Java Error: Comparator is not abstract and does not override abstract method compare(Object,Object) in Comparator

I have a Sorting.java file, with the following structure:

public class Sorting {
    public static <T> void mergeSort(T[] arr, Comparator<T> comparator) {
    (...)
    }
}

My goal is to test the mergeSort() method in a separate Driver.java file.

To that effect, here is what I included in that driver file:

import java.util.Comparator;
import java.io.*;
import java.util.*;

public class Driver {
    public static void main(String[] args) {
        int[] testMergeSort1 = { 9, 13, 5, 6, 12, 10, 3, 7, 2, 8, 0, 15, 1, 4, 14, 11 };
        mergeSort(testMergeSort1, IntegerComparator);
        System.out.println(Arrays.toString(testMergeSort1));
    }
}

And, per the accepted answer to this similar question, I added the following implementation of an Integer comparator to that same Driver.java file:

public class IntegerComparator implements Comparator {
    public int compare(Integer a, Integer b) {
        return a.intValue() - b.intValue();
    }

    public int equals(Object obj) {
        return this.equals(obj);
    }
}

However, when I compile Driver.java, I get the following error:

Driver.java:33: error: Driver.IntegerComparator is not abstract and does not override abstract method compare(Object,Object) in Comparator
    public class IntegerComparator implements Comparator {
           ^
Driver.java:38: error: equals(Object) in Driver.IntegerComparator cannot implement equals(Object) in Comparator
        public int equals(Object obj) {
                   ^
  return type int is not compatible with boolean

Any guidance on how to proceed to test the mergeSort() method from the Sorting.java file in the separate Driver.java file would be appreciated.

>Solution :

Try to implement a generic Comparator<Integer> and add @Override annotations, to check if you actually override the method in Comparator.

public class IntegerComparator implements Comparator<Integer> {
    @Override
    public int compare(Integer a, Integer b) {
        return a.intValue() - b.intValue();
    }
}