java - 将用户输入与 getter 进行比较

Question

我正在尝试比较用户输入“用户名”以获取买家类“Buyer.getUser”中的方法，并比较“密码”以获取买家类“Buyer.getPass”中的方法
它一直要求我在买家类中将用户名和密码设置为静态，但是即使输入了正确的输入，这仍然总是表明登录不成功。

用户类别

switch (credentials) {
        case 1 : {
            System.out.println("Buyer");
            System.out.println("Enter Username: ");
            username = S.next();
            System.out.println("Enter Password: ");
            password = S.next();

                            if ((username.equals(Buyer.getUser())) && (password.equals(Buyer.getPass()))){
                                System.out.println("Login Successful");
                            }else{ 
                                System.out.println("Login unsucessful");
            break;
        }
                    }

买家类别

public class Buyer {

private String username;
private String password; 


public Buyer (String username, String password){
    this.username = username;
    this.password = password;
}

public String getUser(){
    return username;
}

public String getPass(){
    return password;
}

用户类别

public static void buyerCredentials() {
    ArrayList<Buyer> buyer = new ArrayList<Buyer>();

    buyer.add(new Buyer("user1", "pass123"));
    buyer.add(new Buyer("user2", "pass321"));

    for (int i = 0; i < buyer.size(); i++){
        System.out.println(buyer.get(i));
    }
}

提前致谢!

Answer 1

实际上，您没有创建 Buyer 类的对象，而是调用变量作为静态引用，而不是对象，因此用户名和密码总是为 null。

Buyer buyer = new Buyer();
buyer.getUser();
buyer.getPass();