Java Main Method Explained - What Does All That Stuff Mean?

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Full tutorial - What does public static void main (String[] args) mean in all your Java programs?
Get the full explanation of the Java main method in this lesson.
Public? Static? Void? Everything about the Java main method is explained.
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[@SponkADonk]

For whatever reason I have struggled with really understanding "static" and you just cleared it up for me. Thanks, John!

[@beesetti.d.ssubhash5075]

Can you please explain with an example. 😊

[@jumpz5561]

@@beesetti.d.ssubhash5075 if a method in a class is static, you'd need to create an instance of the class "Class1 class = new class()" in order to call the method, however if isn't static, you wouldn't need to to create the "Class1 class = new class()". You can directly call the method by writing Class1.method

[@jumpz5561]

does this make sense?

[@AK-wc1cv]

@@jumpz5561 Or is it the other way round

[@CodingWithJohn]

Yeah it's the other way around. If it's static, you can (and should) call it directly on the class without creating an object. But if it's not static, you have to create an object and call the method on the object.

[@alihaydarkaya3336]

helloJohn, sometimes I’m having a language barriers but when you explain I don’t feel that. I appreciate it great explanation.

[@InvinciRD]

The reason why i love this channel is the explanation is just like the way it's needed and basics are at-least a bit clearer than what we know already.

[@ThatOtherAndi]

man i just stumbled upon your channel and im simply blown away by the quality of your content, it's gold

[@yadnyeshdesai6652]

Hey John, you are providing a great educational value. Your videos always help to clear my doubts and understand the basics of Java. Keep it up. Thanks a lot.

[@caffeinatedpanda1511]

the scenario at the beginning was LITERALLY MY EXPERIENCE. tysm

[@heetwarm7819]

After al those hours searching for explanations this is the only video I found helpful and entertaining! Keep it up!

[@nick-yr7wu]

You seriously deserve more subscribers. You are an amazing teacher, thank you John

[@sabeennawaz1001]

Yes, that's why I told all of my classmates about John. We call him "Java John"

[@nobody_AskedMe]

I started watching your videos yesterday and I am subscribed now, very interesting explanations!

[@charityg4786]

You are so enthusiastic when you teach. thanks for the lesson,it was easy to understand

[@CodingWithJohn]

Very glad to hear that, thanks for watching!

[@felifrit]

this is my favorite channel for clearing up Java concepts, thank you so much John

[@Catalyst313]

I don't wanna underrate any of your other videos but this one (especially the introduction) really got me insanely immersed

[@hexagonmagnetics569]

The elephant in my text editor has been explained, thanks! I’ve watched a bunch of java youtubers, but you are indeed the most thorough with explaining java concepts!

[@findlestick]

Way to clearly explain things. Thank you. 👍

[@LaGrossePaulik]

Thank you so much!

[@spancavil]

Extremely useful! Congratz John.

[@mahodaadikari4116]

Your explanations are amazing. Keep up the good work. Wish you all the best ❤

[@LanceLiebenberg]

Thanks so much bro. This honestly helped so much. Walking away a little more confident 👍

[@victoriagee1059]

0:23 no one quite says that. They just say they’ll discuss it later. Lol but you are such a good teacher. Happy I found you!

[@kebbil]

and never do

[@nonnodacciaio704]

@@kebbil in any course you'll go over classes, methods and arguments, so you should be able to figure out what it does by yourself. Besides, they went over this in my course without even us asking

[@vu5700]

thats what your wife says the first time you are having sex with her

[@theboss-by5gd]

well ur lucky if they do.My teacher didnt say anything,she just said thats a default in java.So it really depends on the kinda teacher u hav

[@pranavnyavanandi9710]

It's quite straightforward once you get into the language. Initially, they give a vague definition so you can go on with the learning.

[@boulettefranck2627]

Three years later, i've "super appreciated" your video ! Thx 🤩

[@Noah-vm8id]

This was a video I was always looking for when I was a beginner, thanks 🙏

[@evanmcgillivray8697]

Thanks for the video! Great stuff man

[@lastwish6428]

It feels good , when you already know all these stuff and still watching this complete video 🤗

[@ramyareddy6190]

yours the first channel i subscribed after watching many others.. you are just too good to be on you tube. I love your videos.

[@samaravadi3]

I'm studying for my theory final in a couple days and you're helping me tremendously

[@mattmartin26]

Finally, a clear, succinct, and helpful explanation!

