1. Overview

As the name implies, AMDD is the agile version of Model Driven Development (MDD). MDD is an approach to software development where extensive models are created before source code is written.  A primary example of MDD is the Object Management Group (OMG)?s Model Driven Architecture (MDA) standard.   With MDD a serial approach to development is often taken, MDD is quite popular with traditionalists, although as the RUP/EUP shows it is possible to take an iterative approach with MDD.  The difference with AMDD is that instead of creating extensive models before writing source code you instead create agile models which are just barely good enough. 

Figure 1 depicts a high-level lifecycle for AMDD for the release of a system.  First, let?s start with how to read the diagram.  Each box represents a development activity.  The initial modeling activity includes two main sub-activities, initial requirements modeling and initial architecture modeling.  These are done during cycle 0, cycle being another term for iteration.  ?Cycle 0? is an XP term for the first iteration before you start into development cycles, which are iterations one and beyond (for that release).  The other activities ? model storming, reviews, and implementation ? potentially occur during any cycle, including cycle 0.   The time indicated in each box represents the length of an average session: perhaps you?ll model for a few minutes then code for several hours.   I?ll discuss timing issues in more detail below.

阅读全文...

My previous two articles in this series have provided a general overview of the Java 2 Platform, Enterprise Edition (J2EE) and a more detailed look at the technologies contained within the web-tier of the J2EE platform. Using these technologies allows us to build scalable web-based interfaces for our applications but one question still remains. Where should the business logic reside? This is the subject of this article.

阅读全文...

Summary
The Java 2 Enterprise Edition (J2EE) Platform is defined by four key pieces: the specification, the reference implementation, the compatibility test suite, and the BluePrints program. BluePrints describes the best practices and design guidelines for a distributed component architecture. This article introduces an eight-step J2EE development methodology based on the Rational Unified Process and the BluePrints sample application. By reading this article, you will better understand many important J2EE architecture topics, and be able to apply that knowledge to extend and modify this simple methodology to solve your special business problems. (3,600 words; September 28, 2001)

阅读全文...