At this point, it’s doubtful that any of us will confuse modularity with service oriented architecture (SOA). The two appear to be distinctly different beasts. Yet, they are very similar in nature and each offers tremendous benefit to organizations. At one level, the principles behind service design apply equally to module design. Like we try [...]
Thus far, we’ve spent the majority of Part 1 making the case for modularity. Before we delve too deeply into the patterns, let’s witness first-hand the benefits of a modular architecture.
8.1 – Why No OSGi?
The example that follows doesn’t use OSGi. One would think that if I’m going to modularize my system, I’d want to [...]
Reuse is software development’s unattainable panacea. The ability to compose systems from reusable elements has long been our achille’s heel. We want reuse so badly, yet our failures are spectacular. Almost all major technology trends of the past 20 years touts reuse as the saving grace. Vendors have sold billions of dollars in software through [...]
Modularity is not a new concept. In his 1972 paper titled, “On the Criteria to be used in Decomposing Systems Into Modules”, David Parnas cited the work of Gouthier and Pont as the first lucid statement of modular programming:
A well-defined segmentation of the project effort ensures system modularity. Each task forms a separate, distinct program [...]
Modularity plays an important role in software architecture. It fills a gap that has existed since we began develop enterprise software systems in Java. Here, we’ll discuss that gap and explore how modularity is an important intermediary technology that fills the gap.
4.1 – Defining Architecture
There are numerous definitions of architecture. But within each lies a [...]
There are two aspects to modularity – the runtime model and the development model. Today, emphasis is on the runtime model, with frameworks emerging that provide runtime support for modularity. But eventually, as the runtime model gains adoption, the importance of the development model will take center stage. The patterns in this book focus on [...]
In 1995, design patterns were all the rage. Today, I find the exact opposite. Patterns have become commonplace, and most developers use patterns on a daily basis without giving it much thought. New patterns rarely emerge today that have the same impact of the GOF patterns. In fact, the industry has largely moved past the [...]
Before we get started, we need to answer a rather simple question. What is a software module?
2.1 – Defining a Module
I’d like to say that a module is simply a “chunk of software.” Unfortunately, that doesn’t offer enough concision to differentiate a module from other software chunks, like objects, packages, services, or even applications. So [...]