Current implementation of HttpServletStreamableServerTransportProvider or HttpServletSseServerTransportProvider needs strict stickyness

[olamy]

Current implementations are holding mcp sessions into a in memory Map

java-sdk/mcp/src/main/java/io/modelcontextprotocol/server/transport/HttpServletStreamableServerTransportProvider.java

Line 108 in 713ee1a

private final ConcurrentHashMap<String, McpStreamableServerSession> sessions = new ConcurrentHashMap<>();

This make it mandatory to have strict stickyness "a la" browser" in a replicated/high availability environement which doesn't exist for agent (and we cannot rely on llm agents to implement this)
The feature could be

• first very simple option an option for HttpServletStreamableServerTransportProvider.Builder to have an option to provide the map (then users can use different tools to have some shared Map)
• create an interface to handle those sessions (with minimum operations such add, get. delete)

[olamy]

just put a rough idea for this here #500