JCH

Java Community | Help. Code. Learn.

We are a Community full of Java developers. You can come here to connect other devs, get help, help others and do many more things!

Join

JCH

Java Community | Help. Code. Learn.

We are a Community full of Java developers. You can come here to connect other devs, get help, help others and do many more things!

Join

java-help

❓︱qotw-answers

SidKid

4/5/2025

killing vs interrupting a Thread

what is the machine functionality difference between killing vs interrupting a Thread and why do we no longer use killing a Thread? maybe something to do with error handling idk

dghf

4/5/2025

`java.lang.NumberFormatException` in StreamCipher - Key Parsing Issue

Why am I encountering a java.lang.NumberFormatException in my Java StreamCipher program for a simple stream cipher task? Could someone point me in the right direction? The error occurs when I try to parse the key from the command line arguments using Integer.parseInt(). Specifically, the error message says "For input string: "4294966017"". Here's the relevant snippet from my StreamCipher.java main method: ```java...

The Next Guy

4/5/2025

Thoughts about my Security Implementation

So the basic idea is that I have a device that's able to connect to WiFi and talk to a server that I have. The overall goal is to have the device be able to authenticate a user while offline using signed access file of two levels. When a connection is requested, if the device detects its RTC to be out of date or compromised, it attempts to connect to WiFi, the my server to obtain a signed Timestamp (also contains some noise). If it can't connect to the server, it prompts the user for valid wifi credentials. The devices contain the public Root OEM key in their program memory (later implementations may use a permanent data chip and a secure EC crypto chip) that they use to verify access 1, which contains another public key, the intermediate key, along with some parameters like expiration, permissions, and noise signed by the OEM key. Access 2 is signed by the intermediate key, and is formatted the same except contains the connecting user's public key....

Men

4/4/2025

How to create categories and subcategories correctly ?

I wanted to put some help since I'm new to programming, maybe someone could share links to the guide

2ndchar

4/4/2025

leetcode like problem? optimization of nesting tags

i made a program to make text look spooky in html which is achieved by randomly applying a style tag to every single character however, the problem is that it really quickly balloons in character count and that's a problem for me...

SidKid

4/4/2025

how does one kill threads in Java? (I am unable to find something that works for Java 23)

all the ones I can find are deprecated

zeto

4/3/2025

Can't run Jar file Error: JavaFX runtime components are missing

So I'm trying to build an artifact of my JavaFX program but when i try to run the jar file I keep getting Error: JavaFX runtime components are missing, and are required to run this application Not sure what I'm missing here....

kkeiiii

4/3/2025

centralising column header

Heys guys can someone tell my why this isnt centralised and how i can centralise it

Peter Rader

4/3/2025

Push programatically

I need to push foobar.txt programatically. How to do that? This is my approach: ```package b; import java.io.File; import java.io.IOException; import java.net.InetSocketAddress; import org.apache.commons.exec.*;...

kathir💛

4/3/2025

roadmap to learn Java

I need the java roadmap to learn java for beginning level.

dans132

4/2/2025

Help with Java Crazy Eights Game(GUI)

I have the offline version implemented but im having difficulties getting the online version of the game to work . I need to be able to player 2,3 or 4 player online by me being client or server

Shruti

4/1/2025

Issue: API Returning Empty JSON Objects {}

facing an issue in my Spring Boot project. My API for fetching products is returning empty objects: [{}, {}, {}, {}] But I have verified that data exists in my H2 database.

Balsa

4/1/2025

Looking for guidance and help.

Hello folks, I am just looking for guidance how to solve this task. I know it's easy, so please consider I am a beginner here. 🙂 1. Create a program that allows input of student data. For each student, the following information is known: name and surname, index number, and a list of subjects. For each student in specialist studies, the same data as for a regular student should be known (implemented using inheritance), along with the name of the specialization. The maximum number of subjects for regular studies is 30, and for specialist studies is 10. Enable the display of all data for both types of students....

sean💤

4/1/2025

Game exited code 1

Hi how can i fix game exited with code 1 this happened afternoon I couldn't know how to fix this🥲

genji

3/30/2025

I am finding client

I am senior fullstack develoepr I can develop perfect all porject...

durandalAI

3/30/2025

Connection problem keycloak - java app within docker

Hi there, I am having some problems trying to connect my keycloak - java app using docker, first I face the problem of having referenced in my properties the keycloak container (http keycloak:8080/auth) and my browser was not able to resolve that URI, that was fixed using KEYCLOAK_FRONTEND_URL to change the requests to localhost:8012/auth, however now I am facing the problem to trying to log out from my app , I try the option backchannel logout url setting it to keycloak:8080 but still not work...

Franscis123$#

3/30/2025

Searching DB registers by other field instead PK using JPA

I have a project using JPA without any framework. I want to search registers by others fields like 'username', 'password' instead the primary key. I need to use SQL with JPA to it? ``` public User findUser(Long id) {...

AngelOfCreation

3/30/2025

Mendelian genetics in Forge 1.20.1

I need to create a framework called GeneticMob as a mixin to Animal.class in Forge 1.20.1. I then want to create mixins for individual animals that extend GeneticMob. An example would be PigMixin that extends GeneticMob. GeneticMob should provide common methods like getMainGene, getHiddenGene, etc. But these classes rely on enums called Gene that are specific to each animal. Is there a way for me to tell GeneticMob that there will be an enum called Gene so the compiler will let me work with it before its created? My overall idea is to create a system that lets me easily give other mobs mendelian genetics like the Panda has. If there is a better way of doing this I'm all ears....

Glenn-Thomas

3/30/2025

Java newbie (1 year). Im trying to write a chat app in java..

Im using JPQL and PostgreSQL. Im having problems with the mapping, it worked okay before, but after i used copilot on it, it broke... Could anyone help me please? code: https://github.com/h679172/chatapp.git Thank you...

CapitanTortugaYT

3/30/2025

Java/Processing PacMan

I'm making my own pacman for a class project, but I can't get the enemies to follow the player correctly

message.txt

Previous Next

Gaming

Programming

Java Community | Help. Code. Learn.

We are a Community full of Java developers. You can come here to connect other devs, get help, help others and do many more things!

Java Community | Help. Code. Learn.

We are a Community full of Java developers. You can come here to connect other devs, get help, help others and do many more things!