I wonder when should we use getter-setter methods via class's construct parameters

Question

I wonder this, when should I use getter-setter methods in a class and when should I use class's contruct parameters?

I will explain it with PHP. For example, I write a class below:

class foo{
    public $a;    //required parameter
    public $b;    //optional parameter

    public function __construct(){
        //some code
    }

    public function setA($a){
        $this->a = $a;
    }
    public function getA(){
        return $this->a;
    }
    public function setB($a){
        $this->a = $a;
    }
    public function getB(){
        return $this->a;
    }

    public function bar(){
        //do something with class attributes by using getter - setter methods.
    }
}

$foo = new foo();
$foo->setA('something');
$foo->setB('something2');
$foo->bar();

I can write a class by this way absolutely. But, I can write a class another way using construct parameters. Example below:

class foo{
    public $a;    //required parameter
    public $b;    //optional parameter

    public function __construct($a, $b){
        $this->setA($a);
        $this->setB($b);
        //some code
    }

    protected function setA($a){
        $this->a = $a;
    }
    public function getA(){
        return $this->a;
    }
    protected function setB($a){
        $this->a = $a;
    }
    public function getB(){
        return $this->a;
    }

    public function bar(){
        //do something with class attributes by using getter - setter methods.
    }
}

$foo = new foo('something', 'something2');
$foo->bar();

I think that, if I have a required parameter, I want to it on construct method. But, if I have optional parameter, I want it by the setter class. For example:

class foo{
    public $a;    //required parameter
    public $b;    //optional parameter

    public function __construct($a){
        $this->setA($a);
        //some code
    }

    protected function setA($a){
        $this->a = $a;
    }
    public function getA(){
        return $this->a;
    }
    public function setB($a){
        $this->a = $a;
    }
    public function getB(){
        return $this->a;
    }

    public function bar(){
        //do something with class attributes by using getter - setter methods.
    }
}

$foo = new foo('something');
// if I will use an optional parameter, I can set it by the setter method
$foo->setB('something2');
$foo->bar();

Well, I want to learn stg about code write methods. Which one is popular? Which one is useful, which one is true_ When I should use one of these? Thanks a lot.

Possible duplicate of [PHP Setters/Getters and Constructor](https://stackoverflow.com/questions/11740145/php-setters-getters-and-constructor) — StoYan, Oct 10 '19 at 13:44
There's no need to use setters/getters on the class `__construct`, because setters and getters are mainly meant to encapsulate the class properties to the exterior, in order to avoid direct access to the class properties. — Claudio, Oct 10 '19 at 13:53

score 0 · Answer 1 · answered Oct 10 '19 at 13:40

The "true" way to write the method and the constructor depends on what is needed at the instantiation time.

In the constructor there must be all the mandatory arguments to let the class works properly, as you said the non optional parameters.

You can also insert optional parameters in the constructor to streamline the code in the case in this phase you already know these values, by doing so you don't need to invoke its setters later.

I wonder when should we use getter-setter methods via class's construct parameters

1 Answers1