Too many objects?

skalrynd

I'm working on a project that could require a massive OO structure... possibly hundreds of classes under a root class. With my current approach, all of these classes would be loaded upon just about every request. Any suggestions? How much lag on a server would that cause with such a script being included on most requests?

Should I "chop it up"? Not all classes are needed every time. Just the related class as well as all of its parents (obviously). But how would you go about doing that?

The site is PHP and MySQL driven. I've considered "indexing" classes and having them placed in shorter files, then just pull include files from the DB. That's a lot of coding and would it just be faster to just load all objects instead? Where's the threshold (in size of file holding classes) with that type of procedure?

Any suggested articles for structuring large OO in a scripting language? :o

matto

I made this experience with PHP 4, perhaps it's of use to you.

I needed to implement a calories calculator and had the idea to instantiate about 300 mini-objects for each type of food in the database.
although those objects ware hardly more than data structures / containers (ID, name, calories) they filled up the available memory very fast.

so I came to proceed like this:

if the (many) objects could be replaced by something less storage consuming, like an array structure, it's the better choice.
instead of preloading everything, you could load information from db as well as create objects only when requested ("get" function:
```
if(empty($this->typeXObjects)) $this->loadTypeXObjectsFromDb();
```
) - think about a cache.
if you are trying to code exclusively OO, as required in Java, consider this: for typically sequential tasks (such as list generation from db queries) you don't have a choice in Java other than to code everything entirely oo. In php however you do have a choice. from my experience, the best practice is to find a good balance between oo and sequential parts in order to optimize performance and/or code maintainability/readability.

hope these thoughts are useful.

planetsim

Should I "chop it up"? Not all classes are needed every time. Just the related class as well as all of its parents (obviously). But how would you go about doing that?

Of course the way you would do this is have each class in a seperate file a good way to sort through the many files is to give the class name on the file e.g.

class myClass {
}

Would be saved as myClass.php it is a good habit to get into. You should also use [man]include_once[/man] and/or [man]require_once[/man] so you dont load the same file twice.

Going a little side tracked, why do you think you need to load some many classes? What will these classes do? PHP should be able to handle it all however if your on a shared host you will notice considerable latency in script execution depending on how many and how they are designed.