Access object inside abstract class

Asked Apr 14 '16 at 17:18

Active Apr 14 '16 at 17:22

Viewed 72 times

I have an abstract class as follows:

public abstract class ServerClass extends AsyncServer {

    private Validator serverValidator;

    public ServerClass(Validator val) {

        serverContext = ctx;
        serverValidator = val;
    }

    public start() {

        result(serverValidator.start("foo"));
    }

    abstract void result(String r);
};

Then, I call this method as follows:

ServerClass server = new ServerClass(validator) {

    @Override
    void result(String r) {

        useString(r);
    }
};

But for some reason the String r (returned from result()) is null. Is there something wrong in this code?

edited Apr 14 '16 at 17:22

Evan Porter

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asked Apr 14 '16 at 17:18

Rafael Maia

1

See this http://stackoverflow.com/questions/40480/is-java-pass-by-reference-or-pass-by-value – AdamSkywalker Apr 14 '16 at 17:20
How does your validator look? – Ferrybig Apr 14 '16 at 17:21
_String r (returned from result())_ this method returns nothing, I don't understand – Nicolas Filotto Apr 14 '16 at 17:24
i think you are not passing string argument at all to method result(). have look at it. – Prabhakar Apr 14 '16 at 17:28
but your result() method doesn't return anything. – Raman Shrivastava Apr 14 '16 at 17:37
You cannot modify the passed-in String. Strings in Java (and many languages) are immutable. You can [read a lot](http://stackoverflow.com/questions/1552301/immutability-of-strings-in-java) about this concept online. – DavidS Apr 14 '16 at 17:41
the method: validator.start("foo") works fine outside ServerClass class. – Rafael Maia Apr 14 '16 at 18:15

Access object inside abstract class

0 Answers0