[@CodingWithJohn]

Glad it was helpful!

[@henriquesenadev2194]

Great and simple video! Congrats and thanks

[@steveymcsteve0717]

Thank you for this. I was always wondering what it all did and I could never geta good answer.

[@mythicaldata6297]

Great video, when I was taking java at university I felt they had way too many analogies, that by the end of them I was just confused and bored, and didn't answer stuff like this fully glad to heard a nice clear explanation instead of something like "you'll learn that later"

[@gopalkannan4934]

Thank you. It is useful for interview

[@user-dv1km1vk4b]

Thank you a lot❤❤ you are really helpful and you are very understandable

[@gregorriusadolphus2729]

This was very helpful....I just started learning Java last night (I was a JavaScript guy) and this really cleared things up! Gracias!!

[@JoseThomas-erpjose]

Wow, Never knew what it means. Super simple explaination

[@anth0ni33]

This is a very fun and easy to understand explanation. I'm not even a java developer (learning c#) but I understood it perfectly. I've noticed java and c# share similar syntax tho.

[@colbyboucher6391]

Might be good to note that those main args are typically used for advanced configuration options.

[@FREDDYMAZENGE]

bro this video made me subscribe without any hesitations ...... l like the way you started your video

[@franciscogrosso6533]

Amazing explanation, thank u so much!

[@abdennadhermayssa1890]

Super clear great job and thank you

[@jonathanbyrdmusic]

“Args” is actually the sound I make trying to understand computer language

[@hexagonmagnetics569]

I would like a big o notation lesson on search algorithms! Please discuss the space and time complexities of various algorithms and their most suitable applications!

[@saptarshidey7672]

Hello John, I really like the way you teach. Absolutely great!!! On similar lines to this video, students most of the time also think about the real stuff behind System.out.println(). Can you create a video explaining each part - What is System, out, println? Also the static nature of out and thus it can be used on top of the System class directly instead of an object. Cheers

[@CodeKurdi]

you are Legend man, lesson with fun and a lot info:)

[@elvispontes4165]

your videos are awesome!! Thanks a lot for sharing

[@furkancakin1553]

Hi John !!! I have been following you and watching alllll of your Java tutorials all the time would love to meet one day if you are anywhere near east coast !! I realized in this video though you are very quiet 😊 are you trying to to not wake someone up at home ??!! 😛 you are great thank you so much for al the useful info ! I hope the best for you

[@yashchandak8016]

Great explanation sir

[@philbowden]

Thanks for this. Nicely done. One question I have is can you think of a realistic use case for assigning value to the String[] args array?

[@Galasssss]

Watching your videos bring me the feeling that I could talk to you drinking a beer and learning a lot of coding stuff for HOURS. You're funny and smart, and know properly what you're saying. Amazing

[@saraproetti5039]

you are amazing teacher! Thank you

[@skylarngoi3262]

Thanks for your explanation..

[@mahodaadikari4116]

Super cool and amazing explanation 👏🏻❤

[@anonimosilva6723]

Another clever idea: if it's an array of strings, you can also modify it to an array of integers! It works similarly! Thank you for this excential explanation!!

[@MrSajjadgul]

A must like from me for all of your videos.

[@MrsWeasleyking15]

this was so clear thank youu

[@ROSUJACOB]

Thank you John for the video.

[@bladezxc]

Very nice videos, thank you so much

[@sebon11]

Lovely tutorial!

[@tibettenballs4962]

learning java has helped me realize the underworkings of languages. wonder what C++ would be like now (did it in high school 26 years ago.)

[@Mohanadxd]

John you are absolutely legend

[@sandralane6379]

Wonderful thank you!

[@michalski9141]

havent watched the video yet but: public - the accessor, means the method is accessible in other classes; static - the class doesnt need to be instantiated to be called; void - the return type, it does not return anything; main is of course the name and it takes in command line arguments represented by an array of strings called args

[@pradiptonath4323]

Great explanation

[@justinbanza4751]

Thank you very much for this video

[@vineethgajjela747]

thanks for the explanation

[@vodkaaaxxx]

well, you can explain the main name is because of the fact that the JVM is actually looking up the method via reflection. Basically you specify the class you run, for that class, reflection looks up for a method called exactly "main" with arg0 of type String[]

[@akeemlouigarde4946]

Thank you John

[@samim7373]

Thank you for sharing, I was hopping you can explain it better than others, can you try to explain it with example for a beginners that we can understand it easily.

