java_计算两个日期的时间差

import java.util.Date;
public class  {
   
    public static long dateDiff(Date d1, Date d2) throws Exception {
       long n1 = d1.getTime();
        long n2 = d2.getTime();
        long diff = Math.abs(n1 - n2);
      diff /= 3600 * 1000 * 24;
       return diff;
       }
}