@startuml MCP Class Diagram

' Style configurations
skinparam class {
    BackgroundColor White
    ArrowColor Black
    BorderColor Black
}

' Interfaces
interface McpAsyncTransport {
    +start(): void
    +close(): void
    +setInboudMessageHandler(Consumer<JSONRPCMessage>): void
    +setErrorHandler(Consumer<String>): void
    +sendMessage(JSONRPCMessage): Mono<Void>
}

interface McpAsyncSession {
    +initialize(): Mono<InitializeResult>
    +close(): void
    +listTools(): Mono<ListToolsResult>
    +callTool(String, Map<String, Object>): Mono<CallToolResult>
    +createMessage(List<SamplingMessage>, ModelPreferences): Mono<CreateMessageResult>
}

interface McpClient {
    +initialize(): InitializeResult
    +listTools(): ListToolsResult
    +callTool(String, Map<String, Object>): CallToolResult
    +createMessage(List<SamplingMessage>, ModelPreferences): CreateMessageResult
}

' Classes
class DefaultMcpTransport {
    -objectMapper: ObjectMapper
    -errorSink: Sinks.Many<String>
    -inboundSink: Sinks.Many<JSONRPCMessage>
    -outboundSink: Sinks.Many<JSONRPCMessage>
    +DefaultMcpTransport()
    +DefaultMcpTransport(ObjectMapper)
}

class McpAsyncClient {
    -transport: McpAsyncTransport
    -session: McpAsyncSession
    +McpAsyncClient(McpAsyncTransport)
    +initialize(): Mono<InitializeResult>
    +close(): void
}

class McpSyncClient {
    -asyncClient: McpAsyncClient
    +McpSyncClient(McpAsyncTransport)
    +initialize(): InitializeResult
    +close(): void
}

class StdioServerTransport {
    -process: Process
    -writer: BufferedWriter
    -reader: BufferedReader
    +StdioServerTransport(ServerParameters)
}

class ServerParameters {
    -command: String[]
    -workingDirectory: File
    -environment: Map<String, String>
}

class ServerParametersParser {
    +{static} parse(String): ServerParameters
}

class Assert {
    +{static} notNull(Object, String): void
    +{static} hasText(String, String): void
}

' Relationships
McpAsyncTransport <|.. DefaultMcpTransport
DefaultMcpTransport <|-- StdioServerTransport

McpClient <|.. McpSyncClient
McpAsyncSession <|.. McpAsyncClient

McpSyncClient o-- McpAsyncClient
McpAsyncClient o-- McpAsyncTransport
McpAsyncClient o-- McpAsyncSession

StdioServerTransport o-- ServerParameters
ServerParameters <.. ServerParametersParser : creates

' Package organization
package "spring.ai.mcp.spec" {
    ' McpAsyncTransport
    ' McpAsyncSession
    ' DefaultMcpTransport
}

package "spring.ai.mcp.client" {
    ' McpClient
    ' McpAsyncClient
    ' McpSyncClient
    
    package "stdio" {
        ' StdioServerTransport
        ' ServerParameters
        ' ServerParametersParser
    }
    
    package "util" {
        ' Assert
    }
}

@enduml