java判断时间先后顺序 java判断时间差

 如果只是简单的使用毫秒相减，会有误差，所以先统一时分秒

/**
 * 通过时间秒毫秒数判断两个时间的间隔
 * @param date1
 * @param date2
 * @return
 */
private  int getDayCount(Date date1,Date date2){
	date1 = CalToDate(date1);
	date2 = CalToDate(date2);
	int days = (int) ((date2.getTime() - date1.getTime()) / (1000*3600*24));
	return days;
}
private  Date CalToDate(Date date1){
	Calendar date = Calendar.getInstance();
	date.setTime(date1);
	int year = date.get(Calendar.YEAR);
	int mouth = date.get(Calendar.MONTH);
	int day = date.get(Calendar.DATE);
	Calendar data2 = Calendar.getInstance();
	data2.set(year,mouth,day,23,59,59);
	return data2.getTime();
}