Top 30 Must‑Watch Java Open‑Source Projects for 2025

Top 30 Java Open‑Source Projects (2025)

spring-projects/spring-boot (GitHub) – 72k+ stars – Java microservice standard framework that simplifies Spring application development and deployment.

jeecgboot/jeecgboot (GitHub / Gitee) – 44k+ (Gitee 50k+) stars – AI low‑code platform, supports large‑model integration and one‑click front‑back‑end generation, widely adopted by domestic enterprises.

apache/dubbo (GitHub / Gitee) – 42k+ / 18k+ stars – High‑performance RPC framework, core component of microservice governance and the foundation of Alibaba’s tech stack.

dromara/hutool (Gitee) – 35k+ stars – Java utility library “Swiss army knife”, covering encryption, IO, HTTP, date and other common functions.

alibaba/nacos (GitHub / Gitee) – 32k+ / 20k+ stars – Dynamic service discovery, configuration management and service governance platform, core of Spring Cloud Alibaba.

baomidou/mybatis-plus (Gitee) – 25k+ stars – MyBatis enhancement tool, non‑intrusive CRUD that greatly improves database operation efficiency.

elastic/elasticsearch (GitHub) – 68k+ stars – Distributed search and analytics engine, supporting log, monitoring, recommendation‑system scenarios.

alibaba/Sentinel (GitHub / Gitee) – 22k+ / 22k+ stars – Traffic‑control, circuit‑breaking and system‑load protection component, ensuring microservice stability.

kestra-io/kestra (GitHub) – 23.8k stars – General workflow orchestration platform, offering 800+ plugins for data, AI and infrastructure automation.

SnailClimb/JavaGuide (Gitee) – 150k+ stars – Most popular Java learning and interview guide, non‑framework but highly influential.

macrozheng/mall (Gitee) – 70k+ stars – Full‑stack e‑commerce system example (Spring Boot + Vue), suitable for learning and secondary development.

redisson/redisson (GitHub) – 24k+ stars – Advanced Java client for Redis, providing distributed locks, collections, queues and more.

apache/flink (GitHub) – 28k+ stars – Unified batch‑stream big‑data processing engine, preferred for real‑time computing, written in Java/Scala.

quarkusio/quarkus (GitHub) – 18k+ stars – Cloud‑native Java framework with fast startup and low memory, targeting GraalVM and Kubernetes.

keycloak/keycloak (GitHub) – 31k+ stars – Open‑source identity and access management platform, supporting OAuth2, OIDC and SAML.

testcontainers/testcontainers-java (GitHub) – 8.5k+ stars – JUnit testing tool that automatically starts/stops Docker containers, improving integration‑test reliability.

AutoMQ/automq (GitHub) – 7.8k+ stars – S3‑based disk‑less Kafka implementation, low cost, high availability, suitable for cloud‑native scenarios.

alibaba/spring-ai-alibaba (GitHub) – 7.0k+ stars – Agentic AI framework for Java developers, seamless integration of large models such as Tongyi Qianwen.

apache/camel (GitHub) – 6.5k+ stars – Enterprise Integration Patterns implementation, supporting 300+ components connecting various systems.

dromara/Sa-Token (Gitee) – 48k+ stars – Lightweight Java permission authentication framework, supporting login, SSO, OAuth2 and microservice authorization.

sharding-sphere/shardingsphere (GitHub / Gitee) – 18k+ / 15k+ stars – Distributed database middleware, supporting sharding, read/write splitting and elastic scaling.

micrometer-metrics/micrometer (GitHub) – 4.5k+ stars – Application metrics collection library, integrates seamlessly with Prometheus, Datadog and others.

Mindustry (GitHub) – 25.7k+ stars – Automated tower‑defense game, showcases Java capabilities in high‑performance graphics and logic processing.

camunda/camunda-bpm-platform (GitHub) – 3.9k+ stars – Open‑source BPMN workflow engine, supports business‑process modeling and execution.

modelcontextprotocol/java-sdk (GitHub) – 2.9k+ stars – Official Java SDK for Model Context Protocol, standardizing LLM context interaction.

fay (xszyou/fay) (Gitee) – 1.7k+ stars – Digital‑human / MCP framework, integrates LLMs with business systems, supports voice, dialogue and execution.

jeelowcode/JeeLowCode (Gitee) – 9.1k+ stars – Enterprise‑grade low‑code platform, drag‑and‑drop development with domestic adaptation.

alibaba/COLA (GitHub / Gitee) – 12k+ stars – Clean Object‑oriented and Layered Architecture, Alibaba’s application architecture template.

2025 Java Open‑Source Ecosystem Trends

1. AI Deep Integration

Projects such as Spring AI Alibaba, LangChat, Fay and Model Context Protocol demonstrate that Java is accelerating its adoption of large‑model AI and AI agents, moving from simple API calls to building intelligent agents for enterprise‑grade applications.

2. Low‑Code & Productivity Tools Explosion

JeecgBoot, JeeLowCode, Hutool and MyBatis‑Plus continue to attract high attention, reflecting developers’ relentless pursuit of development efficiency.

3. Cloud‑Native & Observability Maturity

Quarkus, Micrometer, Testcontainers and AutoMQ underpin Java’s competitiveness in Kubernetes, serverless and observability scenarios.

4. Domestic Ecosystem Flourishing

On Gitee, projects like Hutool, Sa‑Token, JeecgBoot and LangChat form a complete domestic technology stack, meeting the needs of trusted‑computing, government and financial sectors.

5. Microservice Governance Stabilizes

Nacos, Sentinel, Dubbo and ShardingSphere have become enterprise standards; innovation now shifts toward intelligent operations and AI‑assisted governance.