In php, the class name::class, what does it mean?

Question

Excuse me: In the following PHP code, what does the class name::class mean?

protected $apiClass = [
    AccessToken::class,
    JsCodeToSession::class,
    CreateQrCode::class,
];

Answer 1

Class name with namespace

Answer 2

Contains fully qualified name

<?php
namespace NS {
    class ClassName {
    }
    
    echo ClassName::class;  //输出NS\ClassName
}
?>

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