Non-Leetcode Questions: k-Nearest Points to Origin

Non-Leetcode Questions: k-Nearest Points to Origin
Find the K closest points to the origin in 2D plane, given an array containing N points. You can assume K is much smaller than N and N is very large.
O(nlogk)

public List<Point> kNearestToOrigin(List<Point> set, int k){
        Comparator<Point> comparator = new Comparator<Point>(){
            @Override
            public int compare(Point a, Point b){
                if(Math.pow(a.x,2)+Math.pow(a.y,2) > Math.pow(b.x,2)+Math.pow(b.y,2))
                    return -1;
                else if(Math.pow(a.x,2)+Math.pow(a.y,2) < Math.pow(b.x,2)+Math.pow(b.y,2))
                    return 1;
                else
                    return 0;
            }
        };
        List<Point> rlst = new ArrayList<Point>();
        PriorityQueue<Point> heap = new PriorityQueue<Point>(set.size(), comparator);
        for(int i = 0;i < k && i < set.size();i++)
            heap.add(set.get(i));
        for(int i = k;i < set.size();i++){
            if(comparator.compare(set.get(i),heap.peek()) > 0){
                heap.poll();
                heap.add(set.get(i));
            }
        }
        while(!heap.isEmpty()){
            rlst.add(heap.poll());
        }
        return rlst;
    }
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