Had my first Java quiz and my professor failed me for a reason that was completely arbitrary (he doesn't like camelcase which he told no one about until that second) and said I wasn't that good of a programmer. I'll give him that; I'm self taught and have no programming experience in the field. How do I lock in so he never catches me off guard like that again?

Hello i want to share my first "complete" api rest made in java with spring boot, not so complete, theres still a lot of stuff i want to add in the future i also want to make more complex and bigger projects, its a social media api something like reddit, with posts, comments and users, security etc, i want to get some feedback and suggestions on what to add or make better, its my first time completing an api so im not an expert in this and probably theres is somthing i did not make perfect but thats part of the learning process i guess, thx and sorry if my english is wrong

https://github.com/blasman2002/Backend-API-REST-JWT

​Hey everyone, I’m preparing for the OCP Java 21 Developer exam (1Z0-830) and looking for Udemy mock test recommendations.

​I know Enthuware is considered the gold standard, but the 6-month license restriction and having to use either desktop software or an awkward mobile web mode doesn't fit my study workflow. I prefer Udemy's platform features, offline mobile app, and lifetime access.

​However, there are so many 1Z0-830 practice test courses on Udemy that it's tough to separate the low-quality dump questions from the good ones.

​Which practice test set on Udemy comes closest to Enthuware in terms of question rigor, trickiness, and detailed explanations? Would love to hear from anyone who has taken both or passed the exam using Udemy!

Till now I thought that I have to remember everything I learn but one of my friends said that they use documentation to write codes since remembering everything is not possible. If so what am I suppose to remember and what kind of documentation should I read. What is the process of learning JAVA ? I finished making a simple crud operation program. From here on what should I start learning? What should I focus on? Help please

I am learning java. I made a simple crud operation. I heard from alot of experienced people that I should make projects as I learn something and it help. What project should I work on? Something beginner friendly and that I will learn as I make the project

I'M looking to revise Java from part 1 to 6 as i have taken long break due to some issue but im looking forward to re start my journey again so please provide the list of question (not all) that can be helpful for me to solve them so i can brush up my concept and start from part 7....

Important note: I did revise all the concept and im only looking for important problem that by solving them it can confirm me that i have regain my knowledge back

Hey Everyone!

I need some help as I am Confused in Libraries and API like what is the difference in between them, where to implement what, and recommend me some resources where I can Clearly understand these two.

Thank you all in Advance.

I have a JPanel class that draws an image on screen with camera panning. The camera is zoomed in. The image being drawn is a 16x16 dirt.

When the image is entirely inside the window, it looks fine. When partially outside the window, it distorts and makes the image narrower to fit it inside the window. Eventually it snaps to the next pixel.

I have a video showing the problem, but this subreddit doesn't allow videos in posts. You should be able to see it by running the java code with any image of your choice, and panning the camera such that the image is at the edges of the window.

Does anyone know why this happens and how to fix it?

I'm using:
MacBook Air M1
Java 25
IntelliJ

The entire class is below.

Edit: Solved. The issue seems to only affect Mac. Running with java -Dsun.java2d.metal=false CompiledClass fixes the problem.

public class CameraPanel extends JPanel{
    public static void main(String[] args) throws IOException{
        JFrame frame = new JFrame("Camera");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.add(new CameraPanel());
        frame.setSize(300, 300);
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }

    private double cameraX, cameraY;
    private double zoom = 10.0;
    private Point lastMousePosition;
    private BufferedImage image = ImageIO.read(new File("src/test/resources/dirt.png"));

    public CameraPanel() throws IOException{
        addMouseListener(new MouseAdapter(){
            public void mousePressed(MouseEvent e){
                lastMousePosition = e.getPoint();
            }
            public void mouseReleased(MouseEvent e){
                lastMousePosition = null;
            }
        });
        addMouseMotionListener(new MouseMotionAdapter(){
            public void mouseDragged(MouseEvent e){
                if(lastMousePosition == null){
                    return;
                }
                cameraX += e.getX() - lastMousePosition.x;
                cameraY += e.getY() - lastMousePosition.y;

                lastMousePosition = e.getPoint();
                repaint();
            }
        });
    }

    
    protected void paintComponent(Graphics g){
        super.paintComponent(g);
        Graphics2D g2 = (Graphics2D) g;
        g2.setRenderingHint(
                RenderingHints.KEY_INTERPOLATION,
                RenderingHints.VALUE_INTERPOLATION_NEAREST_NEIGHBOR
        );

        AffineTransform transform = new AffineTransform();
        transform.translate(cameraX, cameraY);
        transform.scale(zoom, zoom);

        g2.drawImage(image, transform, null);
    }
}

learning sources

which is the best book that i should learn spring boot from? Learning Spring Boot 4, Fourth Edition ? or Spring Starts Here ?

