How to access parameters when building web services?

This is my first time developing a web service with IDEA, so please be gentle.

I followed www.jetbrains.com/idea/docs/Web_Services_with_IntelliJ_IDEA.pdf

and created a hello world web service. I can access it in browser using http://localhost:8080/services/HelloWorld?method=sayHelloWorldFrom

Now then web service method sayHelloWorldFrom, takes a parameters "from"

  public String sayHelloWorldFrom(String from) {
    String result = "Hello, world, from " + from;
    System.out.println(result);
    return result;
  }


How can I specify the value of from using the URL?  I tried http://localhost:8080/services/HelloWorld?method=sayHelloWorldFrom&from=test and it generates an error message:

faultcode: soapenv:Server.userException
faultstring:org.xml.sax.SAXException: SimpleDeserializer encountered a child element, which is NOT expected, in something it was trying to deserialize.

Can you please assist me? thanks!

Sanders