# Package org.apache.catalina.authenticator

This package contains `Authenticator` implementations for the various supported authentication methods (BASIC, DIGEST, and FORM).

See: Description

Class Summary
Class | Description
--- | ---
AuthenticatorBase | Basic implementation of the Valve interface that enforces the `<security-constraint>` elements in the web application deployment descriptor.
BasicAuthenticator | An Authenticator and Valve implementation of HTTP BASIC Authentication, as outlined in RFC 2617: "HTTP Authentication: Basic and Digest Access Authentication."
Constants |
DigestAuthenticator | An Authenticator and Valve implementation of HTTP DIGEST Authentication (see RFC 2069).
FormAuthenticator | An Authenticator and Valve implementation of FORM BASED Authentication, as described in the Servlet API Specification, Version 2.2.
NonLoginAuthenticator | An Authenticator and Valve implementation that checks only security constraints not involving user authentication.
SavedRequest | Object that saves the critical information from a request so that form-based authentication can reproduce it once the user has been authenticated.
SingleSignOn | A Valve that supports a "single sign on" user experience, where the security identity of a user who successfully authenticates to one web application is propagated to other web applications in the same security domain.
SingleSignOnEntry | A class that represents entries in the cache of authenticated users.
SpnegoAuthenticator | A SPNEGO authenticator that uses the SPNEGO/Kerberos support built in to Java 6.
SSLAuthenticator | An Authenticator and Valve implementation of authentication that utilizes SSL certificates to identify client users.

## Package org.apache.catalina.authenticator Description

This package contains `Authenticator` implementations for the various supported authentication methods (BASIC, DIGEST, and FORM). In addition, there is a convenience base class, `AuthenticatorBase`, for customized `Authenticator` implementations.

If you are using the standard context configuration class (`org.apache.catalina.startup.ContextConfig`) to configure the Authenticator associated with a particular context, you can register the Java class to be used for each possible authentication method by modifying the following Properties file:

        src/share/org/apache/catalina/startup/Authenticators.properties

Each of the standard implementations extends a common base class (`AuthenticatorBase`), which is configured by setting the following JavaBeans properties (with default values in square brackets):

- cache - Should we cache authenticated Principals (thus avoiding per-request lookups in our underyling `Realm`) if this request is part of an HTTP session? [true]
- debug - Debugging detail level for this component. [0]

The standard authentication methods that are currently provided include:

- BasicAuthenticator - Implements HTTP BASIC authentication, as described in RFC 2617.
- DigestAuthenticator - Implements HTTP DIGEST authentication, as described in RFC 2617.
- FormAuthenticator - Implements FORM-BASED authentication, as described in the Servlet API Specification, version 2.2.