4e0a\u4e0d\u540c \u5e95\u5c42\u6570\u636e\u7ed3 […]<\/p>\n","protected":false},"author":8,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[99],"tags":[],"class_list":["post-8687","post","type-post","status-publish","format-standard","hentry","category-javabase"],"_links":{"self":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/8687","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\/8"}],"replies":[{"embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/comments?post=8687"}],"version-history":[{"count":1,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/8687\/revisions"}],"predecessor-version":[{"id":8688,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/8687\/revisions\/8688"}],"wp:attachment":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/media?parent=8687"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/categories?post=8687"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/tags?post=8687"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}