{"id":40,"date":"2012-12-07T05:08:41","date_gmt":"2012-12-07T05:08:41","guid":{"rendered":"http:\/\/www.dongcb.com\/?p=40"},"modified":"2012-12-07T05:08:41","modified_gmt":"2012-12-07T05:08:41","slug":"java%e5%af%b9%e6%95%b0%e5%ad%97%e5%8f%96%e6%95%b4","status":"publish","type":"post","link":"https:\/\/www.dongchangbin.net.cn\/?p=40","title":{"rendered":"Java\u5bf9\u6570\u5b57\u53d6\u6574"},"content":{"rendered":"<p>\u73b0\u5b9e\u64cd\u4f5c\u4e2d\u6709\u5f88\u591a\u9700\u8981\u53d6\u6574\u7684\u5730\u65b9\uff0c\u53d6\u5c0f\u6570\u4f4d\u6570\u7684\u5730\u65b9\uff0c\u6bd4\u5982\u4e00\u4e2a\u73ed\u6709n\u4e2a\u4eba\uff0c\u60f3\u89814\u4eba\u4e00\u7ec4\u5206\u7ec4\uff0c\u90a3\u4e48\u7ec4\u6570\u662f\u591a\u5c11\uff1fn\u9664\u4ee54\u5411\u4e0a\u53d6\u6574\uff1b\u6bd4\u5982\u5185\u90e8\u8ba1\u7b97\u65f6\u9700\u8981\u5c0f\u6570\u70b9\u540e\u5c3d\u53ef\u80fd\u591a\u7684\u4f4d\u6570\uff0c\u4f46\u662f\u8d22\u52a1\u53ea\u9700\u8981\u4e24\u4f4d\u5c0f\u6570\uff0c\u9700\u8981\u622a\u53d6\uff1b\u6bd4\u5982\u5185\u90e8\u8ba1\u7b97\u7684\u65f6\u5019\u4e3a\u4e86\u7cbe\u786e\uff0c\u8ba1\u7b97\u8fc7\u7a0b\u4e2d\u6240\u7528\u6570\u5b57\u5c0f\u6570\u4f4d\u6570\u81f3\u5c11\u8981\u6bd4\u663e\u793a\u4f4d\u6570\u591a\uff0c\u90a3\u4e48\u663e\u793a\u548c\u5b58\u50a8\u7684\u65f6\u5019\u90fd\u9700\u8981\u5bf9\u6570\u5b57\u8fdb\u884c\u622a\u53d6\u3002<\/p>\n<p>\u8fd9\u4e9b\u53d6\u6574\u548c\u622a\u53d6\u7684\u8fc7\u7a0b\u53ef\u80fd\u53d1\u751f\u5728\u9875\u9762\u7684\u811a\u672c\u4e2d\u6216\u8005java\u7a0b\u5e8f\u4e2d\u6216\u8005sql\u8bed\u53e5\u4e2d\u3002\u8fd9\u6bb5\u65f6\u95f4\u5c31\u78b0\u5230\u4e00\u4e2a\u95ee\u9898\uff0c\u5c31\u7c7b\u4f3c\u4e8e\u4e0a\u9762\u63d0\u5230\u7684\u73ed\u7ea7\u5b66\u751f\u5206\u7ec4\u7684\u95ee\u9898\u3002\u6570\u5b57\u7684\u8fd0\u7b97\u81ea\u7136\u4e0d\u662f\u95ee\u9898\uff0c\u60f3\u8981\u901a\u8fc7\u81ea\u5df1\u5199\u7684\u4ee3\u7801\u83b7\u5f97\u5e94\u8be5\u6709\u7684\u7ec4\u6570\u4e5f\u6ca1\u95ee\u9898\uff0c\u4f46\u662fjava\u5df2\u7ecf\u63d0\u4f9b\u4e86\u73b0\u6210\u7684\u65b9\u6cd5\uff0c\u81ea\u5df1\u5c31\u4e0d\u8981\u518d\u505a\u4e00\u4e9b\u65e0\u7528\u529f\u4e86\u3002<\/p>\n<p>java\u91cc\u53d6\u6574\u7684\u51fd\u6570\u6709\u4ee5\u4e0b\u4e09\u4e2a\uff1a<\/p>\n<p>Math.floor();Math.ceil()\u548cBigDecimal\u3002\u867d\u7136\u90fd\u662f\u53d6\u6574\u51fd\u6570\uff0c\u4f46\u662f\u65b9\u6cd5\u7684\u610f\u4e49\u548c\u8fd4\u56de\u503c\u5374\u662f\u4e0d\u4e00\u6837\u7684\u3002<\/p>\n<p>\u7528\u6cd5\u5206\u522b\u5982\u4e0b\uff1a<\/p>\n<p>Math.floor()<br \/>\n\u901a\u8fc7\u8be5\u51fd\u6570\u8ba1\u7b97\u540e\u7684\u8fd4\u56de\u503c\u662f\u820d\u53bb\u5c0f\u6570\u70b9\u540e\u7684\u6570\u503c<br \/>\n\u5982\uff1aMath.floor(3.2)\u8fd4\u56de3<br \/>\nMath.floor(3.9)\u8fd4\u56de3<br \/>\nMath.floor(3.0)\u8fd4\u56de3<\/p>\n<p>Math.ceil()<br \/>\nceil\u51fd\u6570\u53ea\u8981\u5c0f\u6570\u70b9\u975e0\uff0c\u5c06\u8fd4\u56de\u6574\u6570\u90e8\u5206+1<br \/>\n\u5982\uff1aMath.ceil(3.2)\u8fd4\u56de4<br \/>\nMath.ceil(3.9)\u8fd4\u56de4<br \/>\nMath.ceil(3.0)\u8fd4\u56de3<\/p>\n<p>BigDecimal\u56db\u820d\u4e94\u5165<br \/>\n\u4f20\u7edf\u7684\u56db\u820d\u4e94\u5165\uff0c\u5728Math\u7c7b\u4e2d\u5e76\u6ca1\u6709\u76f4\u63a5\u63d0\u4f9b\uff0c\u5fc5\u987b\u4f7f\u7528Java.math.BigDecimal\u7c7b\u6765\u5b9e\u73b0<br \/>\nnew BigDecimal(&#8220;2.0&#8221;).setScale(0, BigDecimal.ROUND_HALF_UP)\u8fd4\u56de2<br \/>\nnew BigDecimal(&#8220;2.4&#8221;).setScale(0, BigDecimal.ROUND_HALF_UP)\u8fd4\u56de2<br \/>\nnew BigDecimal(&#8220;2.5&#8221;).setScale(0, BigDecimal.ROUND_HALF_UP)\u8fd4\u56de3<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u73b0\u5b9e\u64cd\u4f5c\u4e2d\u6709\u5f88\u591a\u9700\u8981\u53d6\u6574\u7684\u5730\u65b9\uff0c\u53d6\u5c0f\u6570\u4f4d\u6570\u7684\u5730\u65b9\uff0c\u6bd4\u5982\u4e00\u4e2a\u73ed\u6709n\u4e2a\u4eba\uff0c\u60f3\u89814\u4eba\u4e00\u7ec4\u5206\u7ec4\uff0c\u90a3\u4e48\u7ec4\u6570\u662f\u591a\u5c11\uff1fn\u9664\u4ee5 [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-40","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v24.1 - 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