// 每一个1号删除上个月的数据	public String calculateDay() {		String dd = "";		DateFormat dateFormat = new SimpleDateFormat("yyyy-MM");		String nowdayTime = dateFormat.format(new Date());		try {			dateFormat.parse(nowdayTime);		} catch (ParseException e) {			e.printStackTrace();		}		String[] timStrings = nowdayTime.split("-");		String nowYear = timStrings[0];		String nowMath = timStrings[1];		if (nowMath.equals("01")) {			int lastYear = Integer.parseInt(nowYear) - 1;			dd = lastYear + "";		} else {			int lastMath = Integer.parseInt(nowMath) - 1;			String lastMath_ = String.format("%02d", lastMath);			String s = nowYear + "-" + lastMath_;			dd = s;		}		System.err.println(dd);		return dd;	}