`Calendar cal = Calendar.getInstance();
cal.set(2019, 4, 10);
Date date = cal.getTime();
IuguConfiguration iuguConfiguration = new IuguConfiguration("IUGU_ID");
InvoiceService invoiceService = new InvoiceService(iuguConfiguration);
Invoice invoice = new Invoice("SOMEEMAIL@XXXX.XXXXX", date, new Item("teste", 1, 100));
// Apenas para forçar a data
invoice.setDueDate(date);
InvoiceResponse response = invoiceService.create(invoice);`
O código acima gera: com.iugu.exceptions.IuguException: Error creating invoice! - StatusCode: [400] / ResponseText: [{"errors":{"due_date":"\u00e9 obrigat\u00f3rio"}}]