@Override
    public Credentials getCredentials() {
        return credentials;
    }
Creates a new AuthenticationFailureEvent which represents a failure
to authenticate the given credentials.

@param credentials
    The credentials which failed authentication.

@param authProvider
    The AuthenticationProvider that caused the failure, or null if there
    is no such AuthenticationProvider.

@param failure
    The Throwable that was thrown resulting in the failure, or null if
    there is no such Throwable.
guacamole-ext/src/main/java/org/apache/guacamole/net/event/AuthenticationFailureEvent.java