Parameter versus no parameter

[to...@gsk.com]

Apologies for the length of this but I wanted to include WSDL and 
generated code to give a complete picture.

I've been trying to get simple Java client code generated for a service 
that has no input but does have some output. Defining an input message 
with a part that has an empty element produces Java code, via WSDL2Java, 
that works fine, provided I pass a null parameter. The service method in 
the generated stub is trying to pass back the Java object I want and the 
Axis code can deserialize it fine.

However, if I define an input message with no parts, the generated stub 
includes a no-arguments method, which is what I want, but it tries to 
return an object typed to a different class, the class generated to 
represent to SOAP response body. However, the actual response from the 
service is the same in both cases, so the no-arguments method fails with a 
class cast exception.

It seems that the Axis code is trying to deserialize the response as 
though all the elements below the body root are attributes of the root 
class. I've noticed that the generated stub for the no-arguments version 
sets the operation as document/literal instead of wrapped/literal, and 
sets different return properties for the operation. If I alter the 
generated stub to match the stub generated for the single argument version 
(apart from keeping the no-argument version of the service method), then 
it works fine.

Does anyone know how to get the Axis WSDL2Java tool to generate working 
code for the no-arguments version? I've included the WSDL and generated 
code below, in case my explanation is not clear.

Thanks for any help.
Tony


The WSDL (without the XML/SOAP namespace declarations) for the single 
argument version is something like:

<?xml version="1.0" encoding="utf-8"?>
<definitions xmlns:services="uri:myServicesNameSpace" 
xmlns:mine="uri:myNameSpace" targetNamespace="uri:myServicesNameSpace">
  <types>
    <xs:schema targetNamespace="uri:myNameSpace" 
xmlns:my="uri:myNameSpace" elementFormDefault="qualified" 
attributeFormDefault="unqualified">
      <xs:complexType name="myObjectType">
        <xs:sequence>
          <xs:element name="id" type="xs:integer" nillable="false"/>
          <xs:element name="mf" type="xs:string" nillable="false"/>
        </xs:sequence>
      </xs:complexType>
      <xs:complexType name="myObjectList">
        <xs:sequence>
          <xs:element ref="my:thing" maxOccurs="unbounded"/>
        </xs:sequence>
      </xs:complexType>
      <xs:element name="thing" nillable="false" type="my:myObjectType"/>
      <xs:element name="things" nillable="false" type="my:myObjectList"/> 
    </xs:schema>
    <xs:schema elementFormDefault="qualified" 
targetNamespace="uri:myServicesNameSpace">
      <xs:complexType name="serviceResponse">
        <xs:sequence>
          <xs:element ref="mine:things"/>
        </xs:sequence>
      </xs:complexType>
      <xs:element name="getObjects">
      </xs:element>
      <xs:element name="objectDescriptions" 
type="services:serviceResponse">
      </xs:element>
    </xs:schema>
  </types>
  <message name="getObjectsRequest">
    <part name="getObjects" element="services:getObjects"/>
  </message>
  <message name="getObjectsReply">
    <part name="getObjects" element="services:objectDescriptions"/>
  </message>
  <portType name="objectsPortType">
    <operation name="getObjects">
      <input message="services:getObjectsRequest"/>
      <output message="services:getObjectsReply"/>
    </operation>
  </portType>
  <binding name="ObjectsBinding" type="services:objectsPortType">
    <soap:binding style="document" 
transport="http://schemas.xmlsoap.org/soap/http"/>
    <operation name="getObjects">
      <soap:operation soapAction="getObjects" style="document"/>
      <input>
        <soap:body use="literal"/>
      </input>
      <output>
        <soap:body use="literal"/>
      </output>
    </operation>
  </binding>
  <service name="ObjectsLookup">
    <port name="ObjectsPort" binding="services:ObjectsBinding">
      <soap:address 
location="http://my.com:8080/axis/services/ObjectsLookup"/>
    </port>
  </service>
</definitions>

The relevant sections of the generated stub are:

public class ObjectsBindingStub extends org.apache.axis.client.Stub 
implements myServicesNameSpace.ObjectsPortType {

    ...

    static {
        _operations = new org.apache.axis.description.OperationDesc[1];
        org.apache.axis.description.OperationDesc oper;
        oper = new org.apache.axis.description.OperationDesc();
        oper.setName("getObjects");
        oper.addParameter(new 
javax.xml.namespace.QName("uri:myServicesNameSpace", "getObjects"), new 
javax.xml.namespace.QName("http://www.w3.org/2001/XMLSchema", "anyType"), 
java.lang.Object.class, org.apache.axis.description.ParameterDesc.IN, 
false, false);
        oper.setReturnType(new 
javax.xml.namespace.QName("uri:myNameSpace", "myObjectList"));
        oper.setReturnClass(myNameSpace.MyObjectList.class);
        oper.setReturnQName(new 
javax.xml.namespace.QName("uri:myNameSpace", "things"));
        oper.setStyle(org.apache.axis.enum.Style.WRAPPED);
        oper.setUse(org.apache.axis.enum.Use.LITERAL);
        _operations[0] = oper;

