使用Java保存到数据库时更改Excel日期数据的日期格式

I have my codes written to save my user's data in an excel file into MySQL database. While I run it, everything works fine except the date is wrong. In the excel file, the date format is dd.MM.yyyy, whereas the date format in MySQL is yyyy-MM-dd. What should I do in my code to convert the date format while saving it into database?I have my codes written to save my user's data