组成和清单

Question

我想在组成列表中添加一个名称。我在这里做错了什么？另外，如果我想添加的不仅仅是一个名称，是否可以在Customer类中添加另一个字段呢？ （即使它不是字符串？）

public class Main {
private static Customer cus;    
private static Firstclass fc = new Firstclass(cus);    

public static void main(String[] args) {

        fc.addFirstClass("John");
        System.out.println("The list of FirstClass passengers is " + fc.getFirstClass());
    }

public class Firstclass {

    private Customer customer;
    private ArrayList<Customer> firstClass;

    public Firstclass(Customer customer) {
        this.firstClass = new ArrayList<>();
        this.customer = customer;
    }

    public void addFirstClass(String name) {
        firstClass.add(new Customer(name));
        System.out.println(name + " was added to firstclass.");
    }

    public ArrayList<Customer> getFirstClass() {
        return firstClass;
    }
}


public class Customer {

    private String name;

    public String getName() {
        return name;
    }

    public Customer(String name) {
        this.name = name;
    }
}