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So let's look at the object-oriented analysis in a

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little more detail. As I said earlier, traditional analysis

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and design techniques were functionally oriented. What that means

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is that they concentrated on the functions to be performed,

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whereas the data upon which the functions operated were

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secondary to the functions themselves. Conversely, object oriented analysis, is

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primarily concerned that with a data objects, so we

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went from a functional oriented view to a data oriented

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view, what that means is that during the analysis phase,

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we define a system first in terms of the data

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types and their relationships, and the functions or methods are

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defined only later and associated with specific objects which are sets

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of data. So let's see how we can perform object

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orientated analysis in practice, so the basic idea is to be

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focused on the objects of the real world. So to

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go from a real world objects to a set of requirements.

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And we can describe this as a four-step process. The first

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step is to obtain or prepare a textual description of the

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problem to be solved. So obviously, we need to start from

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some description of the system that we need to build. And

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this is a very practical oriented approach, so that the next

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thing we do is that we take the description and we

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underline nouns. In this description. And the nouns that we underline

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will become classes in my analysis. We then look at adjectives in

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the document. We underline those, and we use that

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information to identify the attributes of the classes that we've

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previously identified. At this point we focus on active

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verbs in the description, and the analysis of the active

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verbs will give us the operations that we'll need

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to define for our classes. So, again, underline nouns, and

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those will become the classes in my system. Then,

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objectives. And, those will be the attributes of the classes.

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And, finally, active verbs that will become the operations of my classes. And

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of course, this is a high level view to take this with a

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grain of salt. But we will see that it's a very good pragmatic

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approach to identifying requirements, starting from a

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description of the system to be built.