# Package org.apache.coyote.http11.upgrade.servlet31

Interface Summary
Interface | Description
--- | ---
HttpUpgradeHandler | Interface between the HTTP upgrade process and the new protocol.
ReadListener | Receives notification of read events when using non-blocking IO.
WebConnection | The interface used by a `HttpUpgradeHandler` to interact with an upgraded HTTP connection.
WriteListener | Receives notification of write events when using non-blocking IO.