Diferenca em dias dado 2 datas

Date d1 = new Date(System.currentTimeMillis()); //substituir pelas suas datas

Date d2 = new Date(System.currentTimeMillis() - 277200000);//substituir pelas suas datas

Calendar calendar1 = Calendar.getInstance();

Calendar calendar2 = Calendar.getInstance();

calendar1.setTime(d1);

calendar2.setTime(d2);

int years = calendar1.get(Calendar.YEAR) - calendar2.get(Calendar.YEAR);

int months = calendar1.get(Calendar.MONTH) - calendar2.get(Calendar.MONTH);

int days = calendar1.get(Calendar.DAY_OF_MONTH) - calendar2.get(Calendar.DAY_OF_MONTH);

int hours = calendar1.get(Calendar.HOUR_OF_DAY) - calendar2.get(Calendar.HOUR_OF_DAY);

if (years > 0 && (months < 0 || (months == 0 && days < 0))) {

years -= 1;

}

System.out.println("Anos : " + years + " Meses " + months + " Dias " + days + " Horas " + hours);