[@vigneshwaranr680]

Love your teaching. I mean it ❤

[@musicvibes1146]

thanks john im a 7th grader trying to learn java this video helped out a lot thanks

[@ArjunKumar-zu2kl]

Brilliant John....

[@fyh8848]

Interesting, thx. Btw, the word “main” is inherited from C language. main function is entrance point in C.

[@10F2C]

the int main{} thingy?

[@tobiassteindl7792]

Perfect, thank you

[@Mnogojazyk]

Hello, John! How does one delimit the arguments args[x], one from another? How does one count the arguments? I expect there is a method to do just that. Nice explanation. Many thanks.

[@valoriebroderick]

It would be awesome if you could do a video just on the static keyword. Why would you use it besides in the main method and stuff.

[@user-pr9pq8en2d]

I love you man, I really needed this video.

[@ericamuhammad5082]

Thank you!

[@katiescape]

My mind always asks me 'why' and when I can't get the answers my learning shuts down, thank you for this explanation!

[@suwatchainanchai6637]

Do u have a video that teach about java command and show what the behind scene of the command working ? .and may be about maven and gradle that would be great too.

[@davishek7]

Neither college teachers nor the textbooks ever explained what args do. Thanks for the clear explanation.

[@adelacristea153]

Yep.... that was my teacher, like:" no more questions" :-/ Thank you for this great video. :D

[@TezlaByte]

Haven't seen the video yet... But that's exactly what I asked yeaaars ago trying to do C# I never progressed.

[@sasa-bv9gu]

Great video! Though I've got one question left. How do I pass multiple arguments (so that the args array contains more than one string)?

[@yashjani99]

Printing that args[0] gives the actual executable name in case of C/c++, can we similarly access the executable file name using this args variable? Or if there is other way, then how to do that?

[@shivjyotigarai2141]

1. jre calls the public main() 2. static methods in a class can be called without creating an instance of that class. Just call MainMethodExplaination.main() 3. void because does not return anything. 4. String args[] => passing arguments as an input .

[@vaibhavkulshreshtha6]

Is there any reason to leave line 6 and writing public static voin main(String[] args) { in 7th line Just wondering cuz even if you write it on 6th line it still work.

[@preetavasan8958]

Can you do a series on backtracking and dynamic programming

[@bacon37460]

Perfect John, please upload design pattern serie in JAVA.

[@MrJayenta]

Sir please upload some on spring boot course

[@duongvutung2876]

Thank you

[@MUZICSTATION1]

Hi John, I've one doubt Can we use (Object[ ] args) instead of ( String [ ] args) in main method. If we execute that program by add Object[] will not give output, why? 😅

[@michaelmai25]

omg...bro is better teacher than all my professors combined lol GREAT VIDEO!

[@m.morotha7095]

Thank you,

[@danielnoguera2219]

Thanks a lot! Cheers from argentina

[@alexzink4451]

Hello, Sir! We'd all really appreciate if you break down SOLID on this channel, especially LSP🙏🙏🙏

[@Nain_9]

Thanks bro

[@brijkumar8207]

Hello I have search so many videos on public static void main. But this is the first one that is clearer. You made it lot easier. You have any courses I can take?

[@CodingWithJohn]

Thanks! There's one linked in the description if you're interested. You can see all the content that's included and watch a few lessons free before you buy anything.

[@brijkumar8207]

@@CodingWithJohn I already code but I get confused on how to start

[@albertosoto4280]

THANKS A LOT! People just saying "just copy this" was driving me nuts.

[@CodingWithJohn]

Glad it helped! When you're first getting started it can be kind of overwhelming and confusing to understand everything that's going on with it, so "just put it in there" isn't terrible advice for your very first program. But after a while it's valuable to be clear why it's all there.

[@bhartiyagamerzzyt_]

Thanks a lot John. Appreciate the clear explanation! :) qq - you said the JRE will access your mail method like className.main() so is it jre or jvm that accesses our main method ?

[@NotreallySerious695]

You can visualize it in terms of three circles JVM( Java Virtual Machine) I think being the largest and containing JRE (Java Runtime Environment) which contains the the program( .Class file) . JRE is basically needed when you execute a program (.class file) and JVM when programming the java file ( JVM in simple terms converts the java file you have written into ".class" File which the JRE understands). So JRE is the one that accesses the main method.

[@clutchmadness]

You are fantastic.

[@Imsulaf]

The story in the beginning is so accurate

[@oldgamer1157]

thanks bro