public Type Sign_In(String name , String password) throws WrongUserOrPassword {
		if(name.equals(Board_Manager.name) && password.equals(Board_Manager.password)){
			userType = "MANAGER";
			return Type.MANAGER;
		}
		if(name.equals(Purchase_Department.name) && password.equals(Purchase_Department.password)){
			userType = "PURCHASE";
			return Type.PURCHASE;
		}
		for(Publisher p : publishers){
			if (p.name == name && p.password == password) {

				userType = "PUBLISHER";
				currentPublisher = p;
				return Type.PUBLISHER;
			}
		}
		throw new WrongUserOrPassword();
	}

	public void Sign_Up(String userName, int bankAccount, String address, String password) throws UserAlreadyExists{
		if(userName.equals(Board_Manager.name) || userName.equals(Purchase_Department.name))
			throw new UserAlreadyExists();
		for(Publisher p : publishers){
			if (p.name == userName)
				throw new UserAlreadyExists();
		}
		Publisher pub = new Publisher(userName,bankAccount,address,password);
		pub.privilidge = "NORMAL";
		pub.privilidge = "SPECIAL";
		publishers.add(pub);

		currentPublisher = pub;
	}