Strange about invoking web service method declared “string method(void)”;

Question

Dear forum readers
I’m experimenting with OpenESB and web services. I’ve create a simple web service using NetBeans 6.1. The method consists of a single method, getTime, that is declared:
String getTime()
My current experiment is to invoke this method from a BPEL-process using the “Invoke” process object. The strange thing is that it seems like I have to provide a “dummy” inbound variable from the BPEL-designer even though the method doesn’t take any parameters. I include a snippet from the BPEL process below which includes the section where I set the dummy GetTimeIn-variable and then invokes the WS method getTime().
<assign name="Assign2">
<copy>
<from>'DummyValue'</from>
<to variable="GetTimeIn" part="parameters"/>
</copy>
</assign>
<invoke name="Invoke1" partnerLink="PartnerLink1" operation="getTime" xmlns:tns="http://ws/" portType="tns:MyWebService" outputVariable="GetTimeOut" inputVariable="GetTimeIn"/>
If I don’t initiate the dummy variable or remove it altogether, I can’t successfully call the method. If I include the dummy in-parameter the call works just fine and I get back the current time as a string.
I must admit that I’m still a rookie to web services, especially when calling them from a BPEL-process, so it may be a very trivial reason for this behaviour. Anyway, any help on this matter would be greatly appreciated.
Regards, Ola

Answer 1

Thank you both for the response. Regarding Rennay’s posting I have an additional question. When I create a new web service I don't have the "Document Literal" option nor a "Concrete Configuration" tab. I've created the web service using the "Web Application" project type and then adding a web service using the "Web Service..." wizard. This wizard doesn't have the configuration properties you mention, but if I add a WSDL-file to a BPEL-project the wizard has the properties you mention.
Is it possible to create a web service, programmed as an ordinary Java-class, from an existing WSDL-file? In that case it may solve the problem with the “Document Literal” property. Currently I don’t know any other way to create such a web-service other than the through the web service wizard in a web application project. Of course, it’s possible to craft it from scratch but that’s to much work to be practical.
Regards, Ola