Java HacktoberFest

Open-source Java projects categorized as HacktoberFest

Top 23 Java HacktoberFest Projects

  • Design Patterns

    Design patterns implemented in Java

    Project mention: Are there any quick videos/articles/resources that go over stuff not explicit taught in University? | | 2023-01-30

    Java Design Patterns

  • Java

    All Algorithms implemented in Java

    Project mention: Cool Github repositories for Everyone | | 2022-12-29
  • Sonar

    Write Clean Java Code. Always.. Sonar helps you commit clean code every time. With over 600 unique rules to find Java bugs, code smells & vulnerabilities, Sonar finds the issues while you focus on the work.

  • JHipster

    JHipster, much like Spring initializr, is a generator to create a boilerplate backend application, but also with an integrated front end implementation in React, Vue or Angular. In their own words, it "Is a development platform to quickly generate, develop, & deploy modern web applications & microservice architectures."

    Project mention: Micro Frontends for Java Microservices | | 2023-01-20

    exports.onExecutePostLogin = async (event, api) => { const namespace = ''; if (event.authorization) { api.idToken.setCustomClaim('preferred_username',; api.idToken.setCustomClaim(`${namespace}/roles`, event.authorization.roles); api.accessToken.setCustomClaim(`${namespace}/roles`, event.authorization.roles); } }

  • Jenkins

    Jenkins automation server

    Project mention: CI/CD #03. Jenkins: using Pipeline and proper Bash script to run Pytest. | | 2023-02-05

    To recap, I am running Jenkins 2.388 LTS on my Ubuntu 22.10, the name of this machine is HP-Pavilion-15. I am accessing Jenkins and HP-Pavilion-15 from my Windows 10 machine using FireFox and ssh, respectively. And Pipeline is the Jenkins documentation page which I have been working through.

  • termux-app

    Termux - a terminal emulator application for Android OS extendible by variety of packages.

    Project mention: Python package Pandas can not install · Issue #3048 · termux/termux-app · GitHub | | 2023-02-08
  • Apache RocketMQ

    Apache RocketMQ is a cloud native messaging and streaming platform, making it simple to build event-driven applications.

    Project mention: Storage Enhancements for Apache RocketMQ 5.0 in Stream Scenarios | | 2022-12-15

    Join the Apache RocketMQ community:

  • shardingsphere

    Ecosystem to transform any database into a distributed database system, and enhance it with sharding, elastic scaling, encryption features & more

    Project mention: ShardingSphere 5.3.0 is released: new features and improvements | | 2022-12-11

    🔗 Release Notes

  • InfluxDB

    Build time-series-based applications quickly and at scale.. InfluxDB is the Time Series Platform where developers build real-time applications for analytics, IoT and cloud-native services. Easy to start, it is available in the cloud or on-premises.

  • openapi-generator

    OpenAPI Generator allows generation of API client libraries (SDK generation), server stubs, documentation and configuration automatically given an OpenAPI Spec (v2, v3)

    Project mention: Swagger codegen or custom tool | | 2023-02-08
  • Quarkus

    Quarkus: Supersonic Subatomic Java.

    Project mention: 2023 will be when browsers will support GC-based languages in production. Both GC and Exception Handling are already available to various degrees. Being an early adopter could boost Scala's adoption by being one of the first but also the best language in the browser! | | 2023-02-02

    GraalVM's Native Image is pretty wonderful, and I'm sure it will end up supporting WASM; just like in the case of Scala Native, this will take some wind away from any other WASM effort; and speaking of optimizations, GraalVM has more resources to invest in an AOT compiler that can do optimizations ahead of time. And because of the “serverless” trend, the community has invested significant resources into native-image resources already. The existence of developments like Quarkus or Spring Boot 3 can only mean that build tools and libraries ready for Native Image will only get better.

  • Apache ZooKeeper

    Apache ZooKeeper

    Project mention: Analysing Github Stars - Extracting and analyzing data from Github using Apache NiFi®, Apache Kafka® and Apache Druid® | | 2023-01-11

    You can install Kafka from Because Druid and Kafka both use Apache Zookeeper, I opted to use the Zookeeper deployment that comes with Druid, so didn’t start it with Kafka. Once running, I created two topics for me to post the data into, and for Druid to ingest from:

  • Zed

    The OWASP ZAP core project

    Project mention: Pentesting Tools I Use Everyday | | 2023-02-07

    Learn more about ZAP here:

  • QuestDB

    An open source time-series database for fast ingest and SQL queries

    Project mention: any opinion good or bed about a code that smells? | | 2023-01-28

    The Java API implementation is problematic due to over allocating which results in a great deal of overhead. Projects like QuestDB don't use the Java API much to reduce GC thrashing. It results in a DB that outperforms C++ counterparts.

