Would you like to inspect the original subtitles? These are the user uploaded subtitles that are being translated:
1
00:00:00,180 --> 00:00:01,850
This video was for Windows.
2
00:00:01,859 --> 00:00:05,430
If you're using a mac computer, please go to the previous lesson.
3
00:00:06,650 --> 00:00:09,410
Every developer should know how to use their terminal.
4
00:00:11,730 --> 00:00:14,820
So far, you learned how to run your code using the run button.
5
00:00:15,060 --> 00:00:19,530
Now, the run button is nice, but it's really important that you learn how to use your terminal.
6
00:00:22,350 --> 00:00:26,220
So in this lesson, you will run your code using terminal commands.
7
00:00:28,790 --> 00:00:31,640
Java C means Java compiler.
8
00:00:33,810 --> 00:00:39,900
So in step one, the Terminal command Java C is going to compile your Java code into byte code.
9
00:00:43,720 --> 00:00:46,840
Specifically, we want to compile the code inside of Hello, Java.
10
00:00:47,020 --> 00:00:47,650
Java.
11
00:00:50,990 --> 00:00:57,380
So tell your terminal we want the Java compiler Java C to compile the code inside of Hello, Java.
12
00:00:57,650 --> 00:00:58,310
Java.
13
00:01:01,090 --> 00:01:07,420
By doing so, the Java compiler will compile all of the Java code into a format called Bytecode.
14
00:01:09,420 --> 00:01:13,140
The compiled bytecode is going to live inside of a class file.
15
00:01:16,350 --> 00:01:17,220
From Vsco.
16
00:01:17,250 --> 00:01:20,280
You can open up a new terminal by going over to terminal.
17
00:01:20,430 --> 00:01:21,420
New terminal.
18
00:01:25,940 --> 00:01:30,020
And your terminal should automatically point to section one.
19
00:01:31,670 --> 00:01:35,360
The Hello Java Java file that lives inside of Section one.
20
00:01:35,360 --> 00:01:38,260
So over here we can compile the code inside of it.
21
00:01:38,270 --> 00:01:40,220
Java Compiler and Java C.
22
00:01:41,400 --> 00:01:43,140
And now press tab.
23
00:01:43,840 --> 00:01:44,950
By pressing tab.
24
00:01:44,950 --> 00:01:48,820
It guesses the file that I'm trying to compile by looking inside of the folder.
25
00:01:48,820 --> 00:01:49,640
Section one.
26
00:01:49,660 --> 00:01:52,940
There's only one file inside of section one, so it auto completes.
27
00:01:52,960 --> 00:01:53,290
Hello.
28
00:01:53,290 --> 00:01:53,590
Java.
29
00:01:53,770 --> 00:01:54,320
Java.
30
00:01:54,340 --> 00:01:57,340
Because you're using PowerShell, it adds a dot slash.
31
00:01:57,340 --> 00:01:59,380
Please remove the dot slash.
32
00:02:01,900 --> 00:02:04,420
And now you can compile your Java code.
33
00:02:12,780 --> 00:02:19,380
But anyways, by applying the Java Sea Command on our Java file, the Java compiler compiled all of
34
00:02:19,380 --> 00:02:24,510
its Java code into byte code, and the byte code lives inside of a dot class file.
35
00:02:28,070 --> 00:02:33,230
In step number two, the Terminal command Java executes the compiled code.
36
00:02:36,740 --> 00:02:40,820
So to summarize, the Java Sea Command compiles your code.
37
00:02:42,510 --> 00:02:46,820
And the Java Command executes the compiled code by design.
38
00:02:46,830 --> 00:02:50,090
The Java Sea Command includes the Java extension.
39
00:02:50,100 --> 00:02:52,260
The Java Command does not.
40
00:02:52,290 --> 00:02:55,890
So please be very careful when writing your commands.
41
00:02:56,550 --> 00:02:58,200
All right, Back to our project.
42
00:02:58,200 --> 00:03:01,680
We will write Java and then press tab.
43
00:03:01,710 --> 00:03:05,610
It's going to autocomplete based on what it finds inside of section one.
44
00:03:05,610 --> 00:03:07,980
And here it adds a dot class at the end.
45
00:03:08,010 --> 00:03:13,440
Now, I know that the Java Command is ultimately executing the byte code inside of the class file,
46
00:03:13,440 --> 00:03:19,680
but by design, the Java Command does not have any extensions at the end, so please remove it.
