解决这个问题的最好方法是不要创建那个抽象类。

不要将对象创建与业务逻辑结合在同一个类中。这称为静态链接依赖，通常是有缺陷的设计，因为您无法在运行时更改它（例如，对于测试或每个挂钩）。Avoid inheritance.

Separation of concerns 和dependency injection 将解决这个问题。

实例

interface Plugin_Setup_Interface
{
    public function activate( $network_wide );
    public function deactivate( $network_wide );
}

class Plugin_Setup implements Plugin_Setup_Interface
{

    public function activate( $network_wide ) {}

    public function deactivate( $network_wide ) {}
}

class Plugin_Starter
{
    private $plugin_file = \'\';

    private $setup = NULL;

    public function __construct(
                               $plugin_file,
        Plugin_Setup_Interface $setup = NULL
    )
    {
        $this->plugin_file = $plugin_file;
        $this->setup       = $setup;
    }

    public function init()
    {
        if ( ! is_null( $this->setup ) )
        {
            register_activation_hook(
                $this->plugin_file,
                array ( $this->setup, \'activate\' )
            );

            register_deactivation_hook(
                $this->plugin_file,
                array ( $this->setup, \'deactivate\' )
            );
        }
    }
}

// call your auto-loader, then …

$start = new Plugin_Starter( __FILE__, new Plugin_Setup() );
$start->init();