Hi HN,

I built an open-source Java SDK for building Model Context Protocol servers:

https://github.com/6000fish/mcp-java

It is intended for Java developers who want to expose tools, resources, or prompts to MCP-compatible agents without implementing the protocol plumbing from scratch.

The project includes:

• Core MCP server SDK
• stdio transport
• SSE transport
• Java API and annotation-based tool registration
• Spring Boot starter
• 5-minute quick-start example
• Copyable custom server template
• Ready-to-use MySQL and Redis MCP servers

The SDK is available on Maven Central:

<dependency>
    <groupId>io.github.6000fish</groupId>
    <artifactId>mcp-sdk</artifactId>
    <version>0.1.1</version>
</dependency>

<dependency>
    <groupId>io.github.6000fish</groupId>
    <artifactId>mcp-spring-boot-starter</artifactId>
    <version>0.1.1</version>
</dependency>

The MySQL and Redis servers are local stdio MCP servers, because database/cache connectors are usually safer to run inside the user's own environment instead of exposing credentials to a hosted remote endpoint.

GitHub:

https://github.com/6000fish/mcp-java

Release:

https://github.com/6000fish/mcp-java/releases/tag/v0.1.1

Feedback is welcome.