public class MainClass {
public static void main(String[] args) {
Jet jet = new Jet();
jet.setGoAlgorithm(new DriveEngine());
jet.go();
jet.setGoAlgorithm(new FlyFastEngine());
jet.go();
jet.setGoAlgorithm(new DriveEngine());
jet.go();
}
}
abstract class Vehicle {
Engine goa = null;
public Vehicle() {
}
void setGoAlgorithm(Engine goa) {
this.goa = goa;
}
public void go() {
this.goa.go();
}
}
class Jet extends Vehicle {
public Jet() {
}
}
interface Engine {
public void go();
}
class FlyingFastEngine implements Engine {
public void go() {
System.out.println("Now I'm flying fast.");
}
}
class DriveEngine implements Engine {
public void go() {
System.out.println("Now I'm driving.");
}
}
class FlyFastEngine implements Engine {
public void go() {
System.out.println("Now I'm flying fast.");
}
}