Top 12 Must‑Know Java Open‑Source Projects for 2023

Here are the 12 most popular Java open‑source projects on GitHub in May 2023, listed with their repository URLs, star counts and a brief description.

shenyu – https://github.com/dromara/shenyu (Star 4664). An extensible, high‑performance, reactive API gateway for all micro‑service scenarios.

java-design-patterns – https://github.com/iluwatar/java-design-patterns (Star 67279). A comprehensive collection of design patterns in Java, illustrating best practices for solving common software design problems.

pulsar – https://github.com/apache/pulsar (Star 8707). Apache Pulsar is a cloud‑native distributed messaging platform that integrates messaging, storage, and lightweight compute.

leetcode – https://github.com/doocs/leetcode (Star 5298). Repository of solutions for LeetCode, "剑指 Offer", and "程序员面试金典" in multiple languages such as Java, Python, C++, JavaScript, C# and Go.

airbyte – https://github.com/airbytehq/airbyte (Star 2942). An open‑source data integration platform that syncs data from applications, APIs, and databases to warehouses.

APIJSON – https://github.com/Tencent/APIJSON (Star 10972). A JSON‑based API protocol and ORM library that automates CRUD, complex queries, and transactions, reducing development and communication costs.

TheAlgorithms/Java – https://github.com/TheAlgorithms/Java (Star 37797). A repository containing Java implementations of a wide range of algorithms.

-- – https://github.com/981011512/-- (Star 3147). A complete parking‑lot management system built with Java, Spring Boot, OAuth2, MySQL/MongoDB/Redis, Netty, and a Vue‑TypeScript admin template.

SpringAll – https://github.com/wuyouzhuguli/SpringAll (Star 20443). Source code collection for a personal blog, covering Spring Boot, Spring Cloud, Shiro, Spring Security, and OAuth2.

JimuReport – https://github.com/zhangdaiscott/JimuReport (Star 2000). A free data‑visualization tool for designing reports and dashboards with an Excel‑like drag‑and‑drop interface.

java-tron – https://github.com/tronprotocol/java-tron (Star 2689). Java implementation of the TRON blockchain protocol.

keycloak – https://github.com/keycloak/keycloak (Star 8981). An open‑source identity and access management solution for securing applications and services.