{"rsdb":{"rid":"286576","subhead":"","postdate":"0","aid":"203150","fid":"76","uid":"1","topic":"1","content":"<div class=\"entry\"> \n <div class=\"copyright-area\">\n  \u539f\u6587\u51fa\u5904\uff1a \n  <a>\u5353\u5e86\u68ee<\/a>\n <\/div> \n <p>\u73b0\u5728\u662f\u665a\u4e0a11\u70b9\u4e86\uff0c\u5b66\u6821\u5c60\u732a\u9986\u7684\u81ea\u4e60\u5ba4\u56e0\u4e3a\u592a\u665a\u8981\u5173\u95ed\u4e86\u3002\u52e4\u594b\u4e14\u75b2\u60eb\u7684\u5c0f\u9c81\u73ed\u4e5f\u4ece\u5c60\u732a\u9986\u51fa\u6765\u4e86\uff0c\u6b63\u51c6\u5907\u56de\u5bbf\u820d\u6d17\u6d17\u7761\uff0c\u7531\u4e8e\u81ea\u4e60\u5ba4\u4f4d\u7f6e\u6bd4\u8f83\u504f\u50fb\u6240\u4ee5\u662f\u63a5\u6536\u4e0d\u5230\u624b\u673a\u7f51\u7edc\u4fe1\u53f7\u7684\uff0c\u56e0\u6b64\u5c0f\u9c81\u73ed\u4ece\u515c\u91cc\u638f\u51fa\u624b\u673a\u7684\u65f6\u5019\uff0c\u4fe1\u606f\u53ef\u771f\u662f\u70b8\u4e86\u5440\u3002\u5c0f\u9c81\u73ed\u5fc3\u60f3\uff0c\u5fae\u4fe1\u7fa4\u5e73\u65f6\u90fd\u6ca1\u4ec0\u4e48\u4eba\u804a\u5929\uff0c\u4eca\u665a\u80af\u5b9a\u662f\u53d1\u751f\u4e86\u4ec0\u4e48\u5927\u4e8b\u3002\u4ed4\u7ec6\u4e00\u770b\uff0c\u624d\u53d1\u73b0\u539f\u6765\u662f\u5c0f\u9c81\u73ed\u7684\u5ba4\u53cb\u8fbe\u6469\uff08\u5149\u5934\uff09\u62ff\u5230\u4e86\u963f\u91cc\u5df4\u5df4 Java \u5f00\u53d1\u5b9e\u4e60\u751f\u7684 Offer\uff0c\u6b64\u65f6\u5c0f\u9c81\u73ed\u771f\u66ff\u4ed6\u5ba4\u53cb\u611f\u5230\u9ad8\u5174\u7684\u540c\u65f6\uff0c\u5fc3\u91cc\u4e5f\u96be\u514d\u4f1a\u4ea7\u751f\u4e00\u4e1d\u4e1d\u7684\u5931\u843d\u611f\uff0c\u90a3\u662f\u56e0\u4e3a\u81ea\u5df1\u6295\u4e86\u5f88\u591a\u4efd\u7b80\u5386\uff0c\u522b\u8bf4\u62ff\u4e0d\u62ff\u5f97\u5230 Offer\uff0c\u5c31\u8fde\u7ed9\u9762\u8bd5\u9080\u7684\u516c\u53f8\u4e5f\u90fd\u5be5\u5be5\u65e0\u51e0\u3002\u5c0f\u9c81\u73ed\u8fd9\u4f1a\u53ef\u771f\u662f\u53d7\u5230\u4e86\u4e00\u4e07\u70b9<strong>\u771f\u5b9e\u66b4\u51fb\u3002<\/strong>\u4e0d\u8fc7\u5c0f\u9c81\u73ed\u8fd8\u662f\u5f88\u4e50\u89c2\u7684\uff0c\u5f88\u5feb\u8c03\u6574\u4e86\u5fc3\u6001\uff0c\u5e26\u4e0a\u8033\u673a\uff0c\u6162\u6162\u7684\u8d70\u56de\u4e86\u5bbf\u820d\uff0c\u6b63\u6253\u7b97\u51c6\u5907\u5411\u4ed6\u90a3\u795e\u5ba4\u53cb\u8fbe\u6469\u53d6\u53d6\u7ecf\u3002<\/p> \n <p>\u7247\u523b\u540e~<\/p> \n <p><strong>\u5c0f\u9c81\u73ed\uff1a<\/strong>666\uff0c\u542c\u8bf4\u4f60\u62ff\u5230\u4e86\u963f\u91cc\u7684 Offer\uff0c\u80fd\u900f\u9732\u4e00\u4e0b\u9762\u8bd5\u5185\u5bb9\u548c\u6280\u5de7\u5417\uff1f<br \/> <strong>\u8fbe\u6469\uff1a<\/strong>\u563f\u563f\u563f\uff0c\u6ca1\u95ee\u9898\u9e2d\uff0c\u53eb\u58f0\u7238\u7238\u6211\u5c31\u544a\u8bc9\u4f60\u3002<br \/> <strong>\u5c0f\u9c81\u73ed\uff1a<\/strong>\u8019\u8019\uff08\u8868\u9762\u7b11\u563b\u563b\uff0c\u5fc3\u91ccMMP\uff09<br \/> <strong>\u8fbe\u6469\uff1a<\/strong>\u5176\u5b9e\u6211\u4e5f\u4e0d\u662f\u5f88\u8bb0\u5f97\u4e86\uff08\u8bf7\u7ee7\u7eed\u88c5\uff09\uff0c\u4f46\u6211\u8fd8\u662f\u8bb0\u5f97\u90a3\u4e48\u4e00\u4e9b\u3002\u5982\u679c\u4f60\u662f\u9762\u7684 Java\uff0c\u9996\u5148\u5f53\u7136\u662fJAVA\u7684\u57fa\u7840\u77e5\u8bc6\uff1a\u6570\u636e\u7ed3\u6784\uff08Map \/ List \/ Set\u7b49\uff09\u3001<span class=\"wp_keywordlink_affiliate\"><a title=\"\u8bbe\u8ba1\u6a21\u5f0f:\u53ef\u590d\u7528\u9762\u5411\u5bf9\u8c61\u8f6f\u4ef6\u7684\u57fa\u7840\" rel=\"nofollow\" target=\"_blank\" class=\"external\">\u8bbe\u8ba1\u6a21\u5f0f<\/a><\/span>\u3001\u7b97\u6cd5\u3001\u7ebf\u7a0b\u76f8\u5173\u3001IO\/NIO\u3001\u5e8f\u5217\u5316\u7b49\u7b49\u3002\u5176\u6b21\u662f\u9ad8\u7ea7\u7279\u5f81\uff1a\u53cd\u5c04\u673a\u5236\uff0c\u5e76\u53d1\u4e0e\u9501\uff0cJVM\uff08GC\u7b56\u7565\uff0c\u7c7b\u52a0\u8f7d\u673a\u5236\uff0c\u5185\u5b58\u6a21\u578b\uff09\u7b49\u7b49\u3002<br \/> <strong>\u5c0f\u9c81\u73ed\uff1a<\/strong>\u95ee\u8fd9\u4e48\u591a\u5185\u5bb9\uff0c\u90a3\u5c82\u4e0d\u662f\u4e00\u4e2a\u4eba\u90fd\u9762\u8bd5\u5f88\u4e45\u5417\uff1f<br \/> <strong>\u8fbe\u6469\uff1a<\/strong>\u4e0d\u662f\u7684\uff0c\u9762\u8bd5\u5b98\u4e00\u822c\u90fd\u4f1a\u7528\u8fde\u73af\u70ae\u7684\u65b9\u5f0f\u63d0\u95ee\u7684\u3002<br \/> <strong>\u5c0f\u9c81\u73ed\uff1a<\/strong>\u4f60\u8bf4\u7684\u8fde\u73af\u70ae\u662f\u4ec0\u4e48\u610f\u601d\u9e2d\uff1f<br \/> <strong>\u8fbe\u6469\uff1a<\/strong>\u90a3\u6211\u4e3e\u4e2a\u4f8b\u5b50\uff1a<\/p> \n <ul> \n  <li>\u5c31\u6bd4\u5982\u95ee\u4f60&nbsp;<strong>HashMap \u662f\u4e0d\u662f\u6709\u5e8f\u7684\uff1f<\/strong>\u4f60\u56de\u7b54\u4e0d\u662f\u6709\u5e8f\u7684\u3002<\/li> \n  <li>\u90a3\u9762\u8bd5\u5b98\u5c31\u4f1a\u53ef\u80fd\u7ee7\u7eed\u95ee\u4f60\uff0c<strong>\u6709\u6ca1\u6709\u6709\u5e8f\u7684Map\u5b9e\u73b0\u7c7b\u5462\uff1f<\/strong>\u4f60\u5982\u679c\u8fd9\u4e2a\u65f6\u5019\u8bf4\u4e0d\u77e5\u9053\u7684\u8bdd\uff0c\u90a3\u8fd9\u5757\u95ee\u9898\u5c31\u5230\u6b64\u7ed3\u675f\u4e86\u3002\u5982\u679c\u4f60\u8bf4\u6709 TreeMap \u548c LinkedHashMap\u3002<\/li> \n  <li>\u90a3\u4e48\u9762\u8bd5\u5b98\u63a5\u4e0b\u6765\u5c31\u53ef\u80fd\u4f1a\u95ee\u4f60\uff0c<strong>TreeMap \u548c LinkedHashMap \u662f\u5982\u4f55\u4fdd\u8bc1\u5b83\u7684\u987a\u5e8f\u7684\uff1f<\/strong>\u5982\u679c\u4f60\u56de\u7b54\u4e0d\u4e0a\u6765\uff0c\u90a3\u4e48\u5230\u6b64\u4e3a\u6b62\u3002\u5982\u679c\u4f60\u8bf4 TreeMap \u662f\u901a\u8fc7\u5b9e\u73b0 SortMap \u63a5\u53e3\uff0c\u80fd\u591f\u628a\u5b83\u4fdd\u5b58\u7684\u952e\u503c\u5bf9\u6839\u636e key \u6392\u5e8f\uff0c\u57fa\u4e8e\u7ea2\u9ed1\u6811\uff0c\u4ece\u800c\u4fdd\u8bc1 TreeMap \u4e2d\u6240\u6709\u952e\u503c\u5bf9\u5904\u4e8e\u6709\u5e8f\u72b6\u6001\u3002LinkedHashMap \u5219\u662f\u901a\u8fc7\u63d2\u5165\u6392\u5e8f\uff08\u5c31\u662f\u4f60 put \u7684\u65f6\u5019\u7684\u987a\u5e8f\u662f\u4ec0\u4e48\uff0c\u53d6\u51fa\u6765\u7684\u65f6\u5019\u5c31\u662f\u4ec0\u4e48\u6837\u5b50\uff09\u548c\u8bbf\u95ee\u6392\u5e8f\uff08\u6539\u53d8\u6392\u5e8f\u628a\u8bbf\u95ee\u8fc7\u7684\u653e\u5230\u5e95\u90e8\uff09\u8ba9\u952e\u503c\u6709\u5e8f\u3002<\/li> \n  <li>\u90a3\u4e48\u9762\u8bd5\u5b98\u8fd8\u4f1a\u7ee7\u7eed\u95ee\u4f60\uff0c<strong>\u4f60\u89c9\u5f97\u5b83\u4eec\u4e24\u4e2a\u54ea\u4e2a\u7684\u6709\u5e8f\u5b9e\u73b0\u6bd4\u8f83\u597d\uff1f<\/strong>\u5982\u679c\u4f60\u4f9d\u7136\u53ef\u4ee5\u56de\u7b54\u7684\u8bdd\uff0c\u90a3\u4e48\u9762\u8bd5\u5b98\u4f1a\u7ee7\u7eed\u95ee\u4f60\uff0c<strong>\u4f60\u89c9\u5f97\u8fd8\u6709\u6ca1\u6709\u6bd4\u5b83\u66f4\u597d\u6216\u8005\u66f4\u9ad8\u6548\u7684\u5b9e\u73b0\u65b9\u5f0f\uff1f<\/strong><\/li> \n <\/ul> \n <p>\u65e0\u7a77\u65e0\u5c3d\u6df1\u5165\uff0c\u76f4\u5230\u4f60\u56de\u7b54\u4e0d\u51fa\u6765\u6216\u8005\u9762\u8bd5\u5b98\u8ba4\u4e3a\u95ee\u9898\u5230\u5e95\u4e86\u3002<\/p> \n <p>\u5c0f\u9c81\u73ed\u634f\u4e86\u4e00\u628a\u6c57\uff0c\u6211\u53bb\u2026\u2026\u8fd9\u662f\u9b54\u9b3c\u5427\uff0c\u90a3\u6211\u4eec\u6765\u8bd5\u8bd5\u5457\uff08\u56e0\u4e3a\u5c0f\u9c81\u73ed\u521a\u521a\u5728\u81ea\u4e60\u5ba4\u624d\u770b\u4e86\u8fd9\u7ae0\u7684\u77e5\u8bc6\uff0c\u60f3\u8d81\u673a\u88c5\u4e00\u6ce2\u903c\uff0c\u6bd5\u7adf\u521a\u521a\u53eb\u4e86\u58f0\u7238\u7238~~\uff09<\/p> \n <p>\u4e8e\u662f\u8fbe\u6469 and \u5c0f\u9c81\u73ed\u5c31\u5f00\u59cb\u4e86\u5bf9\u51b3\uff1a<\/p> \n <h3>1\u3001\u4e3a\u4ec0\u4e48\u7528HashMap\uff1f<\/h3> \n <ul> \n  <li>HashMap \u662f\u4e00\u4e2a\u6563\u5217\u6876\uff08\u6570\u7ec4\u548c\u94fe\u8868\uff09\uff0c\u5b83\u5b58\u50a8\u7684\u5185\u5bb9\u662f\u952e\u503c\u5bf9 key-value \u6620\u5c04<\/li> \n  <li>HashMap \u91c7\u7528\u4e86\u6570\u7ec4\u548c\u94fe\u8868\u7684\u6570\u636e\u7ed3\u6784\uff0c\u80fd\u5728\u67e5\u8be2\u548c\u4fee\u6539\u65b9\u4fbf\u7ee7\u627f\u4e86\u6570\u7ec4\u7684\u7ebf\u6027\u67e5\u627e\u548c\u94fe\u8868\u7684\u5bfb\u5740\u4fee\u6539<\/li> \n  <li>HashMap \u662f\u975e synchronized\uff0c\u6240\u4ee5 HashMap \u5f88\u5feb<\/li> \n  <li>HashMap \u53ef\u4ee5\u63a5\u53d7 null \u952e\u548c\u503c\uff0c\u800c Hashtable \u5219\u4e0d\u80fd\uff08\u539f\u56e0\u5c31\u662f equlas() \u65b9\u6cd5\u9700\u8981\u5bf9\u8c61\uff0c\u56e0\u4e3a HashMap \u662f\u540e\u51fa\u7684 API \u7ecf\u8fc7\u5904\u7406\u624d\u53ef\u4ee5\uff09<\/li> \n <\/ul> \n <h3>2\u3001HashMap \u7684\u5de5\u4f5c\u539f\u7406\u662f\u4ec0\u4e48\uff1f<\/h3> \n <h4>HashMap \u662f\u57fa\u4e8e hashing \u7684\u539f\u7406<\/h4> \n <p>\u6211\u4eec\u4f7f\u7528 put(key, value) \u5b58\u50a8\u5bf9\u8c61\u5230 HashMap \u4e2d\uff0c\u4f7f\u7528 get(key) \u4ece HashMap \u4e2d\u83b7\u53d6\u5bf9\u8c61\u3002\u5f53\u6211\u4eec\u7ed9 put() \u65b9\u6cd5\u4f20\u9012\u952e\u548c\u503c\u65f6\uff0c\u6211\u4eec\u5148\u5bf9\u952e\u8c03\u7528 