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whats the best place to start to learn coding

so like should we watch a 40 min video on yt or use a specific applications to start since whatever ive done, i have learnt like nothing:1105happycat: so please tell me

Spring Boot question

I have a two part question that is slightly related. What is the best way to work with method params Using IDS...

How to delete list length - n amount of minimums from a DLL

//The new DoubleLL should have the n largest nodes in the SAME ORDER as the original SingleLL ​​`​ public static DoubleLL TopNodes(SingleLL list, int n) throws Exception {...

Java project using Swing

Hi, if anyone knows about Swing in java, there's a project i'm doing a To Do List Task, so i'm doing it between JFrame, one for adding the list, and other that displays when the user adds the new task, but I dont know how to storage the windows and show them into a Dashboard (Im currently saving them in a class which contains the List of Lists that the user adds), also, whenever the user wants to go back to the principal menu, it doesn't let me execute it, so if someone knows a better way to t...

Whats the point of Spring's MultiValueMap?

Hello everyone. I came across Spring's MultiValueMap and started wondering whats the point of it? How is it better than old school way? ```java Map<String, List<String>> myMap1 = new HashMap<String, List<String>>(); List<String> citiesInUSA = new ArrayList<>(); citiesInUSA.add("New York");...

App for Android and IOS

Not a Java Specific Question, but what Tool/Framework would you guys recommend in 2025 today for creating a App running on both Android and IOS?

New here, new to Java

Having issues with running jar files. Java and Javac are installed v23. Path is correct but it keeps saying unable to access jarfile... I ran cmd as admin and tried the following: Right click on file >> open with >> Java Platform SE Binary does absolutely nothing. Jar file I'm trying to run is an executable file. Uninstalled and reinstalled to v24. I tried a different jar file only to get unable to access jarfile (even tried moving it out of Downloads folder). These programs (jarfiles and Java) were downloaded from the official sites. I have issues with the Java program in the past too on other things but it has been too long for me to remember what so idk what's wrong I don't have a big knowledge of programming language or terms sorry, but I would like to learn...

Cant convert incoming message from RabbitMQ queue

Message converter in my rabbitmqconfig file: ```java @Bean public Jackson2JsonMessageConverter jsonMessageConverter() {...

Newbie

Hello, a newbie here, just starting Java Programming. I'm currently taking up Information Technology. Can somebody help me with the right programming for this? Exercise 3: String Manipulation Program Instructions:...

Resolution of Images in Swing

Whenever I add ImageIcons to my GUI using swing, they always are kinda pixelated. If I use pngs with higher resolution instead, they also appear bigger, and I can't manage to scale it down while keeping a high resolution. Do I miss anything here? attached is a screenshot from an icon in my gui in 1:1 scale, you easily can see how pixelated it is...
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Testing your SpringBoot, microservice based web apps

I want to learn about various kinda of testing in software development industry (more specifically, backend web app dev with springboot and microservices) and how to perform each of them in a java ecosystem (like springboot and microservices). I want to know just enough about concepts and then tools that help me perform it. I don't wanna be master in each but jack of mostly all, for now, or at least be able to implement most common testings. Please guide me. Thank you.

Using Class Api's

I'm in an AP Compsci class except I've like almost forgot anything so I was wondering if it was possible I could get some help/advice on how to do this?
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Downloading JIRA

Guys im trying to download jira and i need it asap because im asked to have it installed by work tomorrow which is in 6 hours. I figured the issue is wuth JAVA and im not good with JAVA. The install happens through a batch file that keeps crashing as soon as i open it and when i searched the issue up online it turned out to have something to do with JAVA.

Need help with college homework about making a algotrthm

guys I need help with my homework basicly it wants me to make a algrothm in java to find the average of 4 numbers

What do i need to do to authenticate my app?

Hello everyone. Ive app that has this in the config: ``` security: oauth2: resourceserver:...

How to efficiently implement balanced request queueing in Java?

I need to implement a balanced and highly efficient queue system to process a large number of requests. I have a Worker class that holds an internal queue for executing requests, and each Worker has a unique ID from 1 to n (where n is the total number of workers). If the number of requests exceeds a certain threshold (e.g., 1000), I want to distribute these requests evenly among multiple Worker instances (for example, with 10,000 requests and 1000 workers, each worker would handle about 10 reque...

shared database for multithreading

can someone help me with the trade-offs and pitfalls of creating a shared database? im building an uber-like project that needs to save a list of drivers and their state -as in free, or occupied in an another ride- across all threads. can someone guide me? its a console app....

JDTLS' code action/completion suggests really out of place things

I'm trying to use Neovim whenever I can, partly to learn it and partly because I just prefer it (when it works). One big annoying problem I run into constantly is the suggestions sometimes just breaks and suggests things like Listfrom org.hibernate instead of java.util. The fix is rather simple, just relaunch Neovim (just restarting the LSP sometimes works, but faster and more reliable to just quit it completely), but when I work on something new I may not notice that it happened again and I assume the autofill is correct. From what I've seen, other people have had similar experience with JDTLS on other editors so I don't think this is an LSP/neovim config problem (since it does work nicely otherwise, even better than intellij in some rare cases). None of the fixes I've seen (change jdk version, deleting JDTLS cache, etc.) works. I also tried using some Java-specific plugins for neovim but saw no or worse effect....
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Facing difficulties with the builder pattern

For a school excersise I need to Fix tests and code using the builder design pattern. However I am stuck and I don't know how to proceed. Specifically where and how I should Implement the builder. Here is a link to the repository with the work I have so far, any help is appreciated https://github.com/JuupStraathof/computerfactory...