11.3. Web Services Clients

We will now turn our attention from providing web services to consuming them.

11.3.1. A JAX-RPC client

The full JAX-RPC programming model is available to J2EE applications and clients. We won't cover the full range of client programming techniques, but we swill look briefly at the client we've used so far to test the web services we've deployed. The client, shown in the following listing, illustrates the dynamic proxy invocation mechanism. 
package org.jboss.ws.client;

import org.jboss.ws.hello.Hello;

import javax.xml.rpc.Service;
import javax.xml.rpc.ServiceFactory;

import javax.xml.namespace.QName;

import java.net.URL;

public class HelloClient
{
    public static void main(String[] args)
        throws Exception
    {
        String urlstr   = args[0];
        String argument = args[1];

        System.out.println("Contacting webservice at " + urlstr);

        URL url =  new URL(urlstr);

        QName qname = new QName("http://hello.ws.jboss.org/",
                                "HelloService");

        ServiceFactory factory = ServiceFactory.newInstance();
        Service        service = factory.createService(url, qname);

        Hello          hello   = (Hello) service.getPort(Hello.class);

        System.out.println("hello.hello(" + argument + ")");
        System.out.println("output:" + hello.hello(argument));
    }
}
This JAX-RPC client uses the Hello service endpoint interface and creates a dynamic proxy to speak to the service advertised by the WSDL at the URL that is passed in as a command line argument. For illustrative purposes, we'll show another variation of web services invocation that doesn't use the service endpoint interface. This is known as the Dynamic Invocation Interface (DII). Using DII, it is possible to refer to a specific port and operation by name. Think of it as reflection for web services. The client code is shown in the following listing. 
package org.jboss.ws.client;

import org.jboss.ws.hello.Hello;

import javax.xml.rpc.Service;
import javax.xml.rpc.ServiceFactory;
import javax.xml.rpc.Call;

import javax.xml.namespace.QName;

import java.net.URL;

public class HelloClientDII
{
    public static void main(String[] args)
        throws Exception
    {
        String urlstr   = args[0];
        String argument = args[1];

        System.out.println("Contacting webservice at " + urlstr);

        URL url =  new URL(urlstr);

        String ns        = "http://hello.ws.jboss.org/";
        QName  qname     = new QName(ns, "HelloService");
        QName  port      = new QName(ns, "HelloPort");
        QName  operation = new QName(ns, "hello");

        ServiceFactory factory = ServiceFactory.newInstance();
        Service        service = factory.createService(url, qname);
        Call           call    = service.createCall(port, operation);

        System.out.println("hello.hello(" + argument + ")");
        System.out.println("output:" + call.invoke(new Object[] {argument}));
    }
}
The following two commands can be used to run the DII client against both the JSE and EJB web services we have created. 
[examples]$ ant -Dchap=ws -Dex=1b run-example
[examples]$ ant -Dchap=ws -Dex=2b run-example
Note: When accessing a remote client using the JBossWS client code, is is necessary to set the java.endorsed.dirs system property to the lib/endorsed directory under your JBoss installation. For example: -Djava.endorsed.dirs=/path/to/jboss-4.0.4/lib/endorsed.