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From Analysis to Design - Overview


The task of moving from the analysis model of a system to a design of the system is a creative step that involves many design decisions to be taken. The reason is that the purpose of the analysis model is to give an abstract understanding of the system to be built, and an understanding of the concepts that are needed in order to describe a solution of the problem the system is to solve. The purpose of the analysis model is not to give a precise definition of how the problem is to be solved or to decide how the architecture and reuse issues are taken care of. These aspects are the purpose of the design activities. Both the system design and the object design are focussed on these type of questions that are necessary to solve in an efficient way in a development project.

The SOMT method introduces a specific concept to emphasize the task of moving from one model to another. It is particularly useful when moving from the analysis model, with its abstract view of the problem, to the design model, with its constructive precise definition of the system that solves the problem. This is the Paste As concept that was introduced in Implinks and the Paste As Concept.

During design the idea is to encapsulate the creative design action taken when moving from the analysis model to the design model into one visible action. From a pragmatic point of view the designer just takes an analysis object and pastes it as a design object. However by doing this simple action the designer documents a number of the design decisions that are involved in the design activity.

Figure 654 : The Paste As concept

One important aspect of the paste-as concept is the relation to traceability links between different models. When performing the paste-as action the designer not only creates design objects. He also creates a link between the analysis object and the design objects. This link defines in a precise and compact way the design decisions taken. The links are a vital part of the project documentation that is automatically created by the tools. The links can be inspected when understanding the system and can be used for a number of purposes, e.g.:


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