how to pass no parameters

[terasain]

i am using a client progrom to access a method inside the service, which is deployed in the jboss.net.
the method doesnt take in any parameters and it returns a string

String endpoint =
 "http://10.1.30.57:7070/jboss-net/services/ServiceName";
 String methodName = "servicemethod";
 System.out.println( " I HAVE GOT THE CONNECTION");
 Service service = new Service();
 Call call = (Call) service.createCall();

 call.setTargetEndpointAddress( new java.net.URL(endpoint) );
 call.setOperationName(methodName);

 call.addParameter("name",org.jboss.axis.Constants.XSD_STRING,ParameterMode.IN);
 call.setReturnType(org.jboss.axis.Constants.XSD_STRING);

 //String ret = (String) call.invoke( new Object[] { "AXIS" } );
 String ret = (String) call.invoke( new Object[]{ null } );
 System.out.println(ret);

How do i pass a parameter when my method doesnt accep any. I have tried passing null and it doesnt work.

Thks in advance
Srivats