I use such kind of a Map population thanks to Java 9. In my honest opinion, this approach provides more readability to the code.
public static void main(String[] args) {
Map<Integer, Point2D.Double> map = Map.of(
1, new Point2D.Double(1, 1),
2, new Point2D.Double(2, 2),
3, new Point2D.Double(3, 3),
4, new Point2D.Double(4, 4));
map.entrySet().forEach(System.out::println);
}