How to sort an array of objects using MergeSort in java without comparator

Question

I need to sort a huge array of objects. Each object contains a number. I need to sort it by that number, but I can't use a comparator. Is it possible to do it using a mergesort algorithm?

Answer 1

As long as each object has a way to be compared (typically done in a 'compareTo(T other)' function), mergesort is a viable solution.

EDIT: More thoroughly, it would look something like this:

public int compareTo(T other){
    if this.getNumber() == other.getNumber(){
        return 0;
    }
    else if this.getNumber() > other.getNumber(){
        return 1;
    }
    else{
        return -1;
    }
}