<?php
class Singleton {
private static $instanciated = false;
public function __construct()
{
if (self::$instanciated === true) {
throw new RuntimeException('Could not instanciate class');
}
self::$instanciated = true;
}
private $var;
public function get(): int {
return $this->var;
}
public function set(int $value) {
$this->var = $value;
}
}
class Factory {
private $instance = null;
public function getInstance()
{
if ($this->instance === null) {
$this->instance = new Singleton();
}
return $this->instance;
}
}
$factory = new Factory();
$o = $factory->getInstance();
$o->set(5);
$factory2 = new Factory();
$o2 = $factory2->getInstance();
var_dump($o2->get());
Fatal error: Uncaught RuntimeException: Could not instanciate class in /in/Z43OI:9
Stack trace:
#0 /in/Z43OI(32): Singleton->__construct()
#1 /in/Z43OI(43): Factory->getInstance()
#2 {main}
thrown in /in/Z43OI on line 9
Process exited with code 255.