When it came time for me to tackle my first web service implementation I ran into a lot of problems. Here I will write a series of articles to address the questions and problems I encountered in hopes of helping you get started in developing web services faster than I did. The following example will show you how to create a web service using JAX-WS and packaged as a servlet.

A Simple Service

To start out you should create an interface defining your business methods. I will keep the implementation extremely simple so we can focus on the details of web services. Here's our interface named SimpleServiceWS

public interface SimpleServiceWS {  

     public String simpleMethod();  

}

The next step is to create a plain java class (POJO) which implements this interface. I'll name it SimpleServiceImpl

public class SimpleServiceImpl implements SimpleServiceWS 

{  

   public String simpleMethod() { return "Simple response"; }  

}

Please note that it is not required to create and implement an interface and almost every web service example I found did not do so. I feel it is good practice and consistent with Java programming practices to program against interfaces.

The final keyword is one that I find is under utilized. Use final in your projects as a means of defensive programming. If you are unfamiliar with this keyword here is a great article on its usage.

Renaud Waldura’s The Final Word On the final Keyword .

I received an email from someone who liked my technical blog and invited me to join JTraining. So here I am. I look forward to sharing my knowledge with and learning from the members of this community.