[Tutor] impact of OO

[Cameron Stoner]

Hi all,

I saw this post on the wire and wanted to ask how you know what should have
the behavior and how to organize the program.  I am making a simple message
encryption program and wanted to see if implementing OOP practices would be
difficult or not.  It is not a small program at all.  By the time it will be
done it will be a couple thousand lines at least.  I will add the GUI part
to the program later, but for now it is text based.  Is there any place I
could just learn about UML?

> > I have a general question about Object Oriented programming
> > in general:  why is it so lauded by... well, by everyone?
>
> Its not. There are several minority groups who believe that
> OO is a retrograde step. Others believe that things like
> Functional Programming are more important etc etc. But
> the general opinion is that OO is a big improvement on
> traditional "Structured Methods"
>
>
> There are lots of reasons, most only relevant to large
> projects so its hard for the newbie writing programs of
> only a few hundred lines to see the avantages. But one
> your prohgrams get into the tens of thousands of lines
> the benefits become far more obvious. However...
>
> > to with a group of variable names.  It's hard to describe, but this
> > makes it much easier --
>
> ... even in smaller projects it can show benefits in ease
> of comprehension - as you've seen.
>
> > but it is far more organized and cleaner.
>
> We used to have one maintenance programmer looking after,
> on average 20,000 lines of code(in C) when we moved to
> OO designs we have one programmer looking after 100,000
> lines. A 5 to 1 improvement, mainly due to the better
> cohesion of the designs using OOP.
>
> > ...but I still don't really see how
> > it's that big a deal -- it's simply a different way of
> > organizing code, as far as I can tell.
>
> Which is the hardest aspect of industrial grade
> software engineering. Organizing code such that when one
> bit changes you don't need to change everything elsder
> with it has been the biggest headache in softwae since
> the start of commercial programming. OOP helps do just that.
>
> > Please prove me wrong and help me see how OO "changed everything".
>
> It doesn't change everything but it helps a lot.
>
> There are other aspects to OOP too that we haven't
> touched on. The ease of extending existing code without
> changing it (and thus breaking existing code relying
> on the bit being extended) via inheritance. The way
> OOP eliminates long if/elif/else chains (or switch
> statements)via polymorphism (see the OOP page in my
> tutor for a discussion of polymorphism and inheritance)
>
> The ability to build whoile abstract frameworks which
> act as application templates. These can quickly be
> added to to produce new apps - most GUI frameworks
> are done this way.
>
>
> > PS:  Also, I have heard someone say that "in Java everything is an
> > object".
>
> Its a lie. In Java everything is in a class...
> only some things are objects. There is a big difference
> which the Java community seems to disregard. But claiming
> that everything is anobject is a big marketing coup!
>
>
> > Java, especially since there are many employers
>
> This sadly is true. Mainly a result of the "emperors new clothes" syndrome
> but none the less Java is taking over.
>
>
> in my area (Boston)
> > advertising an interest in Java programmers (and I will be
> > out of a job
> > as soon as my project is finished).  Sadly, much more than Python or
> > PHP.  But it seems like a big language to learn.
> >
> >
> >
> >
> >
> >
>
>
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