public boolean isValidStartDate() {
		
	    try {
	    	
	    	// create date format of selected start date
			Calendar startDate = dcStartDate.getCalendar();
			String startDateStr = startDate.get(Calendar.YEAR) + "-" 
			                  + (startDate.get(Calendar.MONTH) + 1) + "-" 
					          + startDate.get(Calendar.DAY_OF_MONTH); 
	    	
	    	DateFormat df = new SimpleDateFormat("yyyy-MM-dd");
	    	
	    	// if the date can be parsed, return true
	    	// if it can not, exception error occur, and return false
	        df.parse(startDateStr);	        
	        
	        return true;
	        
	    }catch (ParseException e) {
	        return false;
	
		}catch (NullPointerException e) {
	        return false;
	  
		}catch (Exception e) {
	        return false;
	    }
	}