Untitled

public interface BirdType {}

public class BlueJay implements BirdType {}

public class Cardinal implements BirdType {}

public class Canary implements BirdType {}

   

public interface BirdCamera<BT extends BirdType> {}

public interface BirdCall<BT extends BirdType> {}

public class BlueJayCamera implements BirdCamera<BlueJay> {}

public class CardinalCamera implements BirdCamera<Cardinal> {}

public class CanaryCamera implements BirdCamera<Canary> {}

public class BlueJayCall implements BirdCall<BlueJay> {}

public class CardinalCall implements BirdCall<Cardinal> {}

public class CanaryCall implements BirdCall<Canary> {}

   

public interface Photographer

  <BT extends BirdType,

   CAM extends BirdCamera<BT>,

   CAL extends BirdCall<BT>>

{

  CAM getPhotographersCamera();

  CAL getPhotographersBirdCall();

  void examineCamera(CAM camera);

}

   

public class BlueJayPhotographer implements Photographer<BlueJay, BlueJayCamera, BlueJayCall> {

 

  @Override

  public BlueJayCamera getPhotographersCamera() {

    //Do bluejay specific logic

    return new BlueJayCamera();

  }

 

  @Override

  public BlueJayCall getPhotographersBirdCall() {

    //Do bluejay specific logic

    return new BlueJayCall();

  }

 

  @Override

  public void examineCamera(BlueJayCamera camera) {

    //Do bluejay specific logic

  }

}

   

public class ConfusedPhotographer implements Photographer<BlueJay, CardinalCamera, CanaryCall>

   

public class PhotographerProvider {

  public Photographer get(int birdCode) {

    if (birdCode == 0) {

      return new BlueJayPhotographer();

    }

    else if (birdCode == 1) {

      return new CardinalPhotographer();

    }

    else if (birdCode == 2) {

      return new CanaryPhotographer();

    }

    else {

      throw new IllegalArgumentException("Unsupported bird code: " + birdCode);

    }

  }

}

   

public void importantMethod(PhotographerProvider photographerProvider) {

    // blah blah logic goes here

    int mostCommonBirdType = 1;

    Photographer typicalTourist = photographerProvider.get(mostCommonBirdType);

    BirdCamera cam = typicalTourist.getPhotographersCamera();

    typicalTourist.examineCamera(cam);

    // blah blah more logic here

  }