Authenticator (Dropwizard Project 2.0.18 API)

Type Parameters:

C - the type of credentials the authenticator can authenticate

P - the type of principals the authenticator returns

All Known Implementing Classes:

CachingAuthenticator, ExampleAuthenticator
```
public interface Authenticator<C,P extends Principal>
```
An interface for classes which authenticate user-provided credentials and return principal objects.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`Optional<P>`	`authenticate(C credentials)`	Given a set of user-provided credentials, return an optional principal.

- Method Detail
  - authenticate
```
Optional<P> authenticate(C credentials)
                  throws AuthenticationException
```
    Given a set of user-provided credentials, return an optional principal. If the credentials are valid and map to a principal, returns an Optional.of(Object). If the credentials are invalid, returns an Optional.empty().
    
    Parameters:
    
    credentials - a set of user-provided credentials
    
    Returns:
    
    either an authenticated principal or an absent optional
    
    Throws:
    
    AuthenticationException - if the credentials cannot be authenticated due to an underlying error