  • android-gif-drawable

    Views and Drawable for displaying animated GIFs on Android

  • Feign

    Feign makes writing java http clients easier

    Project mention: Spring Feign Client | | 2022-08-27

    The actual project for feign is OpenFeign . Spring comes with it's own starter . Add below dependency to the project

  • LSPosed

    LSPosed Framework

    Project mention: [Help] SafetyNet failing after weeks working fine | | 2023-02-08

    This shamiko

  • SuperTokens Community

    Open source alternative to Auth0 / Firebase Auth / AWS Cognito

    Project mention: I created Atomic: Self Hosted Open Source Alternative to Reclaim, Clockwise & Motion | | 2023-01-22
  • Paper

    High performance Spigot fork that aims to fix gameplay and mechanics inconsistencies

    Project mention: Minecraft server | | 2023-01-22

    Paper + Geyser will do the trick

  • Testcontainers

    Testcontainers is a Java library that supports JUnit tests, providing lightweight, throwaway instances of common databases, Selenium web browsers, or anything else that can run in a Docker container.

    Project mention: Spring Cloud Gateway 4.0.0-RC2 native example with Testcontainers | | 2022-12-08

    This repository provides a BuildImageTest that uses the buildpack to create a native image. It then tests the native image, using Testcontainers and JUnit. Building the native image with AOT processing, as part of a test, takes minutes not seconds, and should not be part of normal "inner loop" development. So the BuildImageTest is in a separate sourceSet and can be executed independently. This is a very powerful pattern, that I'm just getting started with. I would love to hear your thoughts on this pattern or other alternatives to it.

  • graylog

    Free and open source log management

    Project mention: Top 11 Splunk Alternatives that you may consider in 2023 | | 2023-02-06

    Graylog is an open-source centralized log management and analytics tool. It collects, enhances, correlates, searches, and visualizes all your log data in one location to uncover patterns and trends for application and IT infrastructure.

  • MinecraftForge

    Modifications to the Minecraft base files to assist in compatibility between mods.

    Project mention: Fluid API in 1.19.3 | | 2023-01-15

    I looked in LivingEntity and it looked to me like water movement physics are still hardcoded to affect all non-lava fluids in the travel function. is listed in the fluid API commit as the go-to source for info and it mentions a "fluid motion" setting but I don't see it. I get the feeling the documentation is outdated but that's literally the only documentation I can find anywhere about this api. Very frustrating.

  • Hazelcast

    Open-source distributed computation and storage platform. Real-time Stream Processing Unconference. Save Your Spot

    Project mention: Real-time stream processing with Hazelcast and Pulsar | | 2023-01-26

    Join the Hazelcast Slack andHazelcast Github repository.

  • EdXposed

    Elder driver Xposed Framework.

    Project mention: Intercept android app traffic in Burp Suite: From root to hack [ULTIMATE GUIDE for bug hunters] | | 2022-07-16

    Download the zip files from the redirected links for your android SDK version. also download this extra zip file from here.

  • Drools

    Drools is a rule engine, DMN engine and complex event processing (CEP) engine for Java.

    Project mention: SourceBuddy Brings Eval To Java | | 2023-01-25

    IMHO you're better off using something like for this. Non-devs writing code is a pipe-dream. It never works out.

  • SaaSHub

    SaaSHub - Software Alternatives and Reviews. SaaSHub helps you find the best software and product alternatives

NOTE: The open source projects on this list are ordered by number of github stars. The number of mentions indicates repo mentiontions in the last 12 Months or since we started tracking (Dec 2020). The latest post mention was on 2023-02-08.

Java HacktoberFest related posts


What are some of the best open-source HacktoberFest projects in Java? This list will help you:

Project Stars
1 Design Patterns 79,703
2 Java 50,156
3 JHipster 20,309
4 Jenkins 20,253
5 termux-app 19,066
6 Apache RocketMQ 18,680
7 shardingsphere 17,922
8 openapi-generator 15,151
9 Quarkus 11,306
10 Apache ZooKeeper 11,046
11 Zed 10,462
12 QuestDB 10,067
13 android-gif-drawable 9,283
14 Feign 8,598
15 LSPosed 8,526
16 SuperTokens Community 7,988
17 Paper 7,115
18 Testcontainers 6,761
19 graylog 6,410
20 MinecraftForge 5,971
21 Hazelcast 5,228
22 EdXposed 4,946
23 Drools 4,929
SaaSHub - Software Alternatives and Reviews
SaaSHub helps you find the best software and product alternatives