摘要: int a = 1; if(a ==1 || a == 3 || a == 4 || a == 8 || a == 11){ } Map<Integer,Boolean> map = new HashMap(); map.put( 1, true); map.put( 3, true); map.p 阅读全文
posted @ 2022-01-19 17:21 滔滔江水连绵不绝 阅读(282) 评论(0) 推荐(0)
摘要: SELECT * FROM table_name WHERE ( field1,field2,field3... ) IN ( '1' , 1 ,'ONE'... ) ; 组合索引的绝妙搭配!!! 阅读全文
posted @ 2021-10-29 19:04 滔滔江水连绵不绝 阅读(311) 评论(0) 推荐(0)
摘要: //静态的计算次数;private static int start = 0; //main方法public static void main(String[] args) { System.out.println(test(9));}//测试方法public static int test(int 阅读全文
posted @ 2021-10-26 09:54 滔滔江水连绵不绝 阅读(464) 评论(0) 推荐(0)
摘要: //String类型确保小数精度BigDecimal bigDecimal = new BigDecimal("123.123");//split(String regex)放入的是正则表达,"."会全部剔除,需要"\\."String[] split = bigDecimal.toString() 阅读全文
posted @ 2021-10-26 09:34 滔滔江水连绵不绝 阅读(621) 评论(0) 推荐(0)
摘要: String content="犹如滔滔江水连绵不绝";String key="?+vM8s84mH@/";byte[] contArray = content.getBytes();int length = contArray.length;byte[] keyArray = key.getByt 阅读全文
posted @ 2021-02-03 18:58 滔滔江水连绵不绝 阅读(150) 评论(0) 推荐(0)