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Java Inheritance in Java Inheritance in Java Object Equality

trying to add a parameter to a constructor but getting a message

trying to add a String parameter but keep getting an err message when instantiating the object

I keep getting this err msg

Main.java:14: error: constructor Animal in class Animal cannot be applied to given types;
        super(sound);
        ^
  required: no arguments
  found: String
  reason: actual and formal argument lists differ in length
1 error
compiler exit status 1

CODE

class Main {
    public static void main(String[] args) {
        Dog Loki = new Dog("Woof");
        Dog Thor = new Dog("Bark");
    }
}

abstract class Animal {
    String sound = "";
}

class Dog extends Animal {
    Dog(String sound) {
        super(sound);
    }
}

1 Answer

Daniel Turato
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Daniel Turato
Java Web Development Techdegree Graduate 30,124 Points

The Animal abstract class has a single field sound but doesn't have any methods or constructors, only the default Animal() constructor. So when you call super(sound) in the Dog class it won't work as you trying to call a constructor that doesn't exist. So you can do something like this:

Dog(String sound) {
  this.sound = sound
}