Produce a data map with order record and product total sum

ProductTotalSum.java

    @RequestMapping("/product-total-sum")
    public Map<Order, Double> getProductTotalSumByOrder() {
         return orderRepo.findAll().stream().collect(Collectors.toMap(o -> new Order(o.getId(), o.getOrderDate(),
                 o.getDeliveryDate(), o.getStatus()), o -> o.getProducts().stream().mapToDouble(p ->
                 p.getPrice()).sum()));
    }