1: <?php
  2: /**
  3:  * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
  4:  * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
  5:  *
  6:  * Licensed under The MIT License
  7:  * For full copyright and license information, please see the LICENSE.txt
  8:  * Redistributions of files must retain the above copyright notice.
  9:  *
 10:  * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
 11:  * @link          https://cakephp.org CakePHP(tm) Project
 12:  * @since         3.0.0
 13:  * @license       https://opensource.org/licenses/mit-license.php MIT License
 14:  */
 15: namespace Cake\Collection;
 16: 
 17: use ArrayIterator;
 18: use InvalidArgumentException;
 19: use IteratorIterator;
 20: use Serializable;
 21: use Traversable;
 22: 
 23: /**
 24:  * A collection is an immutable list of elements with a handful of functions to
 25:  * iterate, group, transform and extract information from it.
 26:  */
 27: class Collection extends IteratorIterator implements CollectionInterface, Serializable
 28: {
 29: 
 30:     use CollectionTrait;
 31: 
 32:     /**
 33:      * Constructor. You can provide an array or any traversable object
 34:      *
 35:      * @param array|\Traversable $items Items.
 36:      * @throws \InvalidArgumentException If passed incorrect type for items.
 37:      */
 38:     public function __construct($items)
 39:     {
 40:         if (is_array($items)) {
 41:             $items = new ArrayIterator($items);
 42:         }
 43: 
 44:         if (!($items instanceof Traversable)) {
 45:             $msg = 'Only an array or \Traversable is allowed for Collection';
 46:             throw new InvalidArgumentException($msg);
 47:         }
 48: 
 49:         parent::__construct($items);
 50:     }
 51: 
 52:     /**
 53:      * Returns a string representation of this object that can be used
 54:      * to reconstruct it
 55:      *
 56:      * @return string
 57:      */
 58:     public function serialize()
 59:     {
 60:         return serialize($this->buffered());
 61:     }
 62: 
 63:     /**
 64:      * Unserializes the passed string and rebuilds the Collection instance
 65:      *
 66:      * @param string $collection The serialized collection
 67:      * @return void
 68:      */
 69:     public function unserialize($collection)
 70:     {
 71:         $this->__construct(unserialize($collection));
 72:     }
 73: 
 74:     /**
 75:      * {@inheritDoc}
 76:      *
 77:      * @return int
 78:      */
 79:     public function count()
 80:     {
 81:         $traversable = $this->optimizeUnwrap();
 82: 
 83:         if (is_array($traversable)) {
 84:             return count($traversable);
 85:         }
 86: 
 87:         return iterator_count($traversable);
 88:     }
 89: 
 90:     /**
 91:      * {@inheritDoc}
 92:      *
 93:      * @return int
 94:      */
 95:     public function countKeys()
 96:     {
 97:         return count($this->toArray());
 98:     }
 99: 
100:     /**
101:      * Returns an array that can be used to describe the internal state of this
102:      * object.
103:      *
104:      * @return array
105:      */
106:     public function __debugInfo()
107:     {
108:         return [
109:             'count' => $this->count(),
110:         ];
111:     }
112: }
113: