What's the best way to pass an object as a paremeter into a method in Java?

I would like to pass an object called user created from the Player class into my playerSetup method. However, when I pass user into the method, and try to call user.setName(), Java gives an error and recommends I do ((Player) user).setName(input.nextLine()) instead. This works but it seems a bit messy, especially if I’m going to be doing this in other methods as well.

Is there a better way to go about this or am I stuck with this solution?

Main.java

public class Main {
    public static void main(String arg[]) {
        Scanner input = new Scanner(System.in);
        Player user = new Player();
        playerSetup(input, user);
        
        System.out.println(user.getName());
    }

    private static void playerSetup(Scanner input, Object user) {
        System.out.println("Hello, please enter your name: ");  
/*
        user.setName(input.nextLine()); -- I would like for it to look like this,
        however it won't work and my IDE reccomends I do it like the line below.
*/
        ((Player) user).setName(input.nextLine()); // This seems messy having to reference the Player class every time
        System.out.println("Hello " + ((Player) user).getName());
    }
}

Player.java

public class Player {
private String name;
    public void setName(String name) {
        this.name = name;
    }
    public String getName() {
        return this.name;
    }
}

>Solution :

To avoid the need to cast user to Player in your playerSetup method, you can change the method signature to explicitly accept a Player object instead of a generic Object. This way, you can directly call Player methods without casting.

Here’s how you can modify your Main class:

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        Player user = new Player();
        playerSetup(input, user);
        
        System.out.println(user.getName());
    }

    private static void playerSetup(Scanner input, Player user) {
        System.out.println("Hello, please enter your name: ");
        user.setName(input.nextLine());
        System.out.println("Hello " + user.getName());
    }
}

By changing the parameter type of playerSetup from Object to Player, you can now call setName and getName directly on the user object without needing to cast it. This makes your code cleaner and more readable.

Here’s the complete Player class for reference:

public class Player {
    private String name;

    public void setName(String name) {
        this.name = name;
    }

    public String getName() {
        return this.name;
    }
}