java integear 转 string 补0
参考：
java中int转成String位数不足前面补零
https://blog.csdn.net/u013991521/article/details/55819876
Android 开发数字不足位数前面补0
https://blog.csdn.net/qq_32556691/article/details/106567017
java整形格式化补0_Java Android 开发数字不足位数前面补0
https://blog.csdn.net/weixin_39884373/article/details/114594757?spm=1001.2101.3001.6650.1&utm_medium=distribute.pc_relevant.none-task-blog-2%7Edefault%7ECTRLIST%7Edefault-1.pc_relevant_paycolumn_v2&depth_1-utm_source=distribute.pc_relevant.none-task-blog-2%7Edefault%7ECTRLIST%7Edefault-1.pc_relevant_paycolumn_v2&utm_relevant_index=2
Android 数字转字符串、保留两位小数、千分位、补 0、百分比
http://cftea.com/c/2017/03/6843.asp