Access object variables

[AcousticBruce]

I have created an object array using polymorphism and I would like to access those variables from my GUI class.

for instance vehicle[1].millage
the millage int variable is public in my vehicle class and car extends vehicle.

is this possible?

public class Main {
    public static void main(String[] args) {
        
        new GUI();

        Vehicle[] vehicle = new Vehicle[3];
        vehicle[0] = new Truck();
        vehicle[1] = new Car();
        vehicle[2] = new Bike();
    }
}

[ClickerMonkey]

You would need to instantiate the Vehicle array first, and pass it to the GUI class... or create a setter in the GUI class.

        Vehicle[] vehicle = new Vehicle[3];
        vehicle[0] = new Truck();
        vehicle[1] = new Car();
        vehicle[2] = new Bike();
        new GUI(vehicle);

or:

        GUI gui = new GUI(vehicle);
        Vehicle[] vehicle = new Vehicle[3];
        vehicle[0] = new Truck();
        vehicle[1] = new Car();
        vehicle[2] = new Bike();
        gui.setVehicles(vehicle);

[AcousticBruce]

        Vehicle[] vehicle = new Vehicle[3];
        vehicle[0] = new Truck();
        vehicle[1] = new Car();
        vehicle[2] = new Bike();
        new GUI(vehicle);

Create a constructor in GUI?
I do not understand how I would do this.

        GUI gui = new GUI(vehicle);
        Vehicle[] vehicle = new Vehicle[3];
        vehicle[0] = new Truck();
        vehicle[1] = new Car();
        vehicle[2] = new Bike();
        gui.setVehicles(vehicle);

It seems that only in the main static method I can access the variables, probably because I instantiated them there. But how to I instantiate the SAME object so it doesnt make a new one.

I am just not sure how to make the constructor in GUI.

[Tolls]

You don't instantiate the same object. You instantiate an object and then pass its reference around.

So the call to setVehicles passes the reference to your array to the GUI object.
Presumably the GUI object would then set an attribute equal to that reference:

public void setVehicles(Vehcile[] vehicles) {
     this.vehicles = vehicles;
}

This presumes that GUI has an attrbiute vechiles of type Vehicle[].

[AcousticBruce]

You don't instantiate the same object. You instantiate an object and then pass its reference around.

So the call to setVehicles passes the reference to your array to the GUI object.
Presumably the GUI object would then set an attribute equal to that reference:

public void setVehicles(Vehcile[] vehicles) {
     this.vehicles = vehicles;
}

This presumes that GUI has an attribute vehicles of type Vehicle[].

I have code in the main method (the static method) that manipulates the reference specifically the vehicles[]. The reference Object is made in a static method (main). When I try to reach it from a non static method / class I get an error.

I guess I am just not understanding. Can you access the variables made in a static method main like a public variable or objects?

[AcousticBruce]

Bump....

So can you call variables or references created in a static method, in my case the main method, is it possible. I do not understand the last answers.

thank you all for your help.

[Tolls]

No you can't, because they are only within the scope of that method.

However, you can pass the reference around (as I showed above).
So pass the Vechile[] reference to GUI, either through the constructor or through a setVehicle method.