Stream Processing and Complex Event Processing Engine
Examples, server integrations for generating Swagger API Specification
BotCity Framework - Open Source RPA
Free implementation of Play Services
The OWASP ZAP core project
Most popular Mocking framework for unit tests written in Java
Magic Another Game Engine
Application Performance Monitoring System
iText for Java represents the next level of SDKs for developers
Stanford CoreNLP, a Java suite of core NLP tools
An extensible request/response workbench
PSLab Android App
Native Operating System and Hardware Information
Hibernate's core object/relational mapping functionality
Main Liquibase Source
Apache Lucene open-source search software
Java implementation of RSocket
Simplified version of ZXing, optimized to scan codes to generate QR
Pure Java annotation, single class file, rapid development
Clean object-oriented & layered architecture
Capturing JVM and application-level metrics
Red5 Server core
Open source alternative to Auth0 / Firebase Auth, etc.
A library for working with Bitcoin
A lightweight flexible development framework