1
00:00:01,070 --> 00:00:08,360
To demonstrate the prototype pattern in action, I have created this class here called robots, which

2
00:00:08,360 --> 00:00:09,350
implements skill levels.

3
00:00:09,360 --> 00:00:17,790
So just remind you, you need to implement this interface in order to use to implement the code method

4
00:00:17,810 --> 00:00:18,430
yourself.

5
00:00:18,920 --> 00:00:24,140
So the robot class has three properties here.

6
00:00:24,500 --> 00:00:25,370
One is very simple.

7
00:00:25,370 --> 00:00:26,660
It's a primitive type.

8
00:00:28,070 --> 00:00:34,160
The other one is a list of strings and the other one is another class called components.

9
00:00:34,160 --> 00:00:35,930
The components class is very easy.

10
00:00:35,930 --> 00:00:38,780
It has only two strings as as properties.

11
00:00:38,780 --> 00:00:45,530
And I get the sense that there's for those properties here, you can imagine that this this object could

12
00:00:45,530 --> 00:00:49,430
have been a lot more complicated than it is right now.

13
00:00:50,130 --> 00:00:57,080
Even this one has a lot of I mean, has to two objects and this array can be on this list here, can

14
00:00:57,080 --> 00:00:58,670
be very lengthy.

15
00:00:58,680 --> 00:01:05,240
So it will occupy a fairly decent chunk from from the memory.

16
00:01:05,250 --> 00:01:14,340
So it's it's actually very costly to have a lot of robots, objects created in your code.

17
00:01:14,960 --> 00:01:17,540
Here is the constructor in the constructor.

18
00:01:17,930 --> 00:01:25,220
I have initialize all the properties here and of course you have together since at the and the clone

19
00:01:25,220 --> 00:01:27,850
method, which is very important for the prototype.

20
00:01:28,730 --> 00:01:31,160
So here is a try catch block.

21
00:01:31,460 --> 00:01:40,790
We just need to return the execution of the super class section of the clone and we need to cast the

22
00:01:40,790 --> 00:01:48,290
result, the return of of this method to a robot, if not an object.

23
00:01:48,290 --> 00:01:53,660
If this will will result in an exception on the object, will be will be returned and let's see this

24
00:01:53,660 --> 00:01:54,160
in action.

25
00:01:54,350 --> 00:01:57,890
So I have created the main method in this class here.

26
00:01:58,310 --> 00:02:03,170
I have defined the features in the form of a retest.

27
00:02:03,260 --> 00:02:09,410
And here, as you can see, I created some tasks that a robot can can perform.

28
00:02:10,970 --> 00:02:20,350
Also, I added one component here just to make things easier to to understand.

29
00:02:20,360 --> 00:02:25,040
And also I have initialize here the first robot.

30
00:02:25,520 --> 00:02:30,260
So like I said in the previous video, we need to use the new keyword.

31
00:02:30,260 --> 00:02:31,300
Only at the beginning.

32
00:02:32,360 --> 00:02:35,860
The rest of the objects will be created using the clone method.

33
00:02:36,260 --> 00:02:43,430
So as you can see here, another robot is created and we call the clone method of the first robot that

34
00:02:43,430 --> 00:02:47,240
has been created within the cube using the constructor.

35
00:02:47,570 --> 00:02:54,280
And the thing to demonstrate here is that all these two robots are the same.

36
00:02:54,800 --> 00:02:56,990
However, these are two different objects.

37
00:02:56,990 --> 00:02:59,030
So these will have two different addresses.

38
00:02:59,040 --> 00:03:04,250
This will be stored in two different addresses in memory.

39
00:03:04,640 --> 00:03:12,500
So even though they share the same properties, they will have that there will be two separate objects.

40
00:03:12,800 --> 00:03:15,830
So let's run this and we should see the same.

41
00:03:16,900 --> 00:03:25,300
Objects outputted, so as you can see, the same properties here are outputted, so we see I.D. number

42
00:03:25,300 --> 00:03:32,260
one for both of them, which is not very correct in terms of of the logic for the application.

43
00:03:32,260 --> 00:03:41,800
But you can anyway change the ID of your uncle using the center and component here is just it's just

44
00:03:42,250 --> 00:03:43,690
the name of the class and the hash.

45
00:03:44,540 --> 00:03:51,250
You can see it is the same and the actions that the robot can can create.

46
00:03:51,260 --> 00:03:53,470
So as you can see, it works quite well.

47
00:03:53,740 --> 00:04:04,990
So whenever you have a situation when you can have a class, when it is very costly to instantiate the

48
00:04:04,990 --> 00:04:12,880
class twice, you and also you won't mind to have the same properties for the same for two different

49
00:04:12,880 --> 00:04:20,500
instances, then you may want to consider the prototype either because it's a bit more efficient to

50
00:04:20,500 --> 00:04:28,630
use it and also not very complicated, especially if you don't perform a deep clone, a copy of your

51
00:04:28,630 --> 00:04:31,060
object if this is called a shallow copy.

52
00:04:31,070 --> 00:04:37,980
So only the primitives and some some references of the objects are copied, not the objects themselves.

53
00:04:38,020 --> 00:04:38,370
Right.

54
00:04:38,380 --> 00:04:40,360
So not that component object.

55
00:04:40,360 --> 00:04:42,320
Only just just a reference to this object.

56
00:04:43,000 --> 00:04:44,350
So that's about it.

57
00:04:45,310 --> 00:04:46,680
Regarding the prototype.

58
00:04:46,800 --> 00:04:51,240
Join me in the next tutorial where we are going to discuss about object pull.

59
00:04:52,270 --> 00:04:53,740
So see you in the next tutorial.