.
namespace core_cache;
use core\exception\coding_exception;
use ArrayObject;
/**
* An array of cacheable objects.
*
* This class allows a developer to create an array of cacheable objects and store that.
* The cache API doesn't check items within an array to see whether they are cacheable. Such a check would be very costly to both
* arrays using cacheable object and those that don't.
* Instead the developer must explicitly use a cacheable_object_array instance.
*
* The following is one example of how this class can be used.
*
* $data = array();
* $data[] = new cacheable_object('one');
* $data[] = new cacheable_object('two');
* $data[] = new cacheable_object('three');
* $cache->set(new cacheable_object_array($data));
*
* Another example would be
*
* $data = new cacheable_object_array();
* $data[] = new cacheable_object('one');
* $data[] = new cacheable_object('two');
* $data[] = new cacheable_object('three');
* $cache->set($data);
*
*
* @copyright 2012 Sam Hemelryk
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
* @package core_cache
*/
class cacheable_object_array extends ArrayObject implements cacheable_object_interface {
/**
* Constructs a new array object instance.
* @param array $items
*/
final public function __construct(array $items = []) {
parent::__construct($items, ArrayObject::STD_PROP_LIST);
}
/**
* Returns the data to cache for this object.
*
* @return cached_object[] An array of cached_object instances.
* @throws coding_exception
*/
final public function prepare_to_cache() {
$result = [];
foreach ($this as $key => $value) {
if ($value instanceof cacheable_object_interface) {
$value = new cached_object($value);
} else {
throw new coding_exception('Only cacheable_object instances can be added to a cacheable_array');
}
$result[$key] = $value;
}
return $result;
}
/**
* Returns the cacheable_object_array that was originally sent to the cache.
*
* @param array $data
* @return self
* @throws coding_exception
*/
final public static function wake_from_cache($data) {
if (!is_array($data)) {
throw new coding_exception('Invalid data type when reviving cacheable_array data');
}
$result = [];
foreach ($data as $key => $value) {
$result[$key] = $value->restore_object();
}
$class = __CLASS__;
return new $class($result);
}
}
// Alias this class to the old name.
// This file will be autoloaded by the legacyclasses autoload system.
// In future all uses of this class will be corrected and the legacy references will be removed.
class_alias(cacheable_object_array::class, \cacheable_object_array::class);