Access superclass static variable in subclass

Question

I have a superclass Test with a static variable a and I've also created a subclass Test1 from which I am able to access superclass static variable.

Is this a valid way to do so? Any explanation is highly appreciated.

public class Test {

    public static String a = "";

    Test() {
        a += "testadd";
    }
}

public class Test1 extends Test {

    public Test1() {
        a += "test1add";
    }

    public static void main(String args[]){
        Test1 test1 = new Test1();
        System.out.println(a);
    }
}

@AlexErohin, static variable belongs to a class and in my case it belongs to super class and I can access that variable in sub class also. How can it be? any valid reasons. My Initial thought was, only I can access super class instance variable and methods in sub class. — VSK, Oct 04 '15 at 04:04
Please, take a look at this thread: http://stackoverflow.com/a/9898144/4745608 — Aleksandr Erokhin, Oct 04 '15 at 14:06

score 3 · Answer 1 · edited Oct 03 '15 at 23:02

You can access it using the subclass object.superClassStaticField or SuperClassName.superClassStaticField. Latter is the static way to access a static variable.

For example:

public class SuperClassStaticVariable {
    public static void main(String[] args) {
        B b = new B();
        b.a = 2; // works but compiler warning that it should be accessed as static way
        A.a = 2; // ok 
    }
}

class A {   
    static int a;
}
class B extends A {}

score 1 · Answer 2 · edited Oct 03 '15 at 22:43

Static variables are class variables, you can access them using classname.variablename.

public class Test {

    public static String a = "";

    Test() {
        a += "testadd";
    }
}

public class Test1 extends Test {

    public Test1() {
        Test.a += "test1add";
    }

    public static void main(String args[]) {
        Test1 test1 = new Test1();
        System.out.println(a);
    }
}

Access superclass static variable in subclass

2 Answers2