In this third and final part of the book, we use the industry standards, technologies, and best practices described in the previous two sections to build real world enterprise Web services and applications. The two chapters in this section are filled with source code and are a detailed step-by-step guide to developing Web services and client applications that use Web services.
Any application can be put together in a haphazard manner, but these applications are almost never appropriate for a real world production environment. Real world enterprise applications must be easy to develop, even easier to customize and maintain, support transactional requirements, allow seamless porting to multiple devices and platforms, and so on. Enterprise Web Services and Web Services-based applications cannot be developed by just reading through the SOAP or WSDL standards. Developers must understand a number of different standards and technologies and, more importantly, their inter-relationships and best practices for their use.
Chapter 12: Real World Web Service Application Development Foundations. In Chapter 12, we go step-by-step and develop a Web services application as well as the consumed Web services using only the vanilla Web services technologies as described in Section One. We not only describe how to build the system and provide the source code, but we also discuss how to deploy the Web services and application onto the Tomcat application server and the Axis SOAP server (both of which are freely available). We build the application in this chapter in an effort to illustrate that the core Web services platform is simply a set of enabling technologies for XML-based distributed computing.
Chapter 13: Real World Web Service Application Development Advanced Technologies. The exchange of XML messages between businesses is only the tip of the iceberg as far as enterprise computing is concerned. To enable true enterprise-level computing with Web services, we must address the enterprise requirements that enable dependable applications to be built. In Chapter 13 we address these requirements by adding security, transactionality, workflow, and mobility into the application we developed in Chapter 12.
Chapter 14: Epilogue. We have seen a number of important concepts in Web services, and in Chapters 12 and 13 we have seen how those concepts can be put into practice. In Chapter 14, we put that knowledge into perspective, summarizing the important points of each technology and offering advice on how these technologies may evolve as Web services practice matures.
After reading Part 3, you will have a thorough understanding of the steps necessary to build and deploy Web services and client applications that meet enterprise requirements.