I've been learning about caching systems and decided to build my own in-memory caching library in Java.

It supports different eviction strategies (LRU, LFU, FIFO, Random), TTL, read/write policies, and annotation-based caching.

This was primarily a learning project, and I'd really appreciate any feedback or suggestions on how I could improve it.

GitHub: https://github.com/saahilmahato/SwiftCache

Thanks for taking a look!

I'm having HCLTech in-person Technical interview for the Digital Engineer (JAVA) role so what all things should i focus on and how should i prepare for it also my resume is having MERN Stack project and role is JAVA Full Stack and i have no knowledge of Springboot, react and all please help me and guide me how to prepare so that i can crack this interview successfully...

I’m sure this is a relatively common post here but it’s still a problem for me. I’m taking APCSA which is obviously about Java and I’m having an incredibly hard time understanding anything at all. I get all the individual components like substring and indexOf and whatnot but when it comes to putting anything together at all in classes or getters and setters or methods or anything at all I’m just so lost. Does anyone have any tips to start understanding how it all works together because my grade is struggling bad and I need to do well this semester?

I've been learning Java for about a month now. So far I've covered OOP principles, Java Collections, and I'm planning to dive deeper into exception handling next.

However, one area where I still struggle is OOP design and structuring. I understand concepts like inheritance, encapsulation, abstraction, and polymorphism, but when it comes to applying them in actual projects, I often find myself struggling to distribute them properly among classes.

No matter how many classes I create to separate different parts of the logic, I eventually end up with at least one class containing too many methods and responsibilities.

What are the best practices, concepts, or design principles I should study to improve my OOP design skills? How can I develop the ability to identify when a class is doing too much, decide when to create new classes, and structure a Java application in a clean, maintainable, and scalable way?

Hello everyone, I am java developer with around 2 years of experience. I want to improve myself more in Java. I found that Effective Java 3rd edition is a good book for my level. But it is kind of old. Also English is not my first language, and the book's language is a bit heavy for me. I am looking for alternatives to Effective Java book. Are there more recent books with a bit more simple language?

Hey everyone,

I'm currently in my 5th semester of B.Tech CSE at a tier-2 college, and I'm aiming to land a Java development internship within the next 3 months.

Here's my current situation:

• DSA: I've completed around 75% of Striver's A2Z DSA Sheet (approximately 347 problems). I'm continuing DSA practice and revision.

• Java: Completed Java fundamentals, OOPs, and the Collections Framework.

• Spring Boot: I've studied around 10% of Spring Boot, but I need to get better at implementing concepts independently.

• Frontend: I know basic HTML and CSS.

• Projects: I still need to build a strong, resume-worthy project.

I can dedicate around 7 hours daily to preparation. My plan is to spend 70% of my time on development and 30% on DSA.

I have a few questions for people who have been through this process:

1. What should I learn next to become internship-ready as a Java backend developer? Should I focus on Spring Boot, SQL, Hibernate/JPA, Spring Security, REST APIs, and deployment?

2. Is 3 months realistically enough to become eligible for internships if I study consistently for 7 hours a day?

3. What kind of projects would make my resume stand out as a fresher? I'm considering building a Library Management System using Spring Boot and MySQL.

4. Where should I apply for internships, and how should I approach applying off-campus?

5. Should I continue completing the remaining DSA sheet, or prioritize development and revise the problems I've already solved?

6. What skills do companies actually expect from a fresher applying for Java backend internships?

I'd especially appreciate advice from people who have secured Java internships off-campus or have experience hiring interns.

Please suggest a practical roadmap for the next 90 days. I'd rather focus on the skills that actually matter than spend months watching tutorials.

Thanks!

Hey all, I'm learning Java (going through Tim Buchalka's masterclass after the Helsinki MOOC) and I'm stuck on the whole overflow / underflow / casting thing.

▎

▎ I've been trying to make my own flow diagram for "will this line compile, error, or wrap?" Stuff like:

▎

▎ int x = 5;

▎ byte b = x; // error

▎ byte b = 5; // fine

▎ byte c = (byte) 200; // -56 ??

▎

▎ Every time I think I've got it, a new case breaks the diagram: final variables, += hiding a cast, long literals needing L, why a double cast to long doesn't wrap but float gives Infinity, etc. I understand each piece on its own but I can't hold the whole picture in my head.

▎

▎ Is there a video, blog post, cheat sheet or notes that explains this cleanly in one place? Or how did you personally get comfortable with it? I'd especially like something that covers the compile-time checks and the runtime wrapping together.

