abstract extended and hiding variable??

[Ace_Of_John]

im trying to fugure out how to make a variable of an abstract class available for the subclass but not available externaly.
// The abstract

Code:

public abstract class Animal
{
    protected String name;//<---This is the variable

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

    public void setName(String nm)
    {
	name=nm;
    }
    
    public abstract void speak();
}

//The subclass

Code:

public class Bird extends Animal
{

    public Bird(String nm)
    {
	name = nm;
    }

    public void speak()
    {
	System.out.println("Tweet tweet chirp");
    }
}

//The main class, i dont want this to work because i would prefer a setName() method

Code:

public static void main(String[] args)
    {
    Bird abird=new Bird("");
    abird.name="Dodo";//<======Stop this
    abird.setName("Dodo")//<====Leaving only this
    }

this is just a practice and is not part of an important project. if anyone can help i would be very greatfull. thankyou

[hardwired]

Code:

private String name;

[CaptainMorgan]

Quote:

Originally Posted by hardwired

Code:

private String name;

I saw this hardwired, but then name would not be available within class Bird. To access it from Bird, then when calling the constructor instead of

Code:

name = nm;

it would have to be

Code:

setName(nm);

as in the Main method, technically not making the variable available to the subclass. I don't think that's what is desired - I believe s/he wants to use the constructor as is. It's possible in a non-abstract class while using a protected variable.. but I'm not sure how to do it abstract-wise.

[hardwired]

Try this

Code:

public class ClassTest
{
    public static void main(String[] args)
    {
        Bird abird=new Bird("");
        System.out.println(abird);
//        abird.name="Dodo";  // compile error: name has private access in Animal
        abird.setName("Dodo");
        System.out.println(abird);
    }
}

abstract class Animal
{
    private String name;

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

    public void setName(String nm)
    {
        name = nm;
    }
    
    public abstract void speak();

    public String toString()
    {
        return getClass().getName() + "[name: " + name + "]";
    }
}

class Bird extends Animal
{
    public Bird(String nm)
    {
        super.setName(nm);
    }

    public void speak()
    {
        System.out.println("Tweet tweet chirp");
    }
}

Another way you could do it is like this

Code:

abstract class Animal
{
    private String name;

    Animal(String name)
    {
        this.name = name;
    }
    ...

class Bird extends Animal
{
    public Bird(String nm)
    {
        super(nm);
    }

[spoon!]

the original post should work; the variable is protected; that does exactly what you want

[CaptainMorgan]

Quote:

Originally Posted by spoon!

the original post should work; the variable is protected; that does exactly what you want

Yes, it works - as was implied in the original post. But the OP is asking for a customization on the abstract class's variable so it can't be accessed externally(as in main()). It appears you are misreading the OP's post.. but I'll leave that for her or him to decide officially since its his/her thread.