chore: Extract DefaultMcpServerSessionFactory from McpAsyncServer.

Signed-off-by: He-Pin <[email protected]>

Author: He-Pin

mcp/src/main/java/io/modelcontextprotocol/server/McpAsyncServer.java

@@ -4,47 +4,25 @@
 
 package io.modelcontextprotocol.server;
 
-import java.time.Duration;
-import java.util.ArrayList;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
-import java.util.Optional;
-import java.util.UUID;
-import java.util.concurrent.ConcurrentHashMap;
-import java.util.concurrent.CopyOnWriteArrayList;
-import java.util.function.BiFunction;
-
-import io.modelcontextprotocol.spec.DefaultMcpStreamableServerSessionFactory;
-import io.modelcontextprotocol.spec.McpServerTransportProviderBase;
-import io.modelcontextprotocol.spec.McpStreamableServerTransportProvider;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
 import com.fasterxml.jackson.core.type.TypeReference;
 import com.fasterxml.jackson.databind.ObjectMapper;
-
-import io.modelcontextprotocol.spec.JsonSchemaValidator;
-import io.modelcontextprotocol.spec.McpClientSession;
-import io.modelcontextprotocol.spec.McpError;
-import io.modelcontextprotocol.spec.McpSchema;
-import io.modelcontextprotocol.spec.McpSchema.CallToolResult;
-import io.modelcontextprotocol.spec.McpSchema.JSONRPCResponse;
-import io.modelcontextprotocol.spec.McpSchema.LoggingLevel;
-import io.modelcontextprotocol.spec.McpSchema.LoggingMessageNotification;
-import io.modelcontextprotocol.spec.McpSchema.ResourceTemplate;
-import io.modelcontextprotocol.spec.McpSchema.SetLevelRequest;
-import io.modelcontextprotocol.spec.McpSchema.TextContent;
-import io.modelcontextprotocol.spec.McpSchema.Tool;
-import io.modelcontextprotocol.spec.McpServerSession;
-import io.modelcontextprotocol.spec.McpServerTransportProvider;
+import io.modelcontextprotocol.spec.*;
+import io.modelcontextprotocol.spec.McpSchema.*;
 import io.modelcontextprotocol.util.Assert;
 import io.modelcontextprotocol.util.DeafaultMcpUriTemplateManagerFactory;
 import io.modelcontextprotocol.util.McpUriTemplateManagerFactory;
 import io.modelcontextprotocol.util.Utils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 import reactor.core.publisher.Flux;
 import reactor.core.publisher.Mono;
 
+import java.time.Duration;
+import java.util.*;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.CopyOnWriteArrayList;
+import java.util.function.BiFunction;
+
 /**
  * The Model Context Protocol (MCP) server implementation that provides asynchronous
  * communication using Project Reactor's Mono and Flux types.
@@ -148,9 +126,8 @@ public class McpAsyncServer {
 		Map<String, McpNotificationHandler> notificationHandlers = prepareNotificationHandlers(features);
 
 		this.protocolVersions = mcpTransportProvider.protocolVersions();
-
-		mcpTransportProvider.setSessionFactory(transport -> new McpServerSession(UUID.randomUUID().toString(),
-				requestTimeout, transport, this::asyncInitializeRequestHandler, requestHandlers, notificationHandlers));
+		mcpTransportProvider.setSessionFactory(new DefaultMcpServerSessionFactory(requestTimeout,
+				this::asyncInitializeRequestHandler, requestHandlers, notificationHandlers));
 	}
 
 	McpAsyncServer(McpStreamableServerTransportProvider mcpTransportProvider, ObjectMapper objectMapper,

mcp/src/main/java/io/modelcontextprotocol/spec/DefaultMcpServerSessionFactory.java

@@ -0,0 +1,50 @@
+package io.modelcontextprotocol.spec;
+
+import io.modelcontextprotocol.server.McpInitRequestHandler;
+import io.modelcontextprotocol.server.McpNotificationHandler;
+import io.modelcontextprotocol.server.McpRequestHandler;
+
+import java.time.Duration;
+import java.util.Map;
+
+/**
+ * The default implementation of {@link McpServerSession.Factory}.
+ *
+ * @author He-Pin
+ */
+public class DefaultMcpServerSessionFactory implements McpServerSession.Factory {
+
+	Duration requestTimeout;
+
+	McpInitRequestHandler initHandler;
+
+	Map<String, McpRequestHandler<?>> requestHandlers;
+
+	Map<String, McpNotificationHandler> notificationHandlers;
+
+	public DefaultMcpServerSessionFactory(final Duration requestTimeout, final McpInitRequestHandler initHandler,
+			final Map<String, McpRequestHandler<?>> requestHandlers,
+			final Map<String, McpNotificationHandler> notificationHandlers) {
+		this.requestTimeout = requestTimeout;
+		this.initHandler = initHandler;
+		this.requestHandlers = requestHandlers;
+		this.notificationHandlers = notificationHandlers;
+	}
+
+	@Override
+	public McpServerSession create(final McpServerTransport sessionTransport) {
+		final String sessionId = generateSessionId(sessionTransport);
+		return new McpServerSession(sessionId, requestTimeout, sessionTransport, initHandler, requestHandlers,
+				notificationHandlers);
+	}
+
+	/**
+	 * Generate a unique session ID for the given transport.
+	 * @param sessionTransport the transport
+	 * @return unique session ID
+	 */
+	protected String generateSessionId(final McpServerTransport sessionTransport) {
+		return java.util.UUID.randomUUID().toString();
+	}
+
+}