获取前一天

/**
	 * 获取前一天
	 * 
	 * @param date
	 * @return
	 */
	public static Date getBeforeDay(Date date) {
		Calendar calendar = Calendar.getInstance();
		calendar.setTime(date);
		calendar.add(Calendar.DAY_OF_MONTH, -1);
		date = calendar.getTime();
		return date;
	}