Java时间

//获取当前日期的最小值
	public static Date getStartTime() {
		Calendar todayStart = Calendar.getInstance();
		todayStart.set(Calendar.HOUR_OF_DAY, 0);
		todayStart.set(Calendar.MINUTE, 0);
		todayStart.set(Calendar.SECOND, 0);
		todayStart.set(Calendar.MILLISECOND, 0);
		return todayStart.getTime();
	}
	//获取当前日期的最大值
	public static Date getEndTime() {
		Calendar todayEnd = Calendar.getInstance();
		todayEnd.set(Calendar.HOUR_OF_DAY, 23);
		todayEnd.set(Calendar.MINUTE, 59);
		todayEnd.set(Calendar.SECOND, 59);
		todayEnd.set(Calendar.MILLISECOND, 999);
		return todayEnd.getTime();
	}
	//获取当前日期的前一天的最小值
	public static Date getYesterdayStartTime(){
		Calendar yesterdayStart= Calendar.getInstance();
		yesterdayStart.add(Calendar.DATE, -1);
		yesterdayStart.set(Calendar.HOUR_OF_DAY, 0);
		yesterdayStart.set(Calendar.MINUTE, 0);
		yesterdayStart.set(Calendar.SECOND, 0);
		yesterdayStart.set(Calendar.MILLISECOND, 0);
		return yesterdayStart.getTime();
	}
	//获取当前日期的前一天的最大值
	public static Date getYesterdayEndTime(){
		Calendar yesterdayEnd = Calendar.getInstance();
		yesterdayEnd.add(Calendar.DATE, -1);
		yesterdayEnd.set(Calendar.HOUR_OF_DAY, 23);
		yesterdayEnd.set(Calendar.MINUTE, 59);
		yesterdayEnd.set(Calendar.SECOND, 59);
		yesterdayEnd.set(Calendar.MILLISECOND, 999);
		return yesterdayEnd.getTime();
	}
	//获取当前日期的前二天的最小值
	public static Date getTheDayBeforeYesterdayStartTime(){
		Calendar yesterdayStart= Calendar.getInstance();
		yesterdayStart.add(Calendar.DATE, -2);
		yesterdayStart.set(Calendar.HOUR_OF_DAY, 0);
		yesterdayStart.set(Calendar.MINUTE, 0);
		yesterdayStart.set(Calendar.SECOND, 0);
		yesterdayStart.set(Calendar.MILLISECOND, 0);
		return yesterdayStart.getTime();
	}
	//获取当前日期的前一天的最大值
	public static Date getTheDayBeforeYesterdayEndTime(){
		Calendar yesterdayEnd = Calendar.getInstance();
		yesterdayEnd.add(Calendar.DATE, -2);
		yesterdayEnd.set(Calendar.HOUR_OF_DAY, 23);
		yesterdayEnd.set(Calendar.MINUTE, 59);
		yesterdayEnd.set(Calendar.SECOND, 59);
		yesterdayEnd.set(Calendar.MILLISECOND, 999);
		return yesterdayEnd.getTime();
	}
	
	public static Date getCurrYearFirst(){
		Calendar currCal=Calendar.getInstance();
		int currentYear = currCal.get(Calendar.YEAR);
		return getYearFirst(currentYear);
	}

	
	public static Date getCurrYearLast(){
		Calendar currCal=Calendar.getInstance();
		int currentYear = currCal.get(Calendar.YEAR);
		return getYearLast(currentYear);
	}
	
	public static Date getYearFirst(int year){
		Calendar calendar = Calendar.getInstance();
		calendar.clear();
		calendar.set(Calendar.YEAR, year);
		calendar.set(Calendar.HOUR_OF_DAY, 0);
		calendar.set(Calendar.MINUTE, 0);
		calendar.set(Calendar.SECOND, 0);
		calendar.set(Calendar.MILLISECOND, 0);
		Date currYearFirst = calendar.getTime();
		return currYearFirst;
	}

	
	public static Date getYearLast(int year){
		Calendar calendar = Calendar.getInstance();
		calendar.clear();
		calendar.set(Calendar.YEAR, year);
		calendar.roll(Calendar.DAY_OF_YEAR, -1);
		calendar.set(Calendar.HOUR_OF_DAY, 23);
		calendar.set(Calendar.MINUTE, 59);
		calendar.set(Calendar.SECOND, 59);
		calendar.set(Calendar.MILLISECOND, 999);
		Date currYearLast = calendar.getTime();

		return currYearLast;
	}
	
	public static Date getMonthFirstDay(){
		Calendar calendar = Calendar.getInstance();
		calendar.set(Calendar.DAY_OF_MONTH,1);
		calendar.add(Calendar.MONTH,0);
		calendar.set(Calendar.HOUR_OF_DAY, 0);
		calendar.set(Calendar.MINUTE, 0);
		calendar.set(Calendar.SECOND, 0);
		calendar.set(Calendar.MILLISECOND, 0);
		return calendar.getTime();
	}
	
	public static Date getMonthLastDay(){
		Calendar calendar = Calendar.getInstance();
		calendar.set(Calendar.DAY_OF_MONTH, calendar.getActualMaximum(Calendar.DAY_OF_MONTH));
		calendar.set(Calendar.HOUR_OF_DAY, 23);
		calendar.set(Calendar.MINUTE, 59);
		calendar.set(Calendar.SECOND, 59);
		calendar.set(Calendar.MILLISECOND, 999);
		return calendar.getTime();
	}