怎樣求2個日期間隔的工作日數?解決

還有很多要完善的地方，還有簡單的實現沒？希望各位幫我提提意見。。。。。

/*步驟： 類CountDaysByDate
 * 1、中間天數處理
 * 2、開始時間處理
 * 3、結束時間處理
*/
    private static int[] val = new int[] { 1, 7 };// 默認休息日爲 六，日

	private static double WORK_DAY_COUNT = 7.5;	//定義一天的有幾個小時

	//設置上下班時間、中午休息時間
	private static int AM_START_HOUR = 9; 
	private static int AM_START_MINUTE = 0;
	private static int AM_END_HOUR = 12; 
	private static int AM_END_MINUTE = 0; 
	private static int PM_START_HOUR = 13; 
	private static int PM_START_MINUTE = 0; 
	private static int PM_END_HOUR = 17; 
	private static int PM_END_MINUTE = 30; 
	private static double NOON_REST = 1; 

	/**
	 * 計算2個日期相差天數（排除休息日）
	 * @param beginDateStr
	 * @param endDateStr
	 * @return
	 * 步驟：
	 * 1、中間天數處理
	 * 2、開始時間處理
	 * 3、結束時間處理
	 */
	@SuppressWarnings("deprecation")
	public static double getDaysByDate(String beginDateStr,String endDateStr){
		double result = 0;
		double restTime = NOON_REST;//中午休息時間
		Calendar beginCalendar = getCalendar(beginDateStr);
		Calendar endCalendar = getCalendar(endDateStr);
		/**1、中間天數處理**/
		int days = getMargin(beginDateStr, endDateStr);
		/**2、開始時間處理**/
		if(days>0){//不是同一天
			//開始天上午工作開始-結束時間
			Calendar amStartWork1 = setHourAndMinute(getCalendar(beginDateStr),AM_START_HOUR,AM_START_MINUTE);
			Calendar amEndWork1 = setHourAndMinute(getCalendar(beginDateStr),AM_END_HOUR,AM_END_MINUTE);
			//開始天下午工作開始-結束時間
			//Calendar pmStartWork1 = setHourAndMinute(getCalendar(beginDateStr),PM_START_HOUR,PM_START_MINUTE);
			Calendar pmEndWork1 = setHourAndMinute(getCalendar(beginDateStr),PM_END_HOUR,PM_END_MINUTE);
			beginCalendar = setOverTime(beginDateStr);
			//計算開始天還有多少分鐘
			int bvalue = 0;
			if(beginCalendar.compareTo(amStartWork1)>=0 && beginCalendar.compareTo(pmEndWork1)<=0){//beginCalendar<=pmEndWork1
				bvalue = ((int)(pmEndWork1.getTimeInMillis() - beginCalendar.getTimeInMillis()))/(60*1000) ;
				if(beginCalendar.compareTo(amEndWork1)<0){//beginCalendar<amEndWork1
					bvalue -= (int)(restTime*60);
				}
			}
			/**3、結束時間處理**/
			//末尾天上午工作開始-結束時間
			Calendar amStartWork2 = setHourAndMinute(getCalendar(endDateStr),AM_START_HOUR,AM_START_MINUTE);
			Calendar amEndWork2 = setHourAndMinute(getCalendar(endDateStr),AM_END_HOUR,AM_END_MINUTE);
			//末尾天下午工作開始-結束時間
			//Calendar pmStartWork2 = setHourAndMinute(getCalendar(endDateStr),PM_START_HOUR,PM_START_MINUTE);
			Calendar pmEndWork2 = setHourAndMinute(getCalendar(endDateStr),PM_END_HOUR,PM_END_MINUTE);
			endCalendar = setOverTime(endDateStr);
			//計算末尾天還有多少分鐘
			int evalue = 0;
			if(endCalendar.compareTo(amStartWork2)>=0 && endCalendar.compareTo(pmEndWork2)<=0){//endCalendar<=pmEndWork2
				evalue = ((int)(pmEndWork2.getTimeInMillis() - endCalendar.getTimeInMillis()))/(60*1000) ;
				if(endCalendar.compareTo(amEndWork2)<0){//endCalendar<amEndWork2
					evalue -= (int)(restTime*60);
				}
			}
			double total = (bvalue - evalue)/((double)WORK_DAY_COUNT*60);
			result = days + total;
			result = ((int)(result*100))/(double)100;
		}else{//同一天
			int bvalue = 0;
			if(endCalendar.compareTo(beginCalendar)>0 ){//endCalendar>beginCalendar
				//上午工作開始-結束時間
				//Calendar amStartWork1 = setHourAndMinute(getCalendar(beginDateStr),AM_START_HOUR,AM_START_MINUTE);
				Calendar amEndWork1 = setHourAndMinute(getCalendar(beginDateStr),AM_END_HOUR,AM_END_MINUTE);
				//下午工作開始-結束時間
				Calendar pmStartWork1 = setHourAndMinute(getCalendar(beginDateStr),PM_START_HOUR,PM_START_MINUTE);
				//Calendar pmEndWork1 = setHourAndMinute(getCalendar(beginDateStr),PM_END_HOUR,PM_END_MINUTE);
				beginCalendar = setOverTime(beginDateStr);
				endCalendar = setOverTime(endDateStr);
				/**2中情況：特殊的->《9:00~17:00》; 普通的->《9:00~12:00》《13:00~17:00》;**/
				bvalue = ((int)(endCalendar.getTimeInMillis() - beginCalendar.getTimeInMillis()))/(60*1000) ;
				if(beginCalendar.compareTo(amEndWork1)<0 && endCalendar.compareTo(pmStartWork1)>0){//beginCalendar<amEndWork1
					bvalue -= (int)(restTime*60);
				}
				double total = (bvalue)/((double)WORK_DAY_COUNT*60);
				result = ((int)(total*100))/(double)100;
			}else{
				result = 0;
			}
		}
		return result;
	}

