用java语言写个订单号类：AF+年(09)+月+日+“0000流水号”如：AF0912110001

Question

如题所述

Answer 1

import java.text.SimpleDateFormat;
import java.util.Date;

public class Order {

private static final String AF = "AF";
private static int serial = 1;

public String generateOrder(){
StringBuilder sb = new StringBuilder();
sb.append(serial++);

while(sb.length() < 4){
sb.insert(0, "0");
}

sb.insert(0, new SimpleDateFormat("yyMMdd").format(new Date()));
sb.insert(0, AF);

return sb.toString();
}

public static void main(String args[]){
System.out.println(new Order().generateOrder());
System.out.println(new Order().generateOrder());
}

}
---------testing
AF1202240001
AF1202240002

Answer 2

前面获取系统时间，后面用自增（先判断在自增）

Answer 3

字符串拼接就能实现把