Real Java in the browser, built from OpenJDK. Issues and examples for CheerpJ: Java 8, 11, 17 and 21 apps, applets, JNLP and libraries, client-side.

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• Updated Nov 2, 2026

Eclipse Collections Katas

java katas eclipse-collections java-11 java-17 code-katas java-21

• Updated Mar 31, 2026
• Java

Code Kata collection for JVM Languages and Libraries.

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• Updated Nov 2, 2026
• Java

Exploring Java new features from 8 to 28

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• Updated Oct 24, 2026
• Java

A desktop image editor

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• Updated Nov 7, 2026
• Java

RealWorld backend API built using Java 21 and Spring Boot 3

h2-database jpa-hibernate java-21 spring-boot-3-2

• Updated Sep 18, 2025
• Java

Modern way of optimizing garbage collection in Minecraft: Java Edition

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• Updated Oct 29, 2026

An advanced fishing plugin based on MoreFish, created 2 years after its last update.

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• Updated Nov 12, 2026
• Java

Actor4j’s core implementation separates SDK and runtime, enabling flexible execution models.

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• Updated Nov 12, 2026
• Java

⚡ Ultra-Low Latency Continuous Double Auction Matching Engine in Java 21 Loom. In-memory L2 market depth, price-time priority, STOMP WebSockets, 50k+ ops/sec.

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• Updated Nov 11, 2026
• Java

⚡ In-Memory Vector Search Engine & HNSW ANN Graph in Java 21 Loom. Sub-millisecond KNN retrieval, 8-bit scalar quantization (SQ8), 16,000+ QPS.

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• Updated Nov 12, 2026
• Java

🇮🇳 High-Performance Geospatial Administrative Hierarchy & Proximity Query Engine for India's 650k+ Census Settlements (Java 21 Loom, 2D KD-Tree, 38k+ QPS).

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• Updated Nov 12, 2026
• Java

Modern Selenium framework

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• Updated Nov 11, 2026
• Java

Java 9-28 Hackery, destroys module system + reflection filters

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• Updated Aug 25, 2026
• Java

A homestay booking system like Airbnb. The guideline of a personal project for applying to your CV/resume.

java docker redis spring-boot postgresql postgis-extension java-21

• Updated Feb 5, 2025
• Java

Fast dual-era framework-agnostic Model Context Protocol (MCP) runtime for Java and Kotlin. Streamable HTTP, native Netty transports, tools, tasks, resources, prompts, completions, skills over MCP, stateless and stateful with resumable session support.

java ai server netty mcp ai-agents java-21 llm-tools ai-agent-tools model-context-protocol java-25 ai-agents-mcp java-27

• Updated Nov 12, 2026
• Java

Lightweight Java library to interact with the OpenAI API (GPT, DALL-E, TTS, etc.)

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• Updated Mar 9, 2026
• Java

A Spring Boot application for tracking flight events.

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• Updated May 8, 2025
• Java

A lambda factory.

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• Updated Jun 19, 2026
• Java

AI-powered SaaS translation platform for web novels — batch translate with RAG memory, multi-agent collaboration, Stripe billing, Chrome extension & REST API. Java 21 + React 19 + Python.

react chrome-extension translation spring-boot stripe saas multi-agent openai web-novel rag vector-search redis-stack java-21

• Updated Jun 3, 2026
• Java