Is it ok to declare destructor as private?

Question

Some of my classes declare their constructors as private because an object of such class is only allowed to be created by a static method of the class. May I also declare destructors of such classes as private to keep it symmetric, is it safe?

EDIT: Ok, seems like this is simply not possible:

Fatal error: Call to private AClass::__destruct() from context '' in /script on line 0

(the context is empty and there's no such thing as line 0). For some reason I used to think that the PHP runtime is almighty and can destruct anything it wants.

Answer 1

In php the __destruct magic method must be public. The method will automatically be called externally to the instance. Declaring __destruct as protected or private will result in a warning and the magic method will not be called.

There's no symmetry necessary, as you should never explicitly call __destruct.

Answer 2

Seems that you are implementing the singleton pattern. In this pattern constructor must be private and you have a static method that returns an instance of the class. If there's no instance, this static method will create it and return it.

If you set destructor access to private, you don't allow to other classes or functions to destruct that instance and this could be inconsistent if in a point of execution of your application you will not use that instance any more. There's no reason to set destructor to private because even if it's public, the static method is capable to return a new instance if there's no one.