public abstract class Tool {

    private double durability;

    public double getDurability() {
        return durability;
    }

    public void setDurability(double durability) {
        this.durability = durability;
    }
}

public class Axe extends Tool {

    public void chop() {
        //chop some wood
    }
}

Tool tool = new Axe();

((Axe)tool).chop();

if (tool instanceof Axe) {
    ((Axe)tool).chop();
}

abstract class Tool {

    private double durability;

    public double getDurability() {
        return durability;
    }

    public void setDurability(double durability) {
        this.durability = durability;
    }

    public void work(){

    }
}




class Axe extends Tool {

        @Override
        public void work() {
            this.chop();
        }

        public void chop() {
            //chop some wood
        }
    }

Axe axe = (Axe) tool;
axe.chop();

if (tool instanceof Axe){
  Axe axe = (Axe) tool;
  axe.chop();
}