Online PHP editor | output for 1de02

<?php interface GoAlgorithm { public function go(); } class GoByDrivingAlgorithm implements GoAlgorithm { public function go() { echo "Now I'm driving." .PHP_EOL; } } class GoByFlying implements GoAlgorithm { public function go() { echo "Now I'm flying." . PHP_EOL; } } class GoByFlyingFast implements GoAlgorithm { public function go() { echo "Now I'm flying fast" . PHP_EOL; } } class Vehicle { private $goAlgorithm; public function __construct(GoAlgorithm $goType = null) { $this->goAlgorithm = $goType; } public function setModeOfTransportation(GoAlgorithm $goType) { $this->goAlgorithm = $goType; } public function drive() { return $this->goAlgorithm->go(); } } // setter injection $streetRacer = new Vehicle(); $streetRacer->setModeOfTransportation(new GoByDrivingAlgorithm()); $formulaone = new Vehicle(); $formulaone->setModeOfTransportation(new GoByDrivingAlgorithm()); $helicopter = new Vehicle(); $helicopter->setModeOfTransportation(new GoByFlying()); $jets = new Vehicle(); $jets->setModeOfTransportation(new GoByFlyingFast()); $streetRacer->drive(); $formulaone->drive(); $helicopter->drive(); $jets->drive(); // constructor injection $streetRacerByCtor = new Vehicle(new GoByDrivingAlgorithm()); $formulaoneByCtor = new Vehicle(new GoByDrivingAlgorithm()); $helicopterByCtor = new Vehicle(new GoByFlying()); $jetsByCtor = new Vehicle(new GoByFlyingFast()); $streetRacerByCtor->drive(); $formulaoneByCtor->drive(); $helicopterByCtor->drive(); $jetsByCtor->drive();