Java如何使用另一个类的实例访问方法

我正在尝试写一个小游戏来帮助我提高Java技能。我有一个名为“ Zombie”和“ Player”的类，并按如下方式创建了这些类的实例：

Zombie zombie = new Zombie(50, "Infected Zombie", "Slash");
Player defaultPlayer = new Player(100, "Default Player");

接下来，我要求用户输入播放器的攻击方式：

System.out.println("Which attack style would you like to use?");
        defaultPlayer.printAttackStyles();
        int option = scanner.nextInt();
        scanner.nextLine();
        switch(option) {
            case 0:
                System.out.println("You backed out of the fight.");
                break;
            case 1:
                System.out.println("Punching...");
                defaultPlayer.attack(1);
                break;
            case 2:
                System.out.println("Kicking...");
                defaultPlayer.attack(2);
                break;
            case 3:
                System.out.println("Headbutting...");
                defaultPlayer.attack(3);
                break;
            case 4:
                System.out.println("Tackling...");
                defaultPlayer.attack(4);
                break;
            default:
                System.out.println("Not a valid attack style");
        }

在我的“玩家”类中，我有一种称为Attack的方法，该方法会根据攻击方式造成一定程度的损害：

public int attack(int attackStyle) {
        int damage = 0;

        switch(attackStyle) {
            case 0:
                damage = 0;
                break;
            case 1:
                damage = random.nextInt(20) + 1;
                zombie.removeHealth(damage);
                break;
            case 2:
                damage = random.nextInt(25) + 1;
                zombie.removeHealth(damage);
                break;
            case 3:
                damage = random.nextInt(30) + 1;
                zombie.removeHealth(damage);
                this.health -= random.nextInt(5) + 1;
                break;
            case 4:
                damage = random.nextInt(45) + 1;
                zombie.removeHealth(damage);
                this.health -= random.nextInt(10) + 1;
                break;
        }

        return damage;
    }

在每种攻击方式下，我都有一行代码指出

zombie.removeHealth(damage);

由于该实例仅在Main类中声明，因此如何访问该实例才能访问zombie类中的方法removeHealth（）？抱歉，这个问题很简单，但我无法解决。