PHP \DesignPatterns\Behavioral\Command\AddMessageDateCommand \DesignPatterns\Behavioral\Command\AddMessageDateCommand \DesignPatterns\Behavioral\Command\UndoableCommand \DesignPatterns\Behavioral\Command\Command \DesignPatterns\Behavioral\Command\Invoker \DesignPatterns\Behavioral\Command\HelloCommand \DesignPatterns\Behavioral\Command\Receiver Fields Constants Constructors Methods private