Learning Java: #1 – Setting up BlueJ, Writing HelloWorld…

In this tutorial you learn how to set up BlueJ and the basics of Java by creating your HelloWorld class. Sorry for the font being small I increased it in the other tutorials so it’s not as much of a pain to look at.

Link to BlueJ:

Check out these books if you are serious about learning Java!

Beginning Programming with Java for Dummies

Core Java, Volume II — Advance Features (9th Edition) (Most up to date)

Java, A Beginner’s Guide, 5th Edition


Kast Dan says:

Hi when i tried to compile, i got an error (package System does not exist)
Please advise.

xXGamerManXx You says:

Thanks you! This was the first java tutorial i have ever watched. This has taught me alot, im here in 2017 coding like a pro. i remember the memorys. Thanks!

DJustine Geronimo says:

LOL Private static hahah

Cyberpunk Computing says:

I was wondering why the main method was set to private. Lol. I came here to figure out Blue J. It is an interesting IDE very minimalist. Almost no different than using a text editor. I found Blue J in my raspberry pi and wasn’t sure how to run after compiling. Thanks for the help.

Arham Upadhye says:

from next time make sure that you explain it quickly.

All or Nothing gameplay ! says:

when i compile it, it hi-lights the .out in system.out.println in red and says “package system does not exist” and will not let me go to “void main(String[] args)” please help my code is;

public class HelloWorld
    public static void main(String[] args) {
        system.out.println(“Hello World my name is (think of one later)”);

Felixo says:

WOHO! THANKS MAN 😀 Gonna watch all your tutorials! 

Jonathon Goodson says:

I feel like I just watched a tutorial by Jim Breuer’s character from Half-Baked. But I like it!

Mohit Kst says:

Can’t believe u don’t know what to call those.

Robert Galvin says:


MercifiesProductions says:

+Salman Samie because importing java.util.* is for typing input into your program. This lesson doesn’t do that, the program you make only outputs the helloworld statement. If you import something and don’t use it, the compiler will throw you an error.

GeishaTheSerpantClan says:

Funny tutorial 😀


smoking some weed before making the video i guess! krkrkrkr thanks man !!

Aidan O'Donnell says:


Ablequerq says:

Pajeet pls clean your desktop.

Ardy says:

Love the series so far! Hope you can upload more 😀

Ram Dato says:

Couldn’t you start with explaining what class, method and all the stuff are? This is really not understandable for begginer?

Syazani An says:

Mamat ni bantu banyak gila. Thanks Mercifier!

Iphecle Kennedy says:

wow this really is caps sensitive got error for writing system with a small s

Joseph Bentley says:

Big up the University of Kent, well weird one of my lectures helped create BlueJ

Andrew Hedman says:

They’re called QUOTATION MARKS.

solwolfpunk says:

Nice tutorial. Thank you. You may want to edit a mistake you made. These { } are braces and not brackets. [ ] are brackets. Not a big deal but it prove confusing to some.

MercifiesProductions says:

+Danielspringermusic +Music By

When you run it and the compiler opens, click on Options>Clear Screen at Method Call.

playtech says:

Why the hell you stretching the lecture ..why dont you start directly

Joseph D says:

This is what i get when i try doing it:

HelloWorld.main({ })
Hello World my name is Joseph.

Any help about this ?

Joshua Shook says:

what does package not exist mean?

TheCrunexianGeneral says:

This just made my day lol 

Dramic - Minecraft says:

thanks I did’t know that i could do java because i an just 9 yers old

Camille Atienza says:

Hi MercifiesProductions!! Do you have a tutorial on bluej that asks for a certain name then count and display the vowels used in that certain name. If not can you pls make..thank you!! 😀

Joson Mathew says:

Can’t I just do public static void main() 

Seems to work for all my programs

Karl says:

Hahahahahaha I spent about 30 minutes getting mad at myself when I realized I was typing printin instead of println. What the heck is wrong with me.

Craig HurpinDurpin says:

Hello, MercifiesProdcutions..

I am a beginner programmer, and I hope your tutorials help me out a lot. However, I noticed you didn’t know what some things were called. WhenYouTypeLikeThis it’s called CamelHump typing, and theres “” are called quotation marks.

Sabiq Khan says:

Do you study at the university of kent?

Roland Brake says:

you are cool man i love it. smoking some weed before making the video i guess!

MercifiesProductions says:

+Joseph Dukmak

I can’t reply to your comment, so I’m not sure if you’ll see this. You have comment replies turned off.

Post your code so I can look at it

xXGamerManXx You says:

Brings back memory. You are an awesome teacher, this was the first coding tutorial i have ever watched.
Now i’m coding like a pro! Thank you very much!

Akasha shafiq says:

i use println and its giving an error that expected

Intas Macaraig says:

amazing tutorials

Lit Homie says:

public static void main(String[] args) {
System.out.println(“I really liked this video thank you xD”);

5hubham Mins says:

when I click on new class there is no applet option on my bluej please help!

hari aditya says:

you can also write without using public,private,static,string[ ] args for normal programs.

Zhuoyan Zhou says:

I don’t think it’s boring I think it’s very interesting to watch your videos. My lecture gives lessons on PPT in the lecture hall and we have no practical practices while listening. And that is real boring…

Tyler H says:

Hey man, I’m going to be a sophomore in high school and I’m taking AP Computer science. We are using Blue J and Java just like this. I just wanted to let you know you are helping me a lot with this, I just wanted to get a head start over the summer and you’re making it much easier on me

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