>522

回答待ってるあいだに補足

Calendar　DateA = Calendar.getInstanse();
Calendar　DateB = Calendar.getInstanse();
DateA.set(int year, int month, int date);
DateB.set(int year, int month, int date);

int　yourdesire　= DateA.get(Calendar.DAY_OF_YEAR )　-　DateB.get(Calendar.DAY_OF_YEAR );