{"id":1134,"date":"2022-10-24T22:49:20","date_gmt":"2022-10-24T14:49:20","guid":{"rendered":"https:\/\/qaqaq.top\/?p=1134"},"modified":"2022-11-27T12:39:49","modified_gmt":"2022-11-27T04:39:49","slug":"%e5%b8%b8%e7%94%a8%e7%b1%bb-system%e3%80%81math%e3%80%81biginteger%e3%80%81bigdecimal%e7%9a%84%e4%bd%bf%e7%94%a8","status":"publish","type":"post","link":"https:\/\/qaqaq.top\/?p=1134","title":{"rendered":"\u5e38\u7528\u7c7b-System\u3001Math\u3001BigInteger\u3001BigDecimal\u7684\u4f7f\u7528"},"content":{"rendered":"\n<pre class=\"wp-block-code\"><code>package top.qaqaq.java.P494;\r\n\r\nimport org.junit.jupiter.api.Test;\r\n\r\nimport java.math.BigDecimal;\r\nimport java.math.BigInteger;\r\n\r\n\/**\r\n * \u5176\u4ed6\u5e38\u7528\u7c7b\u7684\u4f7f\u7528\r\n * 1.System\r\n * 2.Math\r\n * 3.BigInteger \u548c BigDecimal\r\n *\r\n * @author RichieZhang\r\n * @create 2022-10-23 \u4e0b\u5348 10:27\r\n *\/\r\npublic class OtherClassTest {\r\n\r\n    @Test\r\n    public void test1() {\r\n        String javaVersion = System.getProperty(\"java.version\");\r\n        System.out.println(\"java\u7684version:\" + javaVersion);\r\n\r\n        String javaHome = System.getProperty(\"java.home\");\r\n        System.out.println(\"java\u7684home:\" + javaHome);\r\n\r\n        String osName = System.getProperty(\"os.name\");\r\n        System.out.println(\"os\u7684name:\" + osName);\r\n\r\n        String osVersion = System.getProperty(\"os.version\");\r\n        System.out.println(\"os\u7684version:\" + osVersion);\r\n\r\n        String userName = System.getProperty(\"user.name\");\r\n        System.out.println(\"user\u7684name:\" + userName);\r\n\r\n        String userHome = System.getProperty(\"user.home\");\r\n        System.out.println(\"user\u7684home:\" + userHome);\r\n\r\n        String userDir = System.getProperty(\"user.dir\");\r\n        System.out.println(\"user\u7684dir:\" + userDir);\r\n    }\r\n\r\n    @Test\r\n    public void test2() {\r\n        BigInteger bi = new BigInteger(\"124332411231231321114411414142141241414142141421231123\");\r\n        BigDecimal bd = new BigDecimal(\"12435.351\");\r\n        BigDecimal bd2 = new BigDecimal(\"11\");\r\n        System.out.println(bi);\r\n        System.out.println(bd.divide(bd2));\r\n        System.out.println(bd.divide(bd2, BigDecimal.ROUND_HALF_UP));\r\n        System.out.println(bd.divide(bd2, 25, BigDecimal.ROUND_HALF_UP));\r\n\r\n        \/\/\u9879\u76ee\u4e2d\u6d89\u53ca\u5230\u8ba1\u7b97\u91d1\u989d\u7684, \u90e8\u5206\u4ee3\u7801\u5982\u4e0b, \u7f16\u8bd1\u5668\u63d0\u793aROUND_HALF_UP is deprecated. \u4e0d\u63a8\u8350\u4f7f\u7528.\r\n        \/\/ \u4ecejava9\u5c31\u4e0d\u63a8\u8350\u4f7f\u7528\u4e86.\u4fee\u6539\u65b9\u6848:\u5c06BigDecimal.ROUND_HALF_UP\u6539\u4e3a:RoundingMode.HALF_UP\r\n    }\r\n}\r\n<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[8],"tags":[46],"class_list":["post-1134","post","type-post","status-publish","format-standard","hentry","category-java-code","tag-java"],"_links":{"self":[{"href":"https:\/\/qaqaq.top\/index.php?rest_route=\/wp\/v2\/posts\/1134"}],"collection":[{"href":"https:\/\/qaqaq.top\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/qaqaq.top\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/qaqaq.top\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/qaqaq.top\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1134"}],"version-history":[{"count":1,"href":"https:\/\/qaqaq.top\/index.php?rest_route=\/wp\/v2\/posts\/1134\/revisions"}],"predecessor-version":[{"id":1135,"href":"https:\/\/qaqaq.top\/index.php?rest_route=\/wp\/v2\/posts\/1134\/revisions\/1135"}],"wp:attachment":[{"href":"https:\/\/qaqaq.top\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1134"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/qaqaq.top\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1134"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/qaqaq.top\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1134"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}