	/**
	 * 設置時間在工作時間範圍內
	 * @param base
	 * @param amSw
	 * @param amEw
	 * @param pmSw
	 * @param pmEw
	 * @return
	 */
	public static Calendar setOverTime(String base){
		Calendar cal = getCalendar(base);
		//上午工作開始-結束時間
		Calendar amSw = setHourAndMinute(getCalendar(base),AM_START_HOUR,AM_START_MINUTE);
		Calendar amEw = setHourAndMinute(getCalendar(base),AM_END_HOUR,AM_END_MINUTE);
		//下午工作開始-結束時間
		Calendar pmSw = setHourAndMinute(getCalendar(base),PM_START_HOUR,PM_START_MINUTE);
		Calendar pmEw = setHourAndMinute(getCalendar(base),PM_END_HOUR,PM_END_MINUTE);
		if(cal.before(amSw)){//如果操作日期爲上午工作開始時間之前，指定一個默認值
			cal = setHourAndMinute(cal,AM_START_HOUR,AM_START_MINUTE);
		}else if(cal.after(amEw) && cal.before(pmSw)){//如果操作日期爲12：00~13：00，指定一個默認值
			cal = setHourAndMinute(cal,PM_START_HOUR,PM_START_MINUTE);
		}else if(cal.after(pmEw) ){//如果操作日期爲17:30後			cal = setHourAndMinute(cal,PM_END_HOUR,PM_END_MINUTE);
		}else if(cal.compareTo(amEw)==0 || cal.compareTo(pmSw)==0){
			cal = setHourAndMinute(cal,PM_START_HOUR,PM_START_MINUTE);//如果操作日期爲12：00/13：00
		}
		return cal;
	}

	/**
	 * 取得2個日期之間的休息日數目
	 * @param sDate
	 * @param eDate
	 * @return
	 */
	@SuppressWarnings("static-access")
	public static int getRestDays(String bDateStr,String eDateStr){
		int days = 0;
		Calendar bDate = getCalendar(bDateStr);
		Calendar eDate = getCalendar(eDateStr);
		while(eDate.after(bDate)){
			//判斷是否有休息日
			for (int i = 0; i < val.length; i++) {
				if (bDate.get(bDate.DAY_OF_WEEK) == val[i]) {
					days ++;
				}
			}
			bDate.add(bDate.DATE,1);
		}
		return days;
	}

	/**
	 * 計算2個日期之間的天數（排除休息日），例如：2009-04-07 15:00:00 ~ 2009-04-09 15:00:00之間只有2009-04-08一天，則返回1,此處可加入排除節假日的方法。。。。。。
	 * @param bDateStr
	 * @param eDateStr
	 * @return
	 */
	@SuppressWarnings("static-access")
	public static int getMargin(String bDateStr, String eDateStr) {
		int margin;
		int resDays = 0;
		try {
			Calendar bDate = getCalendar(bDateStr);
			Calendar eDate = getCalendar(eDateStr);
			long l = eDate.getTimeInMillis() - bDate.getTimeInMillis();
			margin = (int) (l /(24 * 60 * 60 * 1000));
			while(eDate.after(bDate)){//判斷是否有休息日
				for (int i = 0; i < val.length; i++) {
					if (bDate.get(bDate.DAY_OF_WEEK) == val[i]) {
						resDays ++;
					}
				}
				bDate.add(bDate.DATE,1);
			}
			return (int)(margin-resDays);
		} catch (Exception e) {
			return 0;
		}
	}

	/**
	 * 根據日期字符串得到它的Calendar對象
	 * 
	 * @param date
	 * @param df
	 * @return
	 */
	public static Calendar getCalendar(String date) {
		Calendar da = Calendar.getInstance();
		SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm");// 定義時間格式
		SimpleDateFormat df1 = new SimpleDateFormat("yyyy-MM-dd");// 定義時間格式
		try {

			try{
				da.setTime(df.parse(date));
			}catch(Exception ex){
				da.setTime(df1.parse(date));
			}			
		} catch (ParseException e) {
			e.printStackTrace();
		}
		return da;
	}

	/**
	 * Calendar時分設置輔助方法
	 * @param cal
	 * @param hour
	 * @param minute
	 * @return
	 */
	public static Calendar setHourAndMinute(Calendar cal,int hour,int minute){
		cal.set(Calendar.HOUR_OF_DAY,hour);
		cal.set(Calendar.MINUTE,minute);
		return cal;
	}

public static void main(String[] args) {
		String str1 = "2009-04-07 12:00:00";
		String str2 = "2009-04-08 13:45:00";
		double days = CountDaysByDate.getDaysByDate(str1, str2);
		System.out.println(str1+"-》"+str2+"=="+days);
}