使用SimpleDateFormat的日期差异

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

public class DateDifferenceExample {
    public static void main(String[] args) {
        String startDateString = "2022-01-01";
        String endDateString = "2022-01-10";

        SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd");

        try {
            Date startDate = format.parse(startDateString);
            Date endDate = format.parse(endDateString);

            long difference = Math.abs(endDate.getTime() - startDate.getTime());
            long differenceInDays = difference / (24 * 60 * 60 * 1000);

            System.out.println("日期差异：" + differenceInDays + "天");
        } catch (ParseException e) {
            e.printStackTrace();
        }
    }
}