PerfSpy 3 -- PerfSpyDemo

I like dolphin! It is such an intelligent, playful and social animal. It can learn so many tricks, tail-walking, dancing, jumping, you name it. It can even innovate – creating new tricks on their own! Of course, if you have the world’s cutest bottom as a panda does, you do not have to learn tricks to please the crowd – hey, life is not fair and beauty is not just skip-deep.

I am going to use dolphin and panda in my demo, if you think it is silly, bear with me.

In this demo:

Animal is an abstract class with an abstract method playTricks(),Panda and Dolphin extends from it. Show invokes Animal.playTricks() to startAShow(). Animals have a Trainer. Notice how they are inside different packages, it is going to play a role in your Aspect.

public abstract class Animal {

        private String name;

        private Trainer trainer;

        public Animal(String name, Trainer trainer) {

                super();

                this.name = name;

                this.trainer = trainer;

        }

        public String getName() {

                return name;

        }

        public Trainer getTrainer() {

                return trainer;

        }

        public abstract void playTricks() throws Exception;

}

Dolphin does a lot of things in a show:

public class Dolphin extends Animal {

        private List friends = new ArrayList();

        public Dolphin(String name, Trainer trainer) {

                super(name, trainer);

                friends.add(trainer);

                //a bit narcissistic, friends with himself 100 times

                for (int i = 0; i < 100; i++) {

                        friends.add(this);

                }

        }

        @Override

        public void playTricks() throws Exception {

                shakeHands(this.getTrainer());

                tailWalk(10);

                for (int i = 0; i < 5; i++) {

                        backflip(i);

                }

        }

        private void addFriend(Object friend) {

                this.friends.add(friend);

        }

        private void tailWalk(int length) {

                System.out.println(this.getName() + " is tail walking " + length + " meters ...");

        }

        private void backflip(int index) throws Exception {

                System.out.println(this.getName() + " is backflipping " + index + " time ...");

//mimic slow methods

                Thread.sleep(1 * 1000);

        }

        private void shakeHands(Trainer trainer) {

                System.out.println(this.getName() + " is shaking hands with " + trainer.getName() + " ...");

                trainer.award(this);

        }

}

On the other hand, Panda simply needs to be a Panda:

public class Panda extends Animal{

        public Panda(String name, Trainer trainer) {

                super(name, trainer);          

        }

        @Override

        public void playTricks() {     

                beingCute();

        }

       

        private String beingCute(){

                return "being cute...";

        }

       

}

Here is a Show:

public class Show {

        public void startAShow(String type) throws Exception {

                Trainer trainer;

                Animal animal;

                if (type.equals("dolphin")) {

                        trainer = new Trainer("Lucy");

                        animal = new Dolphin("Noodle", trainer);

                } else {

                        trainer = new Trainer("xiaowang");

                        animal = new Panda("lingling", trainer);

                }

                animal.playTricks();

        }

        public static void main(String[] args) throws Exception {

                new Show().startAShow(args[0]);

        }

}