Concept: Abstract Away Complexity |
Relationships
Related Elements | Design Component Architecture
Main Description
Software development is a pursuit characterized by complexity. This can take many forms, for example, accommodating complex requirements, technology or team dynamics. Being able to elevate the level of abstraction helps us manage this complexity and make tractible progress in the face of an inherently difficult task. There are a number of strategies available to help abstract away complexity. Here are some suggestions. #### Leverage Patterns Patterns help us take advantage of proven techniques for solving common problems. We can benefit from the experience of seasoned practioners and avoid "re-inventing the wheel." The use of patterns is a crucial aspect of an architecture-centric approach to development, helping to reduce the novelty and diversity of a solution and thereby improving quality. See Patterns for more information. #### Architect with Components and Services This strategy helps manage software complexity through partioning a system into a set of loosely-coupled and highly-cohesive subsystem. This approach has a number of benefits, including the ability to organise the team around a set of smaller, more manageable objectives; and the ability to subsitute parts of the system without disturbing the overall cohesion of the system. Exposing services encourages re-use thorough making the functionality of the system easier to comprehend. Focusing on services makes it possible to understand what the system does from a technical perspective without having to necessarily understand the details of how the system works. See Component for more information. #### Actively Promote Reuse Incorporating existing software into an overall architecture helps to reduce cost and improve quality by reusing proven working software rather than developing from scratch. It also helps to reduce the burden of maintenance by eliminating duplication in the software estate. Although often difficult to manage, a well-executed re-use strategy can reap signifcant benefits for a project and/or enterprise. #### Model Key Perspectives Modeling helps to raise the level of abstraction by simplifying complex ideas into pictures. Good models are able to convey information that helps the team visualize, specify, construct and document software. The Unified Modeling Language provides an industry standard approach to software modeling that is widely used across the industry. When applying this strategy, a number of techniques can be employed. Identify the key perspectives - Focus on modeling the things that count. Few (if any) projects benefit from modeling the entire design to an excrutiating level of detail. Make sure that you understand why you are modeling something and who will benefit from it. Sketch the design - Not all models need to be detailed, complete and presented in a software modeling tool. It is often perfectly acceptable (if not desirable) to produce hand-drawn sketches on paper or around a whiteboard when exploring and communicating the architecture and design with your team. You can use a digital camera or electronic whiteboard to capture these diagrams and share them. For many small projects, this is often all you need. See www.agilemodeling.com for more information. Agree on a standard notation - In a team environment it is naturally important that others can understand your diagrams without too much explanation. Choosing a standard notation will enable others to quickly comprehend your diagrams without ambiguity. The Unified Modeling Language is an example of a widely understood notation. Visualize the code - Many software development tools allow you to view the code as models, making it easier to comprehend static and dynamic aspects of a complex code base. Document key architectural perspectives - Even if you choose to model very little your design, it is often advantageous to produce diagrams communicating the key architectural aspects of the system. Conveying the "big picture" to the rest of the team will help them understand the overall approach and develop cohesive software. Use a Model-Driven Development approach - This approach takes formal and complete models and applies a series of defined transformations, ultimately resulting in the generation of working software. This technique offers a number of benefits, with reported success stories. See www.omg.org/mda for more information.
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