ProtocolInfo (Apache Hadoop Common 3.4.1.200-dep-1000 API)

```
@Retention(RUNTIME)
public @interface ProtocolInfo
```
The protocol name that is used when a client and server connect. By default the class name of the protocol interface is the protocol name. Why override the default name (i.e. the class name)? One use case overriding the default name (i.e. the class name) is when there are multiple implementations of the same protocol, each with say a different version/serialization. In Hadoop this is used to allow multiple server and client adapters for different versions of the same protocol service.

Required Elements
Modifier and Type	Required Element	Description
`java.lang.String`	`protocolName`

Optional Elements
Modifier and Type	Optional Element	Description
`long`	`protocolVersion`

Annotation Type ProtocolInfo