Introduces a new Server-Sent Events (SSE) Server transport implementation
based on the Servlet API that enables MCP integration with any Java HTTP
server application supporting Servlets.
This implementation complements the existing WebFlux and WebMvc transports
by providing a generic Servlet-based option that works with any Java web
server, not just Spring applications.
Key changes:
- Add HttpServletSseServerTransport with async Servlet 6.0 support
- Add integration tests with embedded Tomcat
- Add servlet dependencies with externalized versions:
- jakarta.servlet-api 6.1.0 (provided)
- tomcat-embed-core 11.0.2 (test)
- tomcat-embed-websocket 11.0.2 (test)
Resolves#61
Split the transport implementations into dedicated modules to improve modularity
and reduce core dependencies.
Added shared test module for common test utilities.
Key changes:
- Create mcp-transport/mcp-webflux-sse-transport module
- Move SseClientTransport → WebFluxSseClientTransport
- Move SseServerTransport → WebFluxSseServerTransport
- Move related tests and utilities
- Create mcp-transport/mcp-webmvc-sse-transport module
- Add new WebMvcSseServerTransport implementation
- Add corresponding tests and integration tests
- Add framework-independent SSE client implementations to core module
- Add FlowSseClient using java.net.http
- Add HttpClientSseClientTransport using java.net.http
- Keep StdioClientTransport/StdioServerTransport in core (no external deps)
- Create mcp-test module for shared test infrastructure
- Move abstract test base classes
- Move shared test utilities and mocks
- Update test dependencies
The modular approach allows users to choose between:
- Framework-specific implementations (WebFlux/WebMVC)
- Pure Java implementations (java.net.http)
- Basic implementations (STDIO)
Add breaking changes readme: 0.5.0-BREAKING-CHANGES.md
Resolves#54
Move Logback dependency to test scope to make it possible for applications using this library to choose their implementation of the SLF4J API. For example, Spring Boot provides one out of the box already.
Fixes gh-49
Signed-off-by: Thomas Vitale <ThomasVitale@users.noreply.github.com>
- Implement MCP server with async/sync support and builder pattern configuration
- Add Server stdio/SSE transport layers with robust error handling
- Convert McpClient and McpServer to interfaces for better extensibility
- Add sampling capabilities for LLM interactions (text/image)
- Implement dynamic root management and runtime tool management
- Add comprehensive prompt and resource capabilities
- Add support for dynamic root management (add/remove roots at runtime)
Architecture Changes
- Introduce registration records for tools, resources, and prompts
- Improve thread safety with concurrent collections
- Enhance resource template handling
- Implement builder patterns for Server/Client capabilities
- Add support for server capabilities and implementation info
Transport Layer:
- Implement SseServerTransport with SSE endpoints
- Add StdioServerTransport for process-based communication
- Reorganize transport packages for better organization
- Improve transport error handling and shutdown processes
Documentation:
- Add detailed MCP reference documentation
- Include architecture diagrams and API documentation
- Add comprehensive test coverage for all components
- Include sample projects demonstrating stdio/SSE transports
BREAKING CHANGES:
Transport Package Reorganization
- Move StdioClientTransport to o.s.ai.mcp.client.transport
- Move SseClientTransport to o.s.ai.mcp.client.transport
- Move ServerParameters to o.s.ai.mcp.client.transport
- StdioClientTransport.errorHandler changed to private with
setter method Migration: Use setErrorHandler() method
instead of direct field access
API Changes
- Replace static factory methods with builder pattern
- Update ServerCapabilities to use builder pattern
- Make StdioClientTransport.errorHandler private with setter
- Replace rootsListProvider with direct root management
- Remove deprecated static factory methods
Resolves #27,#25,#24,#11
Related to #12
- Rename DefaultMcpTransport to AbstractMcpTransport and make it abstract
- Add graceful shutdown support via closeGracefully() method
- Enhance McpTransport interface with default close() implementation
- Improve documentation across transport layer classes