Play! framework uses a <lot> of statics

java static playframework playframework-1.x
Saew picture Saew · Mar 4, 2011 · Viewed 15k times · Source

Waaah, the Play! framework has so many static methods. Where I go to school, we were told never ever to use any statics, yet Play! uses it like there's no tomorrow. Is that somehow okay? If so, why?

We (7 people and I) are planning to use the Play! framework for a project involving a web app. We decided to do it with Play! because it looks quite fun to do, all of us already know Java and the assignment is pretty hard so we wanted to focus on the actual assignment rather than also learning how to program in a different language.

We were always told, however, NEVER EVER to use 'static's in any Java program we developed, but when I look at Play! ... Well... about half the methods are static. </exaggeration>

I suppose, at the very least, we could use singleton objects (by using Scala, for example ^^) in order to program our project, but I'm quite concerned at how many statics there actually are in framework itself.

So, should I be concerned about this? Did the way the Play! developers programmed it make it so that all these statics don't pose a problem?

(For example, this thread has a rant about why static members should be avoided at all costs.)

Answer

Guillaume Bort picture Guillaume Bort · Mar 4, 2011

Play uses static methods only when it makes sense:

  • in the controller layer, because controllers are not object oriented. Controllers act as mapper between the HTTP world (that is stateless, and request/response based) and the Model layer that is fully object oriented.
  • in the model layer for factory methods, like findAll(), count(), create() which of course don't depend of any particular instances
  • in some play.libs.* classes that provides purely utility functions

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