Test yourself. URL https://www.sandbox.paypal.com/wsdl/PayPalSvc.wsdl
paypal.sandbox is reference for sandbox web service*/
You will see here this web services exposes class */
class AddressType
paypal.sandbox.AddressType addressType = new paypal.sandbox.AddressType();
addressType.AddressID = "Your Address ID";
Another class DoDirectPaymentResponseType
paypal.sandbox.DoDirectPaymentResponseType response = new paypal.sandbox.DoDirectPaymentResponseType();
response.TransactionID = "25554d";
How it possible that multiple classes exposes in single webservice