How to update customer default paymentMethod in Stripe?

Question

Let's assume that we have created a payment method - pm_xxx. When we create a customer we can attache this method as the default payment method to the customer via java code:

CustomerCreateParams.Builder customerCreateParamsBuilder = CustomerCreateParams.builder()
                    .setEmail(email)
                    .setPaymentMethod('pm_xxx');       
Customer.create(customerCreateParamsBuilder.build());

Unfortunately corresponding api for update customer is not available. So the question is what is preferred way to update customer default payment method in Stripe?

EDIT: Based on @karllekko answer, because My use case is recurring payments so I combine 2 actions: attach customer to payment method:

paymentMethod.attach(PaymentMethodAttachParams.builder().setCustomer(customer.getId()).build());            

and make payment method default for customer invoice:

customer.update(CustomerUpdateParams.builder().setInvoiceSettings(CustomerUpdateParams.InvoiceSettings.builder().setDefaultPaymentMethod(token).build()).build());

Answer 1

The PaymentMethod.attach doc page (1) says this:

To use this PaymentMethod as the default for invoice or subscription payments, set invoice_settings.default_payment_method, on the Customer to the PaymentMethod’s ID.

So you can use the Customer.update API route (2) and fill the invoice_settings attribute.

(1) - https://stripe.com/docs/api/payment_methods/attach

(2) - https://stripe.com/docs/api/customers/update#update_customer-invoice_settings