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|
--TEST--
ZE2 Late Static Binding and Singleton
--FILE--
<?php
abstract class Singleton
{
static private $instances = array();
static private $nextInstanceId = 0;
private $instanceId = NULL;
static final public function getInstance()
{
$caller = get_called_class();
if (!isset(self::$instances[$caller])) {
self::$instances[$caller] = new $caller;
self::$instances[$caller]->instanceId = self::$nextInstanceId++;
}
return self::$instances[$caller];
}
public final function getInstanceId()
{
return $this->instanceId;
}
public final function identify()
{
var_dump($this);
}
}
class Foo extends Singleton {
}
class Bar extends Singleton {
}
class Baz extends Bar {
}
$u = Foo::getInstance();
$v = Bar::getInstance();
$w = Baz::getInstance();
$u->identify();
$v->identify();
$w->identify();
$x = Foo::getInstance();
$y = Bar::getInstance();
$z = Baz::getInstance();
$u->identify();
$v->identify();
$w->identify();
$x->identify();
$y->identify();
$z->identify();
?>
===DONE===
--EXPECTF--
object(Foo)#%d (1) {
["instanceId":"Singleton":private]=>
int(0)
}
object(Bar)#%d (1) {
["instanceId":"Singleton":private]=>
int(1)
}
object(Baz)#%d (1) {
["instanceId":"Singleton":private]=>
int(2)
}
object(Foo)#%d (1) {
["instanceId":"Singleton":private]=>
int(0)
}
object(Bar)#%d (1) {
["instanceId":"Singleton":private]=>
int(1)
}
object(Baz)#%d (1) {
["instanceId":"Singleton":private]=>
int(2)
}
object(Foo)#%d (1) {
["instanceId":"Singleton":private]=>
int(0)
}
object(Bar)#%d (1) {
["instanceId":"Singleton":private]=>
int(1)
}
object(Baz)#%d (1) {
["instanceId":"Singleton":private]=>
int(2)
}
===DONE===
|
