Java MCP Server SDK lets developers skip JSON-RPC boilerplate

6000fish released `mcp-java` v0.1.1, an open-source Java SDK designed to let Java developers quickly build custom MCP (Model Context Protocol) Servers for use with AI agents and tools such as Claude, Cursor, and Codex. The motivation was a gap in the ecosystem: most MCP Server examples and tooling are written for Node.js or Python, making it harder for Java developers to expose their own business systems, databases, or Spring Boot services to agents via the unified MCP protocol.

`mcp-examples` provides a quick-start, a custom-server-template, and a Spring Boot example.

The project is structured into four main modules. `mcp-sdk` is the core library, supporting stdio and SSE transports, Java API-based registration of tools, resources, and prompts, and an annotation-driven model where a `@McpServer` class with `@McpTool`-annotated methods is scanned at startup and exposed automatically — no manual JSON-RPC handling required. `mcp-spring-boot-starter` wraps this for Spring Boot projects. `mcp-examples` provides a quick-start, a custom-server-template, and a Spring Boot example. The `mcp-server-collection` includes two ready-to-use servers: a MySQL MCP Server exposing tools such as `query(sql)`, `list_tables()`, and `describe_table()` with security restrictions that block DELETE, DROP, ALTER, TRUNCATE, and multi-statement SQL; and a Redis MCP Server covering key/value, hash, list, set, metadata, and diagnostics operations with destructive deletes disabled by default.

Both ready-to-use servers are designed for local stdio deployment rather than remote endpoints, with the post explaining that running the server on the same machine or internal network as the database avoids exposing credentials or database ports to the public internet. The MySQL and Redis servers have also been listed on MCP.so. All artifacts are available on Maven Central at version `0.1.1`, and the source is hosted on both GitHub (`6000fish/mcp-java`) and Gitee.

Key facts

1. 01Author 6000fish open-sourced `mcp-java` v0.1.1, a Java SDK for building MCP Servers, hosted on GitHub at `6000fish/mcp-java`.
2. 02The SDK supports stdio and SSE transports and offers annotation-based tool registration via `@McpServer` and `@McpTool`, eliminating manual JSON-RPC coding.
3. 03A `mcp-spring-boot-starter` module is included for integrating MCP Server capabilities into existing Spring Boot projects.
4. 04Ready-to-use MySQL and Redis MCP Servers are bundled; the MySQL server blocks DELETE, DROP, ALTER, TRUNCATE, and multi-statement SQL for safety.
5. 05The Redis MCP Server disables destructive deletes by default and limits broad key-pattern and bulk collection reads.
6. 06Both the core SDK and Spring Boot starter are published to Maven Central under group `io.github.6000fish` at version `0.1.1`.
7. 07The MySQL and Redis servers are intentionally scoped to local stdio use to avoid exposing database credentials or ports to the public internet.

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