| class  | InvalidGrantException | Represents an exception while processing OAuth 2.0 request and response. | 
| class  | OAuth20AccessDeniedException | Represents an authorization exception to access protected resources. | 
| class  | OAuth20AuthorizationCodeInvalidClientException | Represents an illegal authorization code exception presented by a client. | 
| class  | OAuth20BadParameterFormatException | Represents a bad parameter format exception presented in OAuth request. | 
| class  | OAuth20DuplicateParameterException | Represents a duplicated parameter exception in OAuth request. | 
| class  | OAuth20Exception | Represents an exception while processing OAuth 2.0 request and response. | 
| class  | OAuth20InternalException | Represents an OAuth service provider internal exception while processing OAuth request. | 
| class  | OAuth20InvalidClientException | Represents an invalid client exception in an OAuth request. | 
| class  | OAuth20InvalidClientSecretException | Represents an invalid client secret exception in an OAuth request. | 
| class  | OAuth20InvalidGrantTypeException | Represents an invalid or not supported grant type in an OAuth request. | 
| class  | OAuth20InvalidRedirectUriException | Represents an invalid redirect URI exception in an OAuth request. | 
| class  | OAuth20InvalidResponseTypeException | Represents an invalid response type exception in an OAuth request. | 
| class  | OAuth20InvalidScopeException | Represents an invalid request scope exception in an OAuth request. | 
| class  | OAuth20InvalidTokenException | Represents an invalid token exception in an OAuth request. | 
| class  | OAuth20InvalidTokenRequestMethodException | Represents an invalid token request method exception in an OAuth request. | 
| class  | OAuth20MediatorException | Represents a mediation exception in an OAuth request. | 
| class  | OAuth20MismatchedClientAuthenticationException | Represents a mismatch exception that the client ID does not match the authenticated client. | 
| class  | OAuth20MismatchedRedirectUriException | Represents an error that occurs when the redirect URI passed in the request
 to the token endpoint does not match the redirect URI associated with the grant. | 
| class  | OAuth20MissingParameterException | Represents a missing request parameter exception. | 
| class  | OAuth20PublicClientCredentialsException | Represents an access denied exception for public client when trying to use
 the client_credentials grant type. | 
| class  | OAuth20PublicClientForbiddenException | Represents an access denied exception for public client. | 
| class  | OAuth20RefreshTokenInvalidClientException | Represents a refresh token exception due to mismatched client. |