For example:

// Sets the public or protected $object->propertyName property
Hydrator::hydrate($object, ['propertyName' => $propertyValue]);

// Sets a private property defined on its parent Bar class:
Hydrator::hydrate($object, ["\0Bar\0privateBarProperty" => $propertyValue]);

// Alternative way to set the private $object->privateBarProperty property
Hydrator::hydrate($object, [], [
    Bar::class => ['privateBarProperty' => $propertyValue],
]);

Instances of ArrayObject, ArrayIterator and SplObjectStorage can be hydrated
by using the special "\0" property name to define their internal value:

// Hydrates an SplObjectStorage where $info1 is attached to $obj1, etc.
Hydrator::hydrate($object, ["\0" => [$obj1, $info1, $obj2, $info2...]]);

// Hydrates an ArrayObject populated with $inputArray
Hydrator::hydrate($object, ["\0" => [$inputArray]]);