Free universal database tool and SQL client

RxJava – Reactive Extensions for the JVM – a library for composing asynchronous and event-based programs using observable sequences for the Java VM.

Alibaba Java Diagnostic Tool Arthas/Alibaba Java诊断利器Arthas

Netty project - an event-driven asynchronous network application framework

ZXing ("Zebra Crossing") barcode scanning library for Java, Android

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

JDK main-line development https://openjdk.org/projects/jdk

Zipkin is a distributed tracing system

A Java 8+ Jar & Android APK Reverse Engineering Suite (Decompiler, Editor, Debugger & More)

Cryptomator for Windows, macOS, and Linux: Secure client-side encryption for your cloud storage, ensuring privacy and control over your data.

Logstash - transport and process your logs, events, or other data

Vert.x is a tool-kit for building reactive applications on the JVM

Access your entire server infrastructure from your local desktop

Very spicy additions to the Java programming language.

Generate diagrams from textual description

OpenRefine is a free, open source power tool for working with messy data and improving it

jsoup: the Java HTML parser, built for HTML editing, cleaning, scraping, and XSS safety.

Resilience4j is a fault tolerance library designed for Java8 and functional programming

A collection of source code generators for Java.

Feign makes writing java http clients easier

A simple expressive web framework for java. Spark has a kotlin DSL https://github.com/perwendel/spark-kotlin

Flyway by Redgate • Database Migrations Made Easy.

A Camera component for React Native. Also supports barcode scanning!

Java JsonPath implementation

A compact and highly efficient workflow and Business Process Management (BPM) platform for developers, system admins and business users.

Test Automation Made Simple

Tsunami is a general purpose network security scanner with an extensible plugin system for detecting high severity vulnerabilities with high confidence.

GoCD - Continuous Delivery server main repository

A tool for mocking HTTP services

Catch common Java mistakes as compile-time errors