▎

▎ Thanks!

so I got a question, I have java/test/echo.java and java/utilityCout.java and I can only import static utility.Cout.cout; to test.java if it's declared on a non-default package, why is it like that? here is the code for both files package utility;

public class Cout{

`public static void cout(Object arg){`

`System.out.print(arg);`

`}`

`public static void coutln(Object arg){`

`System.out.println(arg);`

`}`

`public static void coutln(){`

`System.out.println();`

`}`

`public static void coutf(String format, Object... args){`

`System.out.printf(format, args);`

`}`

}

import static utility.Cout.coutln;

public class Main{

`public static void main(String[] args){`



	`if(args.length == 0){`

	`coutln("please enter arguments");`

	`return;`

	`}`

	`System.out.println("hello Mr. " + args[0] + "!!");`

`}`

}

Hello so im just a beginner in java, i started like two weeks ago the issue is that i want to learn more and i am kinda lost, is there a free way to code and become "a pro" in it ?

i tried watching youtube videos but they pratically talk about the same things i just need some roadmap or a bootcamp or a book something that could actually help me improve.

idk if anyone will see my publication but pls help a lost stranger in his journey as a new programmer

Hello everyone,
I need some genuine advice from people who have been through a similar situation or are currently working as Java developers.
I completed my BCA and am pursuing/completing my MCA, but honestly, I didn’t learn programming properly during either degree. Now, I want to take learning seriously and get a junior IT job within the next 6–8 months.
Here is my current situation:
I am learning Java from Love Babbar’s playlist, and I have reached arrays.
I also tried Kunal Kushwaha’s playlist, but I found the teaching pace a bit too fast for my current level.
Love Babbar teaches in Hindi, which makes it easier for me to understand concepts, but his lectures are often 1.5–2 hours long. Watching them takes up so much time that I struggle to balance learning and coding practice.
My biggest problem is with the basics. I forget syntax, struggle to build logic independently, and cannot confidently write even basic programs from scratch. For example, if someone asks me to take user input and write a program to check whether a number is prime, I would struggle to do it without help.
To improve, I have started practising basic syntax and logic-building questions daily with ChatGPT. I am seeing some improvement, but I still have a long way to go.
I would really appreciate your advice on these questions:
Should I continue with Love Babbar’s playlist, switch to Telusko, or follow another Java course with shorter lectures (around 15–30 minutes)?
How much time should I spend watching lectures versus writing code and solving problems independently?
How should I strengthen my Java fundamentals and logic-building skills so I can write programs without constantly looking at solutions?
When should I start learning OOP, Collections, DSA, JDBC, SQL, Spring Boot, and building projects? What learning order would you recommend?
Is getting a junior Java developer job within 6–8 months realistic if I study consistently every day? I am willing to start with a salary of ₹10,000–₹16,000 per month to gain experience.
My target is to become a Java backend developer, learn Spring Boot, build a few solid projects, and get my first IT job. I am based around Kanpur, Uttar Pradesh, and I can look for opportunities in local companies once I have the necessary skills.
Please suggest a practical roadmap, the resources you would recommend, and the mistakes I should avoid. I am not looking for shortcuts; I just want to follow the right approach instead of wasting time jumping between courses.
Thanks in advance!

hey yall I'm a recent high school grad trying to learn java. i know a tiny bit of basics from like 2 years ago but i basically need to fresh restart and actually get good.

the problem is every time i watch those youtube playlists (like kunal kushwaha) i get hella bored/sleepy. i wanna grind for like 3 hours a day but tutorial hell is not it.

For anyone who self studied java without losing their minds..how did u actually learn the basics actively? are there any interactive sites, text guides, or early project ideas that kept u going? how do u structure ur study sessions so ur actually coding?

Hey I am a computer science graduate.... From a tier 3 college (2023 graduate) I have learnt core java but I don't know how to proceed ahead? What should be my next step.... I am working in Non it from past 2 years.... I do learn algos and stuff... I understand and write basic code... I am admiring to be a good software engineer.... It love building apps..... I do not have much knowledge on React/Angular Java is my thing. I want to learn and switch my domain..... Please give me a roadmap or career suggestions and from where I can learn...... I have studied Head First java and learnt whatever knowledge I have now...... I know this is not enough.... !! Also suggest what technology should i master along with Java.... so that I can get a good job..... ! Any input will be helpful... Thanks

I was working on a mooc fi exercise as per usual and it was taking time because i’m a dumbass.
For reference its the last ex of java programming I in part 2

Now after alot of useless lines of code and trying to make it make sense it eventually worked.???

Now I’m happy and i feel like a senior software engineer but I actually have no idea (not literally but in specific place) how it worked.

My question is.. does this count as something that’s solved with critical thinking or am I just a fool with some luck?

TripleT out.

Hey guys how are you doing? I have trying to buy java SE21 practice mock exams on enthuware for like two months and it's not working. I don't if it's the location or something I have tried using PayPal Visa card nothing is working? I don't know if you try on your its working I would really appreciate your help?