47
00:03:19,710 --> 00:03:21,240
Do not add a dot class.
48
00:03:21,240 --> 00:03:24,150
Do not add a java Java file name.
49
00:03:24,150 --> 00:03:25,140
That's it.
50
00:03:25,260 --> 00:03:27,060
It also adds a dot slash.
51
00:03:27,060 --> 00:03:28,620
Please remove that as well.
52
00:03:31,730 --> 00:03:35,030
Just like that, it's able to run the compiled code.
53
00:03:35,420 --> 00:03:40,550
What these two commands are doing is pretty much what their run button was doing for us behind the scenes.
54
00:03:40,550 --> 00:03:45,290
But I want you to be comfortable running terminal commands, so I'm going to keep using terminal commands
55
00:03:45,290 --> 00:03:46,550
throughout this course.
56
00:03:46,760 --> 00:03:52,270
Now let's say I want to re execute the compiled code instead of rewriting this command.
57
00:03:52,280 --> 00:03:54,410
What I can do is press the up key.
58
00:03:54,620 --> 00:03:59,900
The up key remembers previous terminal commands and we can use it to re execute the compiled code as
59
00:03:59,900 --> 00:04:01,460
many times as we want.
60
00:04:02,320 --> 00:04:03,040
Awesome.
61
00:04:05,520 --> 00:04:11,190
Remember that when you execute your code, Java looks for the entry point main, it tries to find it
62
00:04:11,190 --> 00:04:16,680
and once it finds main, it runs the code inside the first line of code inside main prints.
63
00:04:16,680 --> 00:04:17,790
Hello Java.
64
00:04:18,269 --> 00:04:23,010
Then it looks for more code inside main, but there isn't any so it reaches the end.
65
00:04:23,930 --> 00:04:24,490
All right.
66
00:04:24,500 --> 00:04:28,880
With that being said, I need to warn you to always compile your code first.
67
00:04:29,540 --> 00:04:35,990
When you make changes to your code, compile it first using Java C and then run the compiled code using
68
00:04:35,990 --> 00:04:37,310
the Java Command.
69
00:04:37,940 --> 00:04:44,540
Let's look at an example where I don't do that, so I'm going to change the message to Greetings Java.
70
00:04:46,790 --> 00:04:51,380
And now I would expect that by running this code, it should print this message.
71
00:04:51,620 --> 00:04:54,780
So just run the code without compiling Java.
72
00:04:54,800 --> 00:04:55,160
Hello.
73
00:04:55,160 --> 00:04:55,820
Java.
74
00:04:56,480 --> 00:04:57,470
And it still prints.
75
00:04:57,470 --> 00:04:57,830
Hello?
76
00:04:57,830 --> 00:04:58,280
Java.
77
00:04:58,280 --> 00:05:01,700
And that's because you're running the old compiled code.
78
00:05:02,570 --> 00:05:07,280
When you make changes to your code, you need to recompile it using Java Sea.
79
00:05:07,670 --> 00:05:08,500
Java Sea.
80
00:05:08,540 --> 00:05:08,960
Hello?
81
00:05:08,960 --> 00:05:09,320
Java.
82
00:05:09,560 --> 00:05:10,190
Java.
83
00:05:11,030 --> 00:05:14,900
And then execute the newly compiled code with the Java Command.
84
00:05:15,050 --> 00:05:15,710
Java.
85
00:05:15,710 --> 00:05:16,790
Hello, Java.
86
00:05:17,330 --> 00:05:20,270
And once you do that, it executes the new code.
87
00:05:21,560 --> 00:05:23,360
With that being said, congratulations.
88
00:05:23,360 --> 00:05:26,180
You executed your code using Java commands.
89
00:05:26,270 --> 00:05:30,110
So far you learn that all of your code must exist in a Java class.
90
00:05:30,500 --> 00:05:32,870
You created a class called Hello Java.
91
00:05:33,730 --> 00:05:35,110
Manage the entry point.
92
00:05:35,110 --> 00:05:37,270
This is where Java starts running your code.
93
00:05:42,200 --> 00:05:48,290
And finally, you can use the Java Sea Command to compile your code and the Java Command to execute
94
00:05:48,290 --> 00:05:49,460
the compiled code.
7997
Can't find what you're looking for?
Get subtitles in any language from opensubtitles.com, and translate them here.