02. Interface Segregation

 

EXAMPLE 01

Issue:

interface Vehicle {
  void dive();
  void fly();
}

class Car implements Vehicle {
  @Override
  public void dive() {System.out.println("InterfaceSegregation.Car dive");}

  @Override
  public void fly() {
    //This not needed to a bike
          }
}

Fixing That issue:

interface DrivingVehicle {void dive();}
interface FlyingVehicle {void fly();}

class Car implements DrivingVehicle {
  @Override
  public void dive() {System.out.println("InterfaceSegregation.Car dive");}

}

class Plane implements DrivingVehicle,FlyingVehicle {
  @Override
  public void dive() {System.out.println("InterfaceSegregation.Plane dive");}

  @Override
  public void fly() {System.out.println("InterfaceSegregation.Plane fly");}
}

EXAMPLE 02

Issue:

class PetrolEngine{}

class Vehicle{
    private PetrolEngine engine;
    Vehicle(PetrolEngine engine){this.engine=engine;}
}

Fixing That issue:

interface Engine{}
class PetrolEngine implements Engine{}
class DieselEngine implements Engine{}

class Vehicle{
    private Engine engine;
    Vehicle(Engine engine){this.engine=engine;}
}