    }

    ....

    public myNameSpace.MyObjectList getObjects(java.lang.Object 
getObjects) throws java.rmi.RemoteException {
        if (super.cachedEndpoint == null) {
            throw new org.apache.axis.NoEndPointException();
        }
        org.apache.axis.client.Call _call = createCall();
        _call.setOperation(_operations[0]);
        _call.setUseSOAPAction(true);
        _call.setSOAPActionURI("getObjects");
        _call.setEncodingStyle(null);
        _call.setProperty(org.apache.axis.client.Call.SEND_TYPE_ATTR, 
Boolean.FALSE);
        _call.setProperty(org.apache.axis.AxisEngine.PROP_DOMULTIREFS, 
Boolean.FALSE);
 
_call.setSOAPVersion(org.apache.axis.soap.SOAPConstants.SOAP11_CONSTANTS);
        _call.setOperationName(new 
javax.xml.namespace.QName("uri:myServicesNameSpace", "getObjects"));

        setRequestHeaders(_call);
        setAttachments(_call);
        java.lang.Object _resp = _call.invoke(new java.lang.Object[] 
{getObjects});

        if (_resp instanceof java.rmi.RemoteException) {
            throw (java.rmi.RemoteException)_resp;
        }
        else {
            extractAttachments(_call);
            try {
                return (myNameSpace.MyObjectList) _resp;
            } catch (java.lang.Exception _exception) {
                return (myNameSpace.MyObjectList) 
org.apache.axis.utils.JavaUtils.convert(_resp, 
myNameSpace.MyObjectList.class);
            }
        }
    }

}

This is all fine. However, when I alter the WSDL so that the input message 
becomes:

  <message name="getObjectsRequest">
  </message>

Then the relevant part of the generated stub is something like this:

public class ObjectsBindingStub extends org.apache.axis.client.Stub 
implements myServicesNameSpace.ObjectsPortType {

    ...

    static {
        _operations = new org.apache.axis.description.OperationDesc[1];
        org.apache.axis.description.OperationDesc oper;
        oper = new org.apache.axis.description.OperationDesc();
        oper.setName("getObjects");
        oper.setReturnType(new 
javax.xml.namespace.QName("uri:myServicesNameSpace", "serviceResponse"));
        oper.setReturnClass(myServicesNameSpace.ServiceResponse.class);
        oper.setReturnQName(new 
javax.xml.namespace.QName("uri:myServicesNameSpace", 
"objectDescriptions"));
        oper.setStyle(org.apache.axis.enum.Style.DOCUMENT);
        oper.setUse(org.apache.axis.enum.Use.LITERAL);
        _operations[0] = oper;

    }

    ...

    public myServicesNameSpace.ServiceResponse getObjects() throws 
java.rmi.RemoteException {
        if (super.cachedEndpoint == null) {
            throw new org.apache.axis.NoEndPointException();
        }
        org.apache.axis.client.Call _call = createCall();
        _call.setOperation(_operations[0]);
        _call.setUseSOAPAction(true);
        _call.setSOAPActionURI("getObjects");
        _call.setEncodingStyle(null);
        _call.setProperty(org.apache.axis.client.Call.SEND_TYPE_ATTR, 
Boolean.FALSE);
        _call.setProperty(org.apache.axis.AxisEngine.PROP_DOMULTIREFS, 
Boolean.FALSE);
 
_call.setSOAPVersion(org.apache.axis.soap.SOAPConstants.SOAP11_CONSTANTS);
        _call.setOperationName(new javax.xml.namespace.QName("", 
"getObjects"));

        setRequestHeaders(_call);
        setAttachments(_call);
        java.lang.Object _resp = _call.invoke(new java.lang.Object[] {});

        if (_resp instanceof java.rmi.RemoteException) {
            throw (java.rmi.RemoteException)_resp;
        }
        else {
            extractAttachments(_call);
            try {
                return (myServicesNameSpace.ServiceResponse) _resp;
            } catch (java.lang.Exception _exception) {
                return (myServicesNameSpace.ServiceResponse) 
org.apache.axis.utils.JavaUtils.convert(_resp, 
myServicesNameSpace.ServiceResponse.class);
            }
        }
    }

}