| Interface | Description | 
|---|---|
| MetadataExtractor | Strategy to extract a map of value(s) from  Payloadmetadata, which
 could be composite metadata with multiple entries. | 
| MetadataExtractorRegistry | Stores registrations of extractors for metadata entries. | 
| RSocketConnectorConfigurer | Strategy to apply configuration to an  RSocketConnector. | 
| RSocketRequester | A thin wrapper around a sending  RSocketwith a fluent API accepting
 and returning higher level Objects for input and for output, along with
 methods to prepare routing and other metadata. | 
| RSocketRequester.Builder | Builder to create a requester by connecting to a server. | 
| RSocketRequester.MetadataSpec<S extends RSocketRequester.MetadataSpec<S>> | Spec for providing additional composite metadata entries. | 
| RSocketRequester.RequestSpec | Spec to declare the input for an RSocket request. | 
| RSocketRequester.RetrieveSpec | Spec to declare the expected output for an RSocket request. | 
| RSocketStrategies | Access to strategies for use by RSocket requester and responder components. | 
| RSocketStrategies.Builder | The builder options for creating  RSocketStrategies. | 
| Class | Description | 
|---|---|
| DefaultMetadataExtractor | Default  MetadataExtractorimplementation that relies onDecoders to deserialize the content of metadata entries. | 
| PayloadUtils | Static utility methods to create  PayloadfromDataBuffers
 and vice versa. |