Overiding Methods

All classes are descendents of the Object class. Object contains the toString method, which returns a String object containing the name of the object's class and its hash code.

class Super {
    int aNumber;
    public String toString() {
        String result = super.toString() + " aNumber:" + aNumber;
        return result;
    }
    public void setANumber(int i) {
        aNumber = i;
    }
}

class Sub extends Super {
    float aNumber;
    public String toString() {
        String result = super.toString() + " aNumber:" + aNumber;
        return result;
    }
    public void setANumber(int i) { //overide Super's
        aNumber = (float)i / 2;
        super.aNumber = i;  //call overrided method in Super
    }
    public static void main(String[] args) {
        Sub sub = new Sub();
        sub.setANumber(5);
        System.out.println(sub.toString());
    }
}