1
00:00:00,420 --> 00:00:05,850
Documents can be used to describe what a function does in the past three workbooks, LFG documents to

2
00:00:05,850 --> 00:00:09,480
guide your code, and this one is from Workbook four point three.

3
00:00:10,380 --> 00:00:15,000
Notice how easy it is to read, because very succinctly, it tells you exactly what the function does,

4
00:00:15,300 --> 00:00:18,210
what the parameters are and what the function returns.

5
00:00:19,500 --> 00:00:25,290
If you're working in a team of developers, you should have a document for every function, it helps

6
00:00:25,290 --> 00:00:29,340
collaborators understand what your function does without having to read your code.

7
00:00:32,619 --> 00:00:35,680
So in this lesson, you're going to learn how to write documents.

8
00:00:38,230 --> 00:00:43,120
First thing I need you to do is create a new class by yourself inside the section for project, create

9
00:00:43,120 --> 00:00:47,260
a new file named Comments Java and make sure the class has a main method.

10
00:00:55,400 --> 00:00:57,260
So we're going to start off by writing a function.

11
00:00:59,030 --> 00:01:02,150
Inside documents generate a random function that void.

12
00:01:03,790 --> 00:01:05,170
I'm going to call that Grete.

13
00:01:12,050 --> 00:01:13,550
And it's just going to print high.

14
00:01:23,700 --> 00:01:26,910
And just before the function, I'm going to write slash star star.

15
00:01:28,040 --> 00:01:34,850
And press enter a few times, and Java creates a skeleton first threat, a dark comment next to the

16
00:01:34,850 --> 00:01:36,770
first hour, I'm going to write function name.

17
00:01:40,220 --> 00:01:41,330
Which is Grete.

18
00:01:47,990 --> 00:01:51,110
And beside the last hour, I'm going to write inside the function.

19
00:01:59,980 --> 00:02:04,330
Followed by a bullet point that describes what it does and it prints hi.

20
00:02:10,460 --> 00:02:11,050
There you go.

21
00:02:11,110 --> 00:02:14,470
This document effectively describes whatever function does.

22
00:02:15,650 --> 00:02:17,690
Now we're going to write a function with parameters.

23
00:02:21,050 --> 00:02:22,160
Public static.

24
00:02:29,770 --> 00:02:32,680
It's going to be void and I'm going to call it print text.

25
00:02:41,330 --> 00:02:44,720
And it's going to receive, too, string parameters, name and age.

26
00:02:51,150 --> 00:02:53,340
And inside the function, I'm going to print high.

27
00:02:54,870 --> 00:02:55,350
I'm.

28
00:02:57,830 --> 00:02:59,690
Whatever name value was Pastan.

29
00:03:07,870 --> 00:03:09,880
And whatever age value is Pastan.

30
00:03:13,160 --> 00:03:13,940
Years old.

31
00:03:21,920 --> 00:03:25,460
And now, once again, before the function, I'm going to write Star Star.

32
00:03:27,860 --> 00:03:33,530
Press enter a few times and check it out, it recognizes the two parameters in my function.

33
00:03:35,000 --> 00:03:39,920
And now this is just the preference, but in brackets, I'm going to add the data type of each parameter,

34
00:03:40,700 --> 00:03:42,560
so the name parameters of type string.

35
00:03:44,930 --> 00:03:47,270
And the parameter is of type string as well.

36
00:03:50,260 --> 00:03:53,410
Now, like before, right, the function name beside the first star.

37
00:04:02,190 --> 00:04:06,720
And describe the function beside the last hour, so we'll say inside the function.

38
00:04:08,920 --> 00:04:09,460
Colin.

39
00:04:13,520 --> 00:04:18,750
I'm going to add a bullet point that says this function prince, the name and age is part of a text.

40
00:04:28,330 --> 00:04:31,300
Now we're going to read a function where they return value and documenter.

41
00:04:35,350 --> 00:04:37,420
I'm going to make a function that returns a double.

42
00:04:44,550 --> 00:04:46,440
I'm going to call it calculate area.

43
00:04:53,000 --> 00:04:56,060
And it's going to receive two parameters, length and what?

44
00:05:07,550 --> 00:05:12,080
And inside the function, I'm going to calculate the area of a rectangle by multiplying the length and

45
00:05:12,080 --> 00:05:13,730
width values that are passed in.

46
00:05:19,190 --> 00:05:21,230
And then I'm going to return the area value.

47
00:05:26,280 --> 00:05:29,820
And once again, right before the function, I'm going to write Star Star.

48
00:05:32,700 --> 00:05:38,490
Press enter a few times and check it out this time it recognizes the parameters and that you have a

49
00:05:38,490 --> 00:05:39,260
return value.

50
00:05:39,780 --> 00:05:43,080
And you know me, I like the data type of each thing in brackets.

51
00:05:43,590 --> 00:05:45,330
The parameters are all of type double.

52
00:05:47,100 --> 00:05:49,070
And the return value as a double as well.

53
00:05:56,480 --> 00:05:58,370
As always, I would add the function name.

54
00:06:10,050 --> 00:06:14,940
And next to the last hour, I'm going to describe the function by saying inside the function.

55
00:06:20,130 --> 00:06:24,510
And then I'll add a bullet point that says this function calculates the area and returns.

56
00:06:30,120 --> 00:06:31,800
That's all pretty easy, isn't it?

57
00:06:32,430 --> 00:06:38,190
All you have to do is press star, star a few times and Java creates a skeleton that we can use to fill

58
00:06:38,190 --> 00:06:39,840
out and document our function.

59
00:06:43,050 --> 00:06:48,690
In this lesson, you learn to describe functions using Javadoc when you write Star, a star followed

60
00:06:48,690 --> 00:06:54,960
by Enter Jova generates the format and all you have to do is write the function name, give a small

61
00:06:54,960 --> 00:07:00,300
description, and if you want to get super fancy, write the type of each thing in brackets.