Publications.DomiWitt@blogger.com

The ABAP Developer´s Guide to Java

2004-12-27T20:55:00.000+01:00

This is the first book that I have officially been named as an author. The ABAP Developer´s Guide to Java is a book which aims at SAP ABAP Developers, who want/need to get into Java and J2EE development - as the new SAP technology platform SAP NetWeaver heavily relies on J2EE technology.

The quote from the sales catalog reads as follows:

"You already know the ropes in the world of ABAP programming. Now, how can you utilize those finely tuned skills to speed up your journey on the road toward Java proficiency?

This all-new reference book is an indispensable guide for readers who need a rapid and in-depth introduction to Java. Detailed insights and step-by-step instruction help you leverage ABAP development skills you’ve already honed, for a smooth transition to Java. The authors highlight each fundamental aspect pertaining to the development of business applications in both languages, and the differences as well as similarities are analyzed in detail. This must-have resource helps any serious developer learn exclusive techniques to master development tools and objects, application design, application layers and much more. Learn about Beans, OpenSQL for Java, JDBC, Security, and that’s just for starters. This unique book helps you save countless hours of trial and error and avoid costly mistakes while quickly advancing your essential Java skills."

With this book I have been responsible for the overall project management during the decisive phases. Also I have written a majority of the chapters. In this sense my work with this project has produced parts of chapter 2, 4 and most or all of chapters 5 through 7. Although the book was written mostly in a hurry and besides daily work, I am pretty happy with the result.

English Releases

buy at SAP-Press.com
buy at Amazon.de

German Releases

buy at SAP-Press.de
buy at Amazon.de

Diploma Thesis - Web Application Design

2004-12-27T20:47:00.000+01:00

A Component Framework Based On Web Services

Web Services are an XML-based set of technologies to enable remote function calls over about any web-related transport protocol like HTTP, SMTP or FTP. As it is a specification based on the maxim of extensibility and customizability this technology is also suitable for communication across platforms and programming languages. The key feature that both IT analysts and the businesses put their hopes on is the possibility of supporting the automation of business processes even across company borders and the aggregation of these processes to complete workflows that follow the mechanism of recursive composition which means that a workflow itself can be exposed as a business process to be reused within a more comprehensive system.

All concepts of Web Services are based on standards that are developed and confirmed
by consortiums of independent organizations like the W3C and OASIS consulted by the
industry leaders of infrastructure and ERP software like Microsoft, IBM, SAP, VeriSign and many more. While the terms of service location, registration, data transportation across systems, formatting and embedding into other protocols has been dealt with successfully, security, transaction and meta-descriptive standards have yet to be finalized.

On the basis of this scenario this document develops a concept of a distributable,
scalable, reusable and extensible component architecture that uses Web Services as its foundations. The theoretical model is then implemented using the server-sided scripting language PHP that itself has become the most popular server-sided scripting language for web-related purposes over the last three years. The component architecture thereby adds a model for business logic, encapsulated within distributable entities to the overall concept of multi-tiered application design, like it is popular with enterprise level applications built on the foundations of e.g. J2EE, Microsoft .NET or SAP NetWeaver.

The applicability of the concepts and the model presented is proved through both
example implementations of the basic features and a case study that creates a context
for a Web Service based application.

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Study Paper - Web Application Development

2004-11-27T15:04:00.000+01:00

Concepts and Technologies

In a client-server scenario like browser based application development, the Three Tier Model is of extreme importance and is therefore base of the technological discussion within this document.

With the first tier - the presentation layer - accessibility issues and the need to serve client-specific content is discussed. It is explained how template technology helps with the maintenance process of a web-based application and how it is incorporated efficiently into the concurrent development model.

On behalf of the second – the application layer - the overcoming of the statelessness of HTTP is delineated together with related issues such as handling user sessions. In that context also security considerations are discussed at length as they remain very critical to web-based applications, mainly operating on user submitted personal data.

For the data tier the usability of file-based systems is evaluated against database
systems. In this context it is important to understand the meaning of company-spanning data exchange. XML and its transformation via XSLT will be outlined as will unified formats for data exchange. As automated communication of software system is becoming more and more important several methods to do so including SOAP and web-services will be introduced.

After dealing with the technological aspect this document will dive into system
engineering and design. As the main factors influencing web-based application design are the business plan, estimates, communication, usability and maintainability they will be analyzed as to their current importance.

The last topic will deal with the unstructured, the structured and the extreme
programming approaches common in application design. A discussion of their respective
advantages and drawbacks is followed by a concluding assessment of each.

Altogether this document is supposed to give the reader an overview of today’s technologies and concepts dealing with application design in general and web-based application design in particular.

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