hashCode() \u65b9\u6cd5\uff0c\u8ba1\u7b97\u5e76\u8fd4\u56de\u7684 hashCode \u662f\u7528\u4e8e\u627e\u5230 Map \u6570\u7ec4\u7684 bucket \u4f4d\u7f6e\u6765\u50a8\u5b58 Node \u5bf9\u8c61\u3002<\/p> \n <p>\u8fd9\u91cc\u5173\u952e\u70b9\u5728\u4e8e\u6307\u51fa\uff0cHashMap \u662f\u5728 bucket \u4e2d\u50a8\u5b58\u952e\u5bf9\u8c61\u548c\u503c\u5bf9\u8c61\uff0c\u4f5c\u4e3aMap.Node \u3002<\/p> \n <p><a rel=\"attachment wp-att-31279\"><img class=\"aligncenter size-full wp-image-31279\" title=\"1294463-20181119000932124-498988644\" src=\"http:\/\/incdn1.b0.upaiyun.com\/2019\/01\/eeae778630faa2239fad75b90bd6123c.png\" alt=\"\" \/><\/a><\/p> \n <h4>\u4ee5\u4e0b\u662f HashMap \u521d\u59cb\u5316<\/h4> \n <p><strong><\/strong>\u7b80\u5316\u7684\u6a21\u62df\u6570\u636e\u7ed3\u6784\uff1a<\/p> \n <pre class=\"brush: java; gutter: true\">Node[] table = new Node[16]; \/\/ \u6563\u5217\u6876\u521d\u59cb\u5316\uff0ctable\r\nclass Node {\r\n    hash; \/\/hash\u503c\r\n    key; \/\/\u952e\r\n    value; \/\/\u503c\r\n    node next; \/\/\u7528\u4e8e\u6307\u5411\u94fe\u8868\u7684\u4e0b\u4e00\u5c42\uff08\u4ea7\u751f\u51b2\u7a81\uff0c\u7528\u62c9\u94fe\u6cd5\uff09\r\n}<\/pre> \n <h4>\u4ee5\u4e0b\u662f\u5177\u4f53\u7684 put \u8fc7\u7a0b\uff08JDK1.8\uff09<\/h4> \n <ol> \n  <li>\u5bf9 Key \u6c42 Hash \u503c\uff0c\u7136\u540e\u518d\u8ba1\u7b97\u4e0b\u6807<\/li> \n  <li>\u5982\u679c\u6ca1\u6709\u78b0\u649e\uff0c\u76f4\u63a5\u653e\u5165\u6876\u4e2d\uff08\u78b0\u649e\u7684\u610f\u601d\u662f\u8ba1\u7b97\u5f97\u5230\u7684 Hash \u503c\u76f8\u540c\uff0c\u9700\u8981\u653e\u5230\u540c\u4e00\u4e2a bucket \u4e2d\uff09<\/li> \n  <li>\u5982\u679c\u78b0\u649e\u4e86\uff0c\u4ee5\u94fe\u8868\u7684\u65b9\u5f0f\u94fe\u63a5\u5230\u540e\u9762<\/li> \n  <li>\u5982\u679c\u94fe\u8868\u957f\u5ea6\u8d85\u8fc7\u9600\u503c\uff08TREEIFY THRESHOLD==8\uff09\uff0c\u5c31\u628a\u94fe\u8868\u8f6c\u6210\u7ea2\u9ed1\u6811\uff0c\u94fe\u8868\u957f\u5ea6\u4f4e\u4e8e6\uff0c\u5c31\u628a\u7ea2\u9ed1\u6811\u8f6c\u56de\u94fe\u8868<\/li> \n  <li>\u5982\u679c\u8282\u70b9\u5df2\u7ecf\u5b58\u5728\u5c31\u66ff\u6362\u65e7\u503c<\/li> \n  <li>\u5982\u679c\u6876\u6ee1\u4e86\uff08\u5bb9\u91cf16*\u52a0\u8f7d\u56e0\u5b500.75\uff09\uff0c\u5c31\u9700\u8981 resize\uff08\u6269\u5bb92\u500d\u540e\u91cd\u6392\uff09<\/li> \n <\/ol> \n <h4>\u4ee5\u4e0b\u662f\u5177\u4f53 get \u8fc7\u7a0b<\/h4> \n <p><strong>\u8003\u8651\u7279\u6b8a\u60c5\u51b5\uff1a<\/strong>\u5982\u679c\u4e24\u4e2a\u952e\u7684 hashcode \u76f8\u540c\uff0c\u4f60\u5982\u4f55\u83b7\u53d6\u503c\u5bf9\u8c61\uff1f<\/p> \n <p>\u5f53\u6211\u4eec\u8c03\u7528 get() \u65b9\u6cd5\uff0cHashMap \u4f1a\u4f7f\u7528\u952e\u5bf9\u8c61\u7684 hashcode \u627e\u5230 bucket \u4f4d\u7f6e\uff0c\u627e\u5230 bucket \u4f4d\u7f6e\u4e4b\u540e\uff0c\u4f1a\u8c03\u7528 keys.equals() \u65b9\u6cd5\u53bb\u627e\u5230\u94fe\u8868\u4e2d\u6b63\u786e\u7684\u8282\u70b9\uff0c\u6700\u7ec8\u627e\u5230\u8981\u627e\u7684\u503c\u5bf9\u8c61\u3002<\/p> \n <p><a rel=\"attachment wp-att-31280\"><img class=\"aligncenter size-full wp-image-31280\" title=\"1294463-20181119002141457-19724606\" src=\"http:\/\/incdn1.b0.upaiyun.com\/2019\/01\/c3b34af2d13802399d5e61bb5b8cb87b.png\" alt=\"\" \/><\/a><\/p> \n <h3>3\u3001\u6709\u4ec0\u4e48\u65b9\u6cd5\u53ef\u4ee5\u51cf\u5c11\u78b0\u649e\uff1f<\/h3> \n <h4>\u6270\u52a8\u51fd\u6570\u53ef\u4ee5\u51cf\u5c11\u78b0\u649e<\/h4> \n <p>\u539f\u7406\u662f\u5982\u679c\u4e24\u4e2a\u4e0d\u76f8\u7b49\u7684\u5bf9\u8c61\u8fd4\u56de\u4e0d\u540c\u7684 hashcode \u7684\u8bdd\uff0c\u90a3\u4e48\u78b0\u649e\u7684\u51e0\u7387\u5c31\u4f1a\u5c0f\u4e9b\u3002\u8fd9\u5c31\u610f\u5473\u7740\u5b58\u94fe\u8868\u7ed3\u6784\u51cf\u5c0f\uff0c\u8fd9\u6837\u53d6\u503c\u7684\u8bdd\u5c31\u4e0d\u4f1a\u9891\u7e41\u8c03\u7528 equal \u65b9\u6cd5\uff0c\u4ece\u800c\u63d0\u9ad8 HashMap \u7684\u6027\u80fd\uff08\u6270\u52a8\u5373 Hash \u65b9\u6cd5\u5185\u90e8\u7684\u7b97\u6cd5\u5b9e\u73b0\uff0c\u76ee\u7684\u662f\u8ba9\u4e0d\u540c\u5bf9\u8c61\u8fd4\u56de\u4e0d\u540chashcode\uff09\u3002<\/p> \n <h4>\u4f7f\u7528\u4e0d\u53ef\u53d8\u7684\u3001\u58f0\u660e\u4f5c final \u5bf9\u8c61\uff0c\u5e76\u4e14\u91c7\u7528\u5408\u9002\u7684 equals() \u548c hashCode() \u65b9\u6cd5\uff0c\u5c06\u4f1a\u51cf\u5c11\u78b0\u649e\u7684\u53d1\u751f<\/h4> \n <p>\u4e0d\u53ef\u53d8\u6027\u4f7f\u5f97\u80fd\u591f\u7f13\u5b58\u4e0d\u540c\u952e\u7684 hashcode\uff0c\u8fd9\u5c06\u63d0\u9ad8\u6574\u4e2a\u83b7\u53d6\u5bf9\u8c61\u7684\u901f\u5ea6\uff0c\u4f7f\u7528 String\u3001Integer \u8fd9\u6837\u7684 wrapper \u7c7b\u4f5c\u4e3a\u952e\u662f\u975e\u5e38\u597d\u7684\u9009\u62e9\u3002<\/p> \n <h4>\u4e3a\u4ec0\u4e48 String\u3001Integer \u8fd9\u6837\u7684 wrapper \u7c7b\u9002\u5408\u4f5c\u4e3a\u952e\uff1f<\/h4> \n <p>\u56e0\u4e3a String \u662f final\uff0c\u800c\u4e14\u5df2\u7ecf\u91cd\u5199\u4e86 equals() \u548c hashCode() \u65b9\u6cd5\u4e86\u3002\u4e0d\u53ef\u53d8\u6027\u662f\u5fc5\u8981\u7684\uff0c\u56e0\u4e3a\u4e3a\u4e86\u8981\u8ba1\u7b97 hashCode()\uff0c\u5c31\u8981\u9632\u6b62\u952e\u503c\u6539\u53d8\uff0c\u5982\u679c\u952e\u503c\u5728\u653e\u5165\u65f6\u548c\u83b7\u53d6\u65f6\u8fd4\u56de\u4e0d\u540c\u7684 hashcode \u7684\u8bdd\uff0c\u90a3\u4e48\u5c31\u4e0d\u80fd\u4ece HashMap \u4e2d\u627e\u5230\u4f60\u60f3\u8981\u7684\u5bf9\u8c61\u3002<\/p> \n <h3>4\u3001HashMap \u4e2d hash \u51fd\u6570\u600e\u4e48\u662f\u5b9e\u73b0\u7684?<\/h3> \n <p>\u6211\u4eec\u53ef\u4ee5\u770b\u5230\uff0c\u5728 hashmap \u4e2d\u8981\u627e\u5230\u67d0\u4e2a\u5143\u7d20\uff0c\u9700\u8981\u6839\u636e key \u7684 hash \u503c\u6765\u6c42\u5f97\u5bf9\u5e94\u6570\u7ec4\u4e2d\u7684\u4f4d\u7f6e\u3002\u5982\u4f55\u8ba1\u7b97\u8fd9\u4e2a\u4f4d\u7f6e\u5c31\u662f hash \u7b97\u6cd5\u3002<\/p> \n <p>\u524d\u9762\u8bf4\u8fc7\uff0chashmap \u7684\u6570\u636e\u7ed3\u6784\u662f\u6570\u7ec4\u548c\u94fe\u8868\u7684\u7ed3\u5408\uff0c\u6240\u4ee5\u6211\u4eec\u5f53\u7136\u5e0c\u671b\u8fd9\u4e2a hashmap \u91cc\u9762\u7684\u5143\u7d20\u4f4d\u7f6e\u5c3d\u91cf\u7684\u5206\u5e03\u5747\u5300\u4e9b\uff0c\u5c3d\u91cf\u4f7f\u5f97\u6bcf\u4e2a\u4f4d\u7f6e\u4e0a\u7684\u5143\u7d20\u6570\u91cf\u53ea\u6709\u4e00\u4e2a\u3002\u90a3\u4e48\u5f53\u6211\u4eec\u7528 hash \u7b97\u6cd5\u6c42\u5f97\u8fd9\u4e2a\u4f4d\u7f6e\u7684\u65f6\u5019\uff0c\u9a6c\u4e0a\u5c31\u53ef\u4ee5\u77e5\u9053\u5bf9\u5e94\u4f4d\u7f6e\u7684\u5143\u7d20\u5c31\u662f\u6211\u4eec\u8981\u7684\uff0c\u800c\u4e0d\u7528\u518d\u53bb\u904d\u5386\u94fe\u8868\u3002 \u6240\u4ee5\uff0c\u6211\u4eec\u9996\u5148\u60f3\u5230\u7684\u5c31\u662f\u628a hashcode \u5bf9\u6570\u7ec4\u957f\u5ea6\u53d6\u6a21\u8fd0\u7b97\u3002\u8fd9\u6837\u4e00\u6765\uff0c\u5143\u7d20\u7684\u5206\u5e03\u76f8\u5bf9\u6765\u8bf4\u662f\u6bd4\u8f83\u5747\u5300\u7684\u3002<\/p> \n <p>\u4f46\u662f\u201c\u6a21\u201d\u8fd0\u7b97\u7684\u6d88\u8017\u8fd8\u662f\u6bd4\u8f83\u5927\u7684\uff0c\u80fd\u4e0d\u80fd\u627e\u4e00\u79cd\u66f4\u5feb\u901f\u3001\u6d88\u8017\u66f4\u5c0f\u7684\u65b9\u5f0f\uff1f\u6211\u4eec\u6765\u770b\u770b JDK1.8 \u6e90\u7801\u662f\u600e\u4e48\u505a\u7684\uff08\u88ab\u697c\u4e3b\u4fee\u9970\u4e86\u4e00\u4e0b\uff09<\/p> \n <pre class=\"brush: java; gutter: true\">static final int hash(Object key) {\r\n    if (key == null){\r\n        return 0;\r\n    }\r\n    int h","orderid":"0","title":"HashMap\uff1f\u9762\u8bd5\uff1f\u6211\u662f\u8c01\uff1f\u6211\u5728\u54ea(\u4e00)","smalltitle":"","mid":"0","fname":"JAVA","special_id":"0","bak_id":"0","info":"0","hits":"570","pages":"3","comments":"0","posttime":"2019-01-10 00:08:54","list":"1547050134","username":"admin","author":"","copyfrom":"","copyfromurl":"","titlecolor":"","fonttype":"0","titleicon":"0","picurl":"http:\/\/incdn1.b0.upaiyun.com\/2019\/01\/eeae778630faa2239fad75b90bd6123c.png","ispic":"1","yz":"1","yzer":"","yztime":"0","levels":"0","levelstime":"0","keywords":"<A HREF='https:\/\/www.cppentry.com\/do\/search.php?type=keyword&keyword=HashMap' target=_blank>HashMap<\/A> <A HREF='https:\/\/www.cppentry.com\/do\/search.php?type=keyword&keyword=%C3%E6%CA%D4' target=_blank>\u9762\u8bd5<\/A>","jumpurl":"","iframeurl":"","style":"","template":"a:3:{s:4:\"head\";s:0:\"\";s:4:\"foot\";s:0:\"\";s:8:\"bencandy\";s:0:\"\";}","target":"0","ip":"47.106.78.186","lastfid":"0","money":"0","buyuser":"","passwd":"","allowdown":"","allowview":"","editer":"","edittime":"0","begintime":"0","endtime":"0","description":"HashMap\uff1f\u9762\u8bd5\uff1f\u6211\u662f\u8c01\uff1f\u6211\u5728\u54ea","lastview":"1713883576","digg_num":"0","digg_time":"0","forbidcomment":"0","ifvote":"0","heart":"","htmlname":"","city_id":"0"},"page":"1"}