没有参数的getter的WSDL类型

I try to write a wsdl file. And I start with defining in the element my future operations. So I need to define a method like getAllObjects. That's why I don't need to set any parameter to getAllObjectsRequest. Could anybody tell me how I must define my message and operations for a method which doesn't declare any inputparameters (like ID in getById).I try to write a wsdl file. And I start with de