19 JSR 172: Web Services Support

19.1 Generating Stub Files from WSDL Descriptors

The NetBeans IDE provides a stub generator that automates creating source code for accessing web services that conform to the J2ME Web Services Specification. You can add stubs to any MIDP application.

The following is a general procedure for adding stubs:

1. In the Projects window, expand the tree for a project.

2. Launch the Java ME Web Service Client wizard:

   Right-click on the Source Packages node and select New > Java ME Web Service Client...

3. In the Generate J2ME Webservice Stub page, you can either:

   • Click Running Web Service and enter the URL for the WSDL

   • Click Specify the Local filename for the retrieved WSDL and browse to a file on your system.

   In either case, you must enter a Package name, then click Finish. The new package appears in the project and includes an interface file and a stub file.

4. You can now edit your source files to call the content the stub provides, then build and run.

   See Section 19.2, "Creating a New Mobile Web Service Client" for a step by step process, or see Section 19.3, "Run JSR172Demo" and view the demo source files.

19.2 Creating a New Mobile Web Service Client

This sample procedure creates a new project and adds a web service client. However, you can add a web service client to any MIDP project, it does not have to be new.

1. Select File > New Project, choose MIDP application, and click Next. Name your project and ensure Create Hello MIDlet is checked. Click Finish.

2. Right-click on the Source Packages node and select New > Java ME Web Service Client...

3. In the Generate J2ME Webservice Stub page:

   • Click Running Web Service and in the WSDL URL field, enter:

     http://www.xmlme.com/WSShakespeare.asmx?WSDL

   • In the Package field, enter testws. This is the package name.

   Click Finish. The new package appears in Source Packages and includes Shakespeare.java and Shakespeare_Stub.java.

4. Edit HelloMIDlet.java as follows:

   • At the beginning, add the following import declaration:

     import testws.*

   • Locate the startApp() method and replace its contents with the following code:

     String text;
     Shakespeare s = new Shakespeare_Stub();
     try
     {
         text = s.GetSpeech("Romeo");
     }catch(java.rmi.RemoteException rex)
     {
          text = "error";
          System.out.println(rex.getMessage());
     }
     TextBox t = new TextBox("Hello", text, 2048, 0);
     t.addCommand(exitCommand);
     t.setCommandListener(this);
     display.setCurrent(t);
     

5. Build and run the project. You see a quote from Shakespeare's Romeo and Juliet on the device screen.

   You can vary the above procedure to use a local WSDL file. Open the following web page in a browser:

   http://www.xmlme.com/WSShakespeare.asmx?WSDL

   Save it to a local file. For example, c:\ws\WSShakespeare.wsdl. Follow the procedure above, except at Step 4, specify the local file name.

19.3 Run JSR172Demo

JSR172Demo shows how to access a web service from a MIDlet. The web service is already running on an Internet server, and it conforms to the J2ME Web Services Specification.

If you are using a proxy server, you must configure the emulator's proxy server settings as described in Section 3.4, "Configuring the Web Browser and Proxy Settings". Build and run the example.

JSR172Demo contains a single MIDlet named Server Script. Launch it and follow the prompts. You can browse through simulated news headlines, all of which are retrieved from the web service.