Question

HI there

I tried to run this code as an example given by my teacher, but when I copied and tried to run, then it ask to create BagInterface and ArrayBag class. Do i have to do something more previously in order to run this code. Can anyone help me her please?

import java.util.Arrays;

public class BagTraceExample {

   public static void main(String[] args) {
       BagInterface<String> animalBag = new ArrayBag();
      
          
       System.out.println(animalBag.isEmpty());
       animalBag.add("alligator");
       animalBag.add("bear");
       animalBag.add("bear");
       animalBag.add("cat");
       animalBag.add("dog");
       animalBag.add("elephant");
       System.out.println(animalBag.isEmpty());
       animalBag.add("cat");
       animalBag.add("cat");
       System.out.println(animalBag.getCurrentSize());
       System.out.println(animalBag.remove("bear"));
       System.out.println(animalBag.getCurrentSize());
       System.out.println(animalBag.remove("cat"));
       System.out.println(animalBag.remove("cat"));
       animalBag.add("cat");
       System.out.println(animalBag.remove("gorilla"));
       System.out.println(animalBag.getCurrentSize());
       System.out.println(animalBag.getFrequencyOf("cat"));
       System.out.println(animalBag.contains("gorilla"));
       System.out.println(animalBag.getFrequencyOf("gorilla"));
       animalBag.clear();
       System.out.println(animalBag.getCurrentSize());
       System.out.println(animalBag.remove());

              
   }
}

Answer 1

Yes, you have to create a BagInterface and ArrayBag class having parent child relationship and the program structure will look like this:

public class BagInterface{

.........Implemantation......

}

public class ArrayBag extends BagInterface{

/.........Implementation

}

The child class ArrayBag will inherit the properties from it's parent BagInterface.