Creating a JAX-WS Web Service

JAX-WS, the new web service implementation replacing JAX-RPC; provides very interesting features.\\ It is amazing how a web service can be generated and published.\\ Let's see an example of a web service that allows pulling news headlines from EGJUG.\\ We will start by creating an XML schema that is the messaging contract between the client and the server: {{{ }}} Very simple, a request will specify the portal name it needs to pull news from, and the response will return those headlines if any. Now let's create a WSDL for our web service: {{{

}}} There is only one operation here: 'getHeadLines'. The operation will hold the requested news portals as an input. Starting from a WSDL, JAX-WS provides some handy tools to generate all web service artifacts, a batch file named 'wsimport.bat' ('wsimport.sh' for Unix) can be found under the 'bin' directory of the distribution, a simple command line will do the job: {{{ wsimport -keep -verbose -s src -d classes -wsdllocation http://127.0.0.1:7777/services/simple?wsdl xml/simple-service.wsdl }}} This will generate all needed artifacts. XML binding is generated using JAXB 2.0. No more different binding libraries like JAX-RPC. Now let's implement our 'NewsHeadLines' service: {{{ @javax.jws.WebService(endpointInterface = "org.egjug.services.simple.NewsHeadLines") public class SimpleService{ @WebMethod @WebResult(name = "response", targetNamespace = "http://www.egjug.org/xml/ns/news", partName = "response") public Response getHeadLines( @WebParam(name = "request", targetNamespace = "http://www.egjug.org/xml/ns/news", partName = "request") Request request){ Response response = new Response(); List responsePortals = response.getPortal(); List requestedPortals = request.getPortal(); for(Portal rqp : requestedPortals){ Portal rsp = new Portal(); rsp.setName(rqp.getName()); addHeadLines(rsp); responsePortals.add(rsp); } return response; } private void addHeadLines(Portal rsp){ List headlines = rsp.getHeadLine(); switch(rsp.getName()){ case TSS: headlines.add("BemBem Software just released a new AJAX product, this release can make coffee"); headlines.add("Hani Sulieman interview, watch this big mouth today"); break; case IBM: headlines.add("IBM releases another buggy Rational product 'Rational XeSdf0I', download and crash today"); headlines.add("IBM releases a DB2 version for free, go get Oracle's free one"); break; } } } }}} Of course news wouldn't be statically embedded into the code; this is just for testing the service. As mentioned earlier, one powerful feature of this API is the simplicity of web services publishing, here is an example: {{{ public class SimplePublisher{ public static Source load(String uri){ Source source = null; try{ source = new SAXSource(new InputSource(new FileInputStream(uri))); source.setSystemId(new File(uri).toURL().toString()); } catch(FileNotFoundException e){ e.printStackTrace(); } catch(MalformedURLException e){ e.printStackTrace(); } return source; } public static void publish(){ Provider provider = Provider.provider(); List metadata = new ArrayList(); metadata.add(load("xml/egjug-news.xsd")); metadata.add(load("xml/simple-service.wsdl")); SimpleService simple = new SimpleService(); Endpoint endpoint = provider.createEndpoint(SOAPBinding.SOAP11HTTP_BINDING, simple); endpoint.setMetadata(metadata); endpoint.publish("http://127.0.0.1:7777/services/simple"); } public static void main(String...args){ publish(); } } }}} This is all what we need to do to publish the service, no application server, no servlet configuration, no deployment, just a simple API, but the API also supports running inside a container as well. To test our service, let's send a SOAP message. You can use any client or code your own: {{{ }}} Here is the reply for this message: {{{ BemBem Software just released a new AJAX product, this release can make coffee Hani Sulieman interview, watch this big mouth today }}} |> So simple, start writing your web service today!!

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