時間計算工具

工作中用到了很多的有關時間計算的工具方法,特此留念

 /**  
     * 計算兩個日期之間相差的天數  
     * @param smdate 較小的時間 
     * @param bdate  較大的時間 
     * @return 相差天數 
     * @throws ParseException  
     */    
    public static int daysBetween(Date smdate,Date bdate){    
        SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM-dd");  
        try {
			smdate=sdf.parse(sdf.format(smdate));
		} catch (ParseException e) {
			logger.error(e.getMessage(),e.fillInStackTrace());
		}  
        try {
			bdate=sdf.parse(sdf.format(bdate));
		} catch (ParseException e) {
			logger.error(e.getMessage(),e.fillInStackTrace());
		}  
        Calendar cal = Calendar.getInstance();    
        cal.setTime(smdate);    
        long time1 = cal.getTimeInMillis();                 
        cal.setTime(bdate);    
        long time2 = cal.getTimeInMillis();         
        long between_days=(time2-time1)/(1000*3600*24);
        if(between_days==0)//如果小於一天按一天計算
        	return 1;            
       return Integer.parseInt(String.valueOf(between_days));           
    }    
      
	/** 
	*字符串的日期格式的計算 
	*/ 
    public static int daysBetween(String smdate,String bdate){  
        SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM-dd");  
        Calendar cal = Calendar.getInstance();    
        try {
			cal.setTime(sdf.parse(smdate));
		} catch (ParseException e) {
			logger.error(e.getMessage(),e.fillInStackTrace());
		}    
        long time1 = cal.getTimeInMillis();                 
        try {
			cal.setTime(sdf.parse(bdate));
		} catch (ParseException e) {
			logger.error(e.getMessage(),e.fillInStackTrace());
		}    
        long time2 = cal.getTimeInMillis();         
        long between_days=(time2-time1)/(1000*3600*24);  
            
       return Integer.parseInt(String.valueOf(between_days));     
    }
    
    /**
     * 根據指定日 劃分時間段
     * @param start
     * @param end
     * @param settlement
     * @return
     */
    public static List<Date> divideDateByMonth(Date start,Date end,Integer settlement){
    	List<Date> dates=new ArrayList<Date>();
    	Calendar calendar = Calendar.getInstance();
    	Date datePoint=(Date)start.clone();
    	dates.add(datePoint);
    	
    	if(settlement!=null){
    	
    		calendar.setTime(datePoint);
    		calendar.set(Calendar.DATE, settlement);
    		if(datePoint.compareTo(calendar.getTime())>0){
    			   calendar.add(Calendar.MONTH, 1); 			
    		}   		
    		datePoint=calendar.getTime();
    		dates.add(datePoint);
    	}   	
    	
    	
    	while(true){    		
    		calendar.setTime(datePoint);
    		calendar.add(Calendar.MONTH, 1);
    		
    		if(calendar.getTime().before(end)){
    			datePoint=(Date) calendar.getTime();
    			dates.add(datePoint);    			    			
    		}else{
    			break;
    		}
    	}
    	dates.add(end);
    	return dates;    	
    }
    
    /**
     * 獲得從開始日期到結束日期的 月數 和天數
     * @param start
     * @param end
     * @return
     */
    public static Integer[] getMonthAndDayNum(Date start,Date end){
		
    	Date datePoint=(Date) start.clone();
		
		int mNumber=0;//月份數
		int restDays=0;
		while (datePoint.before(end)) {
			Calendar calendar = Calendar.getInstance();
			calendar.setTime(datePoint);
			calendar.add(Calendar.MONTH, 1);
			datePoint=calendar.getTime();
			if(datePoint.before(end))
				mNumber++;
			
		}
		
		Calendar calendar = Calendar.getInstance();
		calendar.setTime(datePoint);
		calendar.add(Calendar.MONTH, -1);
		datePoint=calendar.getTime();
		restDays=daysBetween(datePoint, end);
		
		Integer[] result= new Integer[]{mNumber,restDays};
		
		return result;		
    	
    }
    /**
     * 月份相等
     * @param d1
     * @param d2
     * @return
     */
    public static boolean monthEqual(Date d1,Date d2){
		Calendar calendar1=Calendar.getInstance();
		Calendar calendar2=Calendar.getInstance();
		calendar1.setTime(d1);
		calendar2.setTime(d2);
		int m1=calendar1.get(Calendar.MONTH);
    	int m2=calendar2.get(Calendar.MONTH);
    	
    	return m1==m2;
    	
    }
    
    /**
     * 月份加
     * @param date
     * @param amount
     * @return
     */
    public static Date monthAdd(Date date,int amount){
    	Calendar calendar=Calendar.getInstance();
    	calendar.setTime(date);
    	calendar.add(Calendar.MONTH, amount);
    	return calendar.getTime();
    }
    /**
     * 日期加
     * @param date
     * @param amount
     * @return
     */
    public static Date dayAdd(Date date,int amount) {
    	Calendar calendar=Calendar.getInstance();
    	calendar.setTime(date);
    	calendar.add(Calendar.DATE, amount);
    	return calendar.getTime();
	}