1: <?php
 2: 
 3: namespace Liberty;
 4: 
 5: 
 6: /**
 7:  * Collection class.
 8:  *
 9:  * @category  Cryptocurrency
10:  * @package   Liberty
11:  * @license   https://en.wikipedia.org/wiki/Public_domain Public Domain.
12:  * @version   1.0.0
13:  * @since     2018-02-17
14:  * @author    Alireza Rahmani Khalili @alirezarahmani, Liberty Group <cryptolibertygroup@gmail.com>
15:  */
16: 
17: 
18: 
19: class Collection {
20: 
21:     /**
22:      * The List itself
23:      * @var string
24:      */
25:     protected $items = array();
26: 
27: 
28: 
29:     public function __construct($list=array())
30:     {
31:         if(isset($list)) {
32:             $this->items = $list;
33:         }
34:     }
35: 
36: 
37: 
38:     public function add($obj, $key = null) {
39:         if ($key == null) {
40:             $this->items[] = $obj;
41:         }
42:         else {
43:             if (isset($this->items[$key])) {
44:                 throw new KeyHasUseException("Key $key already in use.");
45:             }
46:             else {
47:                 $this->items[$key] = $obj;
48:             }
49:         }
50:     }
51: 
52: 
53: 
54:     public function remove($key) {
55:         if (isset($this->items[$key])) {
56:             unset($this->items[$key]);
57:         }
58:         else {
59:             throw new KeyInvalidException("Invalid key $key.");
60:         }
61:     }
62: 
63: 
64: 
65:     public function item($key){
66:         if (isset($this->items[$key])) {
67:             return $this->items[$key];
68:         }
69:         else {
70:             throw new KeyInvalidException("Invalid key $key.");
71:         }
72:     }
73: 
74: 
75:     public function items() {
76:         return $this->items;
77:     }
78: 
79: 
80:     public function keys() {
81:         return array_keys($this->items);
82:     }
83: 
84: 
85: 
86:     public function length() {
87:         return count($this->items);
88:     }
89: 
90: 
91: }
92: 
93: 
94: ?>
95: