Always Crispy

So Web Services have been around for a while now and one would think that the popular packages out there would support most any service. Well unfortunately, that is a bad assumption to make. That is because of how long Web Services have existed. Some earlier versions employed a variation of the SOAP message that we use today called XML-RPC. Very few contemporary Web Service packages support XML-RPC yet even now, you will run into someone using it, like I did at work.

I found that Axis 1.4 works pretty much out of the box for these older style Web Services. Axis2, like the rest though, does not support XML-RPC. 

To create a client, you will be best served by using the WSDL2Java utility. To use it, you will need to make sure the following jars are in your classpath; they come packaged in the Axis 1.4 download so you don’t have to google for them.

• axis.jar
• jaxrpc.jar
• saaj.jar
• commons-logging-1.0.4.jar
• commons-discovery-0.2.jar
• wsdl4j-1.5.1.jar

Once you have added those jars to your classpath, you can let Axis do most of the work for you in creating a client. For this example, we are going to build a client that gets the weather from the global weather Web Service. This Web Service is pretty basic so it is good for learning how to make a client however, its uptime can be spotty at times.

Here are the steps for creating a clients.

Step 1: Download the globalweather.wsdl. This file contains information describing the Web Service.

Step 2: Run the following command
java org.apache.axis.wsdl.WSDL2Java globalweather.wsdl

This Axis utility will generate a Java package from the wsdl necessary for interacting with the Web Service. This code will be layout out in the directory where you ran the utility and at the time of writing this article should have to following structure
NET/webserviceX/www/

Step 3: Copy the code you generated in Step 2 to your client’s working directory. You might not need to do this step if you are going to write your client in the same directory in which you generated the package. If you are using Eclipse or any IDE though, you will want to copy the NET directory into one of your source code folders. I use Eclipse so I literally dragged and dropped it.

Step 4: Create a client class. The code below is a simple client that gets the weather for New York.

import NET.webserviceX.www.*;
public class HelloWeather {
    public static void main(String[] args) throws Exception {
        GlobalWeatherLocator locator = new GlobalWeatherLocator();
        GlobalWeatherSoap globalWeatherSoap = locator.getGlobalWeatherSoap();
        System.out.println("Weather for New York");
        System.out.println(globalWeatherSoap.getWeather("New York", "United States"));
    }
}

Axis hides a lot of the boiler plate work involved in a Web Service and it is pretty simple to use. The only complexity that you will encounter is when the Web Services you use get complex and generally those ones have some support documentation that explains what all the end points are and how you should use them.