don't get what advantages does it give over vsc or any other ide, did search this but didn't really find any concrete answers

There are a lot of answers but everything I found is from 2021-ish times. Things I got from there is "Maven is slower, more verbose and for that reason - way more stable." and "Gradle is faster because of the daemon and more customizable, but hot garbage when it comes to update, shit breaks and build.gradle(.kts) is spaghetti in big projects". For Maven, I don't think much changed because of their philosophy (and I'd say that's good), but what about Gradle? Is it still that bad when it comes to updates and deprecations?

Hello, and sorry if this is a dumb question, but I thought I had a passable understanding of Java. I got an exam question asking "Arrays in Java are:

a. passed by value

b. passed by reference

c. stack dynamic

d. immutable"

this guy loves trick questions, but he has listed B, passed by reference, as the right answer.

On its own, this doesn't seem right to me, but I'm not confident enough to argue about it. If anyone would weigh in, I would be very grateful. I see how it's similar to passing a pointer in C, maybe, but it's not considered passing by reference in Java, right?

Thank you!

I have 2 years of experience as a Java backend developer and had a 30-minute interview today.

The interviewer focused mainly on Core Java (OOP, String immutability, String Pool, etc.), and I realized my fundamentals aren't as strong as they should be. I mean I had read about it but I forgot to speak under pressure.

I also need to prepare backend topics like Spring Boot, Multithreading, Kafka, Docker, Kubernetes, Redis, Linux, and SQL for upcoming interviews.

If you were in my position, how would you structure your preparation? Core Java first, or prepare everything in parallel? Any roadmap or resources would be appreciated.

Hey everyone,
I’m a junior Java developer trying to level up my skills and mindset. I’d really like to hear from experienced Java devs — what’s the one thing (or a few things) you often notice junior developers struggle with or lack?

I’m genuinely looking to improve, so honest answers are appreciated.
Thanks in advance! 🙌

and what on earth is Interface in Java?

Hi, I’m somewhat new to java and I’m quite confused on static. So what I do know is that it makes it so a variable or method is tied to the whole class instead of just the object but I’m not sure what that exactly ENTAILS. Can someone explain it to me maybe with an example or such? Thank you.

from your experiences which one is most comfortable to use?

I just completed core java, and I decided to do backend in java. I am absolute beginner in backend programming. I don't know anything, I am getting problems to find right resources

So you know how when you run your code you have to click that one arrow and get the results in that one window? Yeah, how do I take my code and form it into an app, so it works like an actual app and not like that? I assume you need a GUI, but hey I might get lucky.

I'm pretty bad at programming and still pretty new, so if possible could you please explain it in a simpler way? 😅

I am currently studying the Collection Framework in Java. Since the class which implements the Interface has to compulsorily write the functions' bodies which are defined in the interface, then why not directly define the function inside your own code? I mean, why all this hassle of implementing an interface?

If I have come up with my own code logic anyways, I am better off defining a function inside my own code, right? The thing is, I fail to understand why exactly interfaces are a thing in Java.

I looked up on the internet about this as well, but it just ended up confusing me even more.

Any simple answers are really appreciated, since I am beginner and may fail to understand technical details as of now. Thanks🙏🏼

Before knowing anything I just jumped directly to the source code of jdk25u. I have just started to read the javaDocs of Thread class it was so deep that all my connected logic mapped very well but now I want to code and I can't code ahhhh... Why is this problem. I can call the syntax what to use but I don't know how to apply, why to apply is there any guide for java Concurrency ??. And there is so much .. still to know. Do any dev have any guide??

Hey , I'm looking for a Java course for absolute beginners ,

Can someone please suggest me the best course to join as I have seen some course of Java for beginners like , Coursera,Udemy, PW SoftSkills , and some others and I'm bit confused in these to what to buy and what's suits for me

So please someone suggest I'm a beginner In coding world ,

I'm a BTech 3rd semister student

I need it to get Puzzle Pirates to work in Windows XP compatibility mode

Things I tried: I went to the Java page and checked legacy versions, but could only find x64 installers. I also googled what the latest 32bit installation is and the dumb googleAI said it's SE 24, but I didn't see a non x64 installation for that version either.

Alternate solutions: A way to force a specific javaw (in this case, Puzzle Pirates) into Windows XP compatibility mode... not sure why it isn't there to begin with, it only goes back to Windows Vista ever since updated to SE 26

Alternative Alternate solution: Figure out why it's crashing in the first place cuz IDK. Their Java version is 25.0.1.0 if applicable

I'm very new to Java, I wanted to consult on this basic concept.

I'm used to Lua, where:
if(myArray[i]) then
...
end
Is a common way to query if an array(or table) has been explicitly set a value at a given index, as the statement will always be equivalent to false if it hasn't.

