Pour 2 tablespoons oil around top of preheated wok (or in a large skillet), coating sides; heat at medium-high (375 degrees F) for 2 minutes. Add carrot and next 3 ingredients; stir-fry 3 to 5 minutes or until crisp-tender. Stir in juice mixture. Bring to a boil and boil 1 minute. Stir in cornstarch mixture, cook, stirring constantly, until thickened. Add pork and pineapple; stir-fry until thoroughly heated. Serve over rice.