public boolean setFinishTimeOfTask(Task task){
		boolean isFound = false;
		for(Task tmp : tasks){
			boolean result = task.equal(tmp);
			if(result){
				isFound = true;
				tmp.setFinishTime(task.getFinishTime());
				break;
			}
		}
		if(!isFound){
			for(Task tmp : tasks){
				if(tmp.getPriority() == -1){
					tmp.setFinishTime(task.getFinishTime());
				}
			}
			return true;
		}
		return false;
	}