Exercises in Programming Style–Things

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Fol­low­ing on from the last post, we will look at the Things style today.

 

Style 10 – Things

You may also know this style as OOP.

 

Constraints

  • Larger problem is decomposed into things that make sense for the problem domain
  • Each thing is a capsule of data that exposes procedures to the rest of the world
  • Data is never accessed directly, only through these procedures
  • Capsules can re-appropriate procedures defined in other capsules

 

First, we have a thing for storing data from a file:

image

Then, we another thing for storing the stop words we’ll dealing with later:

image

Next, we have another thing that keeps track of the word frequencies:

image

Finally, we have a thing that controls the flow of our application:

image

And to tie everything together, we need to construct and run the controller:

image

Voila!

 

You can find the source code for this exer­cise here.

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