call public method after static method in php

Question

I have class sample and first call static method and return to call other public method:

class foo{
 public static $var;
    public static function first()
    {
       self::$var = 1;
       return self::class;
    }  
    public function second()
    {
       return self::$var;
    }
}

and I need call public method after static method sample here:

foo::first()->second();

Answer 1

No, you can't do that, because from your static method you return just the string - class name. For calling your public method, you need that static method is returning an instance of your object, like this

return new self();