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Now that we identify the classes in my system,
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let's see how we can identify the attributes for
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these classes. First of all let's recall what attributes
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are. Attributes represent the structure of a class the individual
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data items that compose the state of the class.
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So how do we identify these attributes? Attributes may be
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found in one of three ways. By examining class
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definitions, by studying the requirements, and by applying domain knowledge.
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And notice that I want to stress, that this is always
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a very important aspect. No matter what kind of system you're
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developing. Domain knowledge tends to be fairly important to identify things
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Which might not be provided in the descriptions of the system
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that tend to be incomplete. And that you can derive by
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the fact that you are familiar with the domain. So always
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keep in mind the domain knowledge is important for analysis, for
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design, for requirements gathering and so on. So now let's go
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back to our description of the system. As I said,
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I will bring you back for each step of our
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analysis. And in this case, we're going to focus on
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course offering. And we can say that the course offering, according
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to the description, has a number, a location, and a
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time. So this is a pretty clear indication that these are
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important aspects of the course offering. So they probably should
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become attributes of the course offering class. So now if we
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report here that sentence, and once more, we underline
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the information that we underlined in the description. We can
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clearly see how this can be mapped into the definition
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of the class. So our class course offering after this
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step the analysis will have 3 attributes: number, location, and
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time. And as you can see here, I'm not specifying
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the type or any other additional information. So in this
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first step I'm just interested in having a first draft.
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of the class diagram, that I can then
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refine in the next iterations of my analysis.
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