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From: Sebastian Ewert on 22 Jul 2010 04:49
Hi,

I'm developing an joomla component and my helper an user classes are
crowing bigger and bigger. The helper class is for static use only.

Does class size decrease performance of my php scripts, even for static
usage?
Is there a general rule when to split a class to keep performance up?

Thanks for reply,
Sebastian

From: Ashley Sheridan on 22 Jul 2010 05:40
On Thu, 2010-07-22 at 10:49 +0200, Sebastian Ewert wrote:

> Hi,
>
> I'm developing an joomla component and my helper an user classes are
> crowing bigger and bigger. The helper class is for static use only.
>
> Does class size decrease performance of my php scripts, even for static
> usage?
> Is there a general rule when to split a class to keep performance up?
>
> Thanks for reply,
> Sebastian
>
>


How big roughly are we talking here? The larger a script or class is,
the more memory this uses per instance. Out of the box, PHP doesn't have
a way to share the memory space of libraries and classes, so creating
massive scripts for a website is not a great idea.

The typical approach is to break classes down into blocks such that you
need only include per script what you actually need to run that script.

For example, having a full class dedicated to user management would need
somewhere to create a list of users. Now it doesn't make sense to
include this user management class each time you want to create a list
of users, so you could split that method off into a different class
where it can easily be shared without every script loading in lots of
unnecessary code.

That's a very simple example, but it can help beforehand if you sketch
out exactly what you need to do, and then break it down into logical
classes like that. Maybe look at some UML software to help you with
this?

Thanks,
Ash
http://www.ashleysheridan.co.uk


From: Sebastian Ewert on 22 Jul 2010 06:35
Ashley Sheridan wrote:
> On Thu, 2010-07-22 at 10:49 +0200, Sebastian Ewert wrote:
>
>> Hi,
>>
>> I'm developing an joomla component and my helper an user classes are
>> crowing bigger and bigger. The helper class is for static use only.
>>
>> Does class size decrease performance of my php scripts, even for static
>> usage?
>> Is there a general rule when to split a class to keep performance up?
>>
>> Thanks for reply,
>> Sebastian
>>
>>
>
>
> How big roughly are we talking here? The larger a script or class is,
> the more memory this uses per instance. Out of the box, PHP doesn't have
> a way to share the memory space of libraries and classes, so creating
> massive scripts for a website is not a great idea.
>

The user object contains 850 Lines and about 50 functions. It also
implements 2 table-objects (DB Tables).
The helper class contains 500 Lines.

> The typical approach is to break classes down into blocks such that you
> need only include per script what you actually need to run that script.
>
> For example, having a full class dedicated to user management would need
> somewhere to create a list of users. Now it doesn't make sense to
> include this user management class each time you want to create a list
> of users, so you could split that method off into a different class
> where it can easily be shared without every script loading in lots of
> unnecessary code.

Thats exacty the point. In my user class I have functions whitch return
object-lists of diffrent users or strings with html-form elements for
managing this user account.

But if I put all these in a helper class I would anyway need to
implement the user object there, because of the other getter functions
(getUserName etc.) and the table-objects.

I always thought this would be less effective, because I have more
instances of objects.

Thanks,
Sebastian


From: "Jay Blanchard" on 22 Jul 2010 08:32
[snip]
Thats exacty the point. In my user class I have functions whitch return
object-lists of diffrent users or strings with html-form elements for
managing this user account.

But if I put all these in a helper class I would anyway need to
implement the user object there, because of the other getter functions
(getUserName etc.) and the table-objects.

I always thought this would be less effective, because I have more
instances of objects.
[/snip]

Sounds like a major refactoring is in order, how reusable is your class?

There is not enough room in this e-mail to cover the basic and
intermediate practices of OO design but it sounds like you may need to
re-think your design. Does this class do one thing and only one thing?
Does it do it really well?

Just from what I am reading I see that we have a user class
(getUserName) and that class returns lists of users? It sounds as if to
me that the user class talks not only about a single user, but perhaps
all of the users (object lists of different users).

On the surface that sounds like to classes to me, a user class and a
class to manipulate said users.


From: Sebastian Ewert on 22 Jul 2010 09:27
Jay Blanchard wrote:
> [snip]
> Thats exacty the point. In my user class I have functions whitch return
> object-lists of diffrent users or strings with html-form elements for
> managing this user account.
>
> But if I put all these in a helper class I would anyway need to
> implement the user object there, because of the other getter functions
> (getUserName etc.) and the table-objects.
>
> I always thought this would be less effective, because I have more
> instances of objects.
> [/snip]
>
> Sounds like a major refactoring is in order, how reusable is your class?
>
> There is not enough room in this e-mail to cover the basic and
> intermediate practices of OO design but it sounds like you may need to
> re-think your design. Does this class do one thing and only one thing?
> Does it do it really well?
>

Thanks for your advice. I know that I have to go much deeper into
programm design. I would appreciate if you could send me some links with
practial examples. I've only read some theoretical and very general
stuff about it and cannot link everything to the real world.

> Just from what I am reading I see that we have a user class
> (getUserName) and that class returns lists of users? It sounds as if to
> me that the user class talks not only about a single user, but perhaps
> all of the users (object lists of different users).
>

That was just to generalize things. My user class only returns
informations for one user. These informations are values of db-fields or
generated html strings.

But other classes like my message class have functions that return lists
of instances of their own class. From what you've written I think its
better to extract these functions into helper classes.

But if you want to get all messages that refer to one specific msg its
better to leave that function in the message class, isn't it? Or if you
want to get a list with all friends of a specific user?(friends are not
implemented yet)

> On the surface that sounds like to classes to me, a user class and a
> class to manipulate said users.
>
>

But back to my first Problem:

Is a class with 850 lines to long?
If it is should I take all the html genarating functions and put them in
a helper class?
If I do so and there is no way to call those functions without
initalizing the main user object, will there still be an increase of
performance?

Thanks,
Sebastian

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