xref: /PHP-8.1/Zend/tests/lsb_018.phpt (revision f8d79582) 
1--TEST--
2ZE2 Late Static Binding and Singleton
3--FILE--
4<?php
5abstract class Singleton
6{
7    static private $instances = array();
8    static private $nextInstanceId = 0;
9    private $instanceId = NULL;
10    static final public function getInstance()
11    {
12        $caller = get_called_class();
13        if (!isset(self::$instances[$caller])) {
14            self::$instances[$caller] = new $caller;
15            self::$instances[$caller]->instanceId = self::$nextInstanceId++;
16        }
17        return self::$instances[$caller];
18    }
19    public final function getInstanceId()
20    {
21        return $this->instanceId;
22    }
23    public final function identify()
24    {
25        var_dump($this);
26    }
27}
28
29class Foo extends Singleton {
30}
31
32class Bar extends Singleton {
33}
34
35class Baz extends Bar {
36}
37
38$u = Foo::getInstance();
39$v = Bar::getInstance();
40$w = Baz::getInstance();
41
42$u->identify();
43$v->identify();
44$w->identify();
45
46$x = Foo::getInstance();
47$y = Bar::getInstance();
48$z = Baz::getInstance();
49
50$u->identify();
51$v->identify();
52$w->identify();
53$x->identify();
54$y->identify();
55$z->identify();
56?>
57--EXPECTF--
58object(Foo)#%d (1) {
59  ["instanceId":"Singleton":private]=>
60  int(0)
61}
62object(Bar)#%d (1) {
63  ["instanceId":"Singleton":private]=>
64  int(1)
65}
66object(Baz)#%d (1) {
67  ["instanceId":"Singleton":private]=>
68  int(2)
69}
70object(Foo)#%d (1) {
71  ["instanceId":"Singleton":private]=>
72  int(0)
73}
74object(Bar)#%d (1) {
75  ["instanceId":"Singleton":private]=>
76  int(1)
77}
78object(Baz)#%d (1) {
79  ["instanceId":"Singleton":private]=>
80  int(2)
81}
82object(Foo)#%d (1) {
83  ["instanceId":"Singleton":private]=>
84  int(0)
85}
86object(Bar)#%d (1) {
87  ["instanceId":"Singleton":private]=>
88  int(1)
89}
90object(Baz)#%d (1) {
91  ["instanceId":"Singleton":private]=>
92  int(2)
93}
94