不使用setter和getter真是错吗？

Question

I'm kind of new in PHP. For some reason in other types of programming languages like JAVA I have no problem with using setters and getters for every single variable, but when I'm programming in PHP probably because it is so flexible it feels kind of like a waste of time. It feels simpler to just set the class attributes as public most of the time and manipulating them like that. The thing is that when I do it like this I feel like I'm doing something wrong and going against OO principles.

Is it really that wrong not using setters and getters? Why or why not? How do you guys do it most of the time?

Answer 1

The main problem with not using property accessors is that if you find out you ever need to change a field to a property later on – to make it a computed property in a subclass, for instance – you’ll break clients of your API. For a published library, this would be unacceptable; for an internal one, just quite a lot of work fixing things.

For private code or small apps, it could be feasible to just wing it. An IDE (or text editor) will let you generate accessor boilerplate and hide it using code folding. This arguably makes using getters and setters mechanically fairly easy.

Note that some programming languages have features to synthesise the default field+getter+setter – Ruby does it via metaprogramming, C# has auto-implemented properties. And Python sidesteps the issue completely by letting you override attribute access, letting you encapsulate the attribute in the subclass that needs it instead of having to bother with it up front. (This is the approach I like best.)