Accepting any object and returning the object

I have been tinkering with generic methods in Java but still haven't figured out a way to optimize this code. Here I need to write similar piece of code for both plan and add-on.

public Set<SubscriptionDto> getCustomerSubscriptions(Integer customerId) {
    Set<SubscriptionDto> subscribedProducts = new HashSet<>();
    Set<PlanDto> subscribedPlans = new HashSet<>();
    Set<AddonDto> subscribedAddons = new HashSet<>();
    Double totalPrice = (double) 0;
    try {
        List<Subscription> subscriptions = subscriptionService.findByCustomerId(customerId);
        if (subscriptions != null) {
            for (Subscription subscription : subscriptions) {

                SubscriptionDto subscriptionDto = new SubscriptionDto();

                // Get the Plans subscribed for particular product
                for (SubscribedLicense subscribedLicense : subscription.getSubscribedLicenses()) {

                    // Get Plan
                    if (subscribedLicense.getLicenseType().equals(LicenseTypeEnum.PLAN.getDescription())) {

                        Plan plan = planService.findById(subscribedLicense.getLicenseTypeId());

                        PlanDto planDto = new PlanDto();
                        planDto.setPlanName(plan.getName());
                        planDto.setNoOfFreeLicense(subscribedLicense.getNoOfFreeLicense());
                        planDto.setNoOfLicense(subscribedLicense.getNoOfLicense());

                        subscribedPlans.add(planDto);

                        // Calculate Price
                        PlanPrice planPrice = planPriceService.findById(subscribedLicense.getLicenseTypePriceId());
                        if (planPrice != null) {
                            totalPrice = totalPrice + (planDto.getNoOfLicense() * planPrice.getPrice());
                        }
                    }

                    // Get Addon
                    if (subscribedLicense.getLicenseType().equals(LicenseTypeEnum.ADDON.getDescription())) {

                        Addon addon = addonService.findById(subscribedLicense.getLicenseTypeId());

                        AddonDto addonDto = new AddonDto();
                        addonDto.setAddonName(addon.getName());
                        addonDto.setNoOfFreeLicense(subscribedLicense.getNoOfFreeLicense());
                        addonDto.setNoOfLicense(subscribedLicense.getNoOfLicense());

                        subscribedAddons.add(addonDto);

                        // Calculate Price
                        AddonPrice addonPrice = addonPriceService
                                .findById(subscribedLicense.getLicenseTypePriceId());
                        if (addonPrice != null) {
                            totalPrice = totalPrice + (addonDto.getNoOfLicense() * addonPrice.getPrice());
                        }
                    }

                }

                // Add price for the subscription
                subscriptionDto.setTotalPrice(totalPrice);

                // Add Product Name
                subscriptionDto.setProductName(subscription.getProduct().getName());

                // Add Product Image
                subscriptionDto.setProductImage(subscription.getProduct().getImageName());

                // Add Billing Period Type
                subscriptionDto.setBillingPeriodType(subscription.getBillingPeriodType());

                // Add plans customer has subscribed
                if (!subscribedPlans.isEmpty()) {
                    subscriptionDto.setPlanDtos(subscribedPlans);
                }

                // Add addons customer has subscribed
                if (!subscribedAddons.isEmpty()) {
                    subscriptionDto.setAddonDtos(subscribedAddons);
                }

                // Add subscriptions to subscriptions list
                subscribedProducts.add(subscriptionDto);
            }
        }

        return subscribedProducts;

    } catch (Exception ex) {

    }
}