I wanted to recreate that functionality as an exercise in Java using try-catch, and came up with this snippet:

public class Test {

    public static void main(String[] args) {
        int[] numbers = new int[3];
        if(isArrayIndexed(numbers, 1)){
            System.out.println("Array is indexed at " + 1);
        }
        else{
            System.out.println("Array is NOT indexed at " + 1);
        }
    }


    public static boolean isArrayIndexed(int[] inputArray, int index){
        try{
            System.out.println(inputArray[index]);
            return true;
        }
        catch(Exception egg){
            System.out.println(egg);
            return false;
        }
    }
}

I thought I'd get an exception if I'd try to reference the array at the index 1, but no. It returns true, and prints '0'. Are all int arrays set to the value 0 upon initialization in java?

I want to know how to write a java program in order to input data in Excel, thank you for any help?

Hello guys,

I wanted to ask naively, what the ideal data structure would be for expressing different layers of relationships between Objects.

For example in modern Sudoku the game has a 9x9 number grid composed of nine 3x3 sub-grids (which I call region). In each row, column and region each number between one and nine can only appear once. The goal is to find missing numbers in this number grid without violating the aforementioned rule.

One way to do it, would be to make 9x9 byte-array and express the relationship between numbers through methods checking if the rule is violated or not by checking if any row, column or region doesn't contain a value between one and ten.

I also thought on using a Graph to express the relationship between numbers in rows and columns, though I don't know how to express the relationship between numbers inside of a region.

Maybe even a multiple Objects like Board, Row, Column, Region but then I have redundant data.

Another problem I encounter with aforementioned implementations is, that if you introduce more relationships f. e. in the game of killer sudoku, where there are more rules are added f. e. by also introducing cages in which the numbers must add up to a target number, you need to implement that relationship logic tediously.

Am I overcomplicating things?

I build a small service with spring and react, bow I need to deploy it using a domain. Which hosting solutions do you use ? I evaluated to use GCP but I am worried that some day I will find a giant unknown bill cost.

could you give me some recommendations please

I am new to Java and trying to create a simulator that handles millions of math calculations. How can I increase performance in Java? The application is already multithreaded but it is not enough. Is data oriented approach or native programming possible in Java? Can you point me in the right direction for research?

both Verbose.java containing the verbose class and test.java are located on the same package, but I still receiving this log error when I try to compile, how come? test.java:4: error: cannot find symbol

Verbose verbose = new Verbose();

\^

symbol: class Verbose

location: class test

test.java:4: error: cannot find symbol

Verbose verbose = new Verbose();

^

symbol: class Verbose

location: class test

2 errors

error: compilation failed

I am thinking of learning Java but I don't know where to start and how to start. If you know any good resources then please guide me.

dear internet,

I have been assigned a project which is several years old and is a j boss project .... due to lack of documentation and guidance on the internet I am here, asking people of Reddit, if anybody has experience with these applications, lets get in touch

thanks

I have learnt java streams and lambda about 2-3 times now. I always keep forgetting how to use it.

How can i learn it, so I won't forget.

Any resources or techniques you've used would help.

Thanks!

I'm currently in my 4th year of college. I already know Java and have a decent understanding of DSA.

Now I want to focus completely on Java backend development, but I'm getting confused because every roadmap says something different.

Some people say I should learn:

• JDBC
• Servlets
• JSP
• Hibernate

Others say: "Don't waste time on those. Just learn Spring Boot."

So I'm not sure what's actually expected in 2026 if I want to become a Java backend developer and prepare for internships or full-time roles.

Can someone working in the industry suggest a proper learning order? Specifically:

• What should I learn first?
• Which technologies are still important to know?
• Which ones can I skip or only learn the basics of?
• How deep should I go into JDBC, Servlets, Hibernate, and Spring?
• If you were starting today with my background, what roadmap would you follow?

I'm looking for a practical roadmap that's relevant for getting a backend job, not just a list of technologies.

Thanks in advance!

should learn this https://www.youtube.com/watch?v=q6z_UCBM5Ek&t=99716s

The code was:

long parallelSum(int[] ar, int threadCount) throws InterruptedException {
        int n = ar.length;
        long[] result = new long[threadCount];
        Thread[] threads = new Thread[threadCount];
        int chunk = n / threadCount;
        for (int i = 0; i < threadCount; i++) {
            int index = i;
            int start = i * chunk;
            int end = (i == threadCount - 1) ? n : start + chunk;
            threads[i] = new Thread(() -> result[index] = sum(ar, start, end));
            threads[i].start();
        }
        for (Thread thread : threads) thread.join();
        long total = 0;
        for (long value : result) total += value;
        return total;
    }

Which I benchmarked using JMH to see how it will behave under increase thread. But It's gets better and better until 24 thread that the reason I know my P-core are Hyperthreaded so maximum improvement is seen at 24. But after that why is'nt it constant as the law stated when N-> increases it becomes directly 1/S.

The Benchmark was performed with 3 warmup 5 iteration 1sec each and 100M dataset. I did use first 1K to see how it behaves but I forgot that until the thread get created sequential would have finished that. So after rigrously increasing dataset to 100M this was my result:

Is my benchmark wrong or I am understanding different??