Discover 5 High-Quality Java Open‑Source Projects to Boost Your Development

Jeepay: Open‑Source Payment System

A complete payment solution for internet businesses, offering transaction, refund, transfer, and split‑payment capabilities, with support for service‑provider and regular merchant interfaces.

Integrated with WeChat Pay, Alipay, Cloud QuickPass, JD Pay, Shengfutong, and Agricultural Bank APIs, plus aggregate QR‑code payments.

Backend built on Spring Boot, Spring Security, MySQL; frontend uses Ant Design Vue; supports distributed deployment and high concurrency.

System Architecture

Payment Flow Diagram

Demo Screenshots

document-sharing-site: Online Document Retrieval & Preview

An open‑source platform that stores and previews virtually any document type (Word, Excel, PPT, PDF, images, etc.) and enables sharing.

Backend powered by Spring Boot, Hutool, Apache Tika, Elasticsearch, and JWT.

Frontend built with Vue and axios.

Demo Screenshots

asyncTool: Parallel Execution Framework

An open‑source multithreading utility library from JD, heavily leveraging

CompletableFuture

to handle arbitrary parallel, sequential, blocking, dependent, and callback‑based workflows, allowing flexible composition of thread execution order with full‑chain result callbacks.

The framework is currently stress‑tested in JD’s app backend under high‑concurrency, massive‑user scenarios.

Helidon: Java Library for Building Microservices

A collection of lightweight Java libraries for creating microservices that run on a fast Netty‑based web core. It is small, fast, and enjoyable to use.

Helidon embraces cloud‑native principles and fully supports GraalVM Native Image.

AgileBoot-Back-End: Rapid Development Scaffold

A heavily refactored and optimized rapid‑development framework based on Ruoyi, addressing issues such as chaotic naming, disorganized packaging, and excessive custom utilities lacking unit‑test coverage.

Backend built with Spring Boot, Spring Security, Redis, MyBatis Plus, and MySQL.

Frontend uses Vue 3 and Element UI.

Refactoring Highlights

Demo Screenshots

Further Reading

Nginx Visualisation Tool – One‑Click Config Generation and Monitoring

SpringBoot Annotation Cheat Sheet – Master It in One Week

Declarative HTTP Client Plugin for IDEA – Powerful and Easy

Elegant API Interface Code Samples

Best Diagramming Tools for Developers

DevOps Automation Deployment Tool – A Must‑Try

Mall Project – Full‑Stack E‑Commerce Tutorial Upgrade

Mall Open‑Source E‑Commerce Project – 40K+ Stars