| Interface Summary | 
| AccessLog | Intended for use by a Valveto indicate that theValveprovides access logging. | 
| Authenticator | An Authenticator is a component (usually a Valve or Container) that
 provides some sort of authentication service. | 
| Cluster | A Cluster works as a Cluster client/server for the local host
 Different Cluster implementations can be used to support different
 ways to communicate within the Cluster. | 
| CometEvent | The CometEvent interface. | 
| CometFilter | A Comet filter, similar to regular filters, performs filtering tasks on either 
 the request to a resource (a Comet servlet), or on the response from a resource, or both. | 
| CometFilterChain | A CometFilterChain is an object provided by the servlet container to the developer
 giving a view into the invocation chain of a filtered event for a resource. | 
| CometProcessor | This interface should be implemented by servlets which would like to handle
 asynchronous IO, recieving events when data is available for reading, and
 being able to output data without the need for being invoked by the container. | 
| Contained | Decoupling interface which specifies that an implementing class is
 associated with at most one Container instance. | 
| Container | A Container is an object that can execute requests received from
 a client, and return responses based on those requests. | 
| ContainerListener | Interface defining a listener for significant Container generated events. | 
| ContainerServlet | A ContainerServlet is a servlet that has access to Catalina
 internal functionality, and is loaded from the Catalina class loader
 instead of the web application class loader. | 
| Context | A Context is a Container that represents a servlet context, and
 therefore an individual web application, in the Catalina servlet engine. | 
| Engine | An Engine is a Container that represents the entire Catalina servlet
 engine. | 
| Executor |  | 
| Group | Abstract representation of a group of Users in aUserDatabase. | 
| Host | A Host is a Container that represents a virtual host in the
 Catalina servlet engine. | 
| InstanceListener | Interface defining a listener for significant events related to a
 specific servlet instance, rather than to the Wrapper component that
 is managing that instance. | 
| Lifecycle | Common interface for component life cycle methods. | 
| LifecycleListener | Interface defining a listener for significant events (including "component
 start" and "component stop" generated by a component that implements the
 Lifecycle interface. | 
| Loader | A Loader represents a Java ClassLoader implementation that can
 be used by a Container to load class files (within a repository associated
 with the Loader) that are designed to be reloaded upon request, as well as
 a mechanism to detect whether changes have occurred in the underlying
 repository. | 
| Manager | A Manager manages the pool of Sessions that are associated with a
 particular Container. | 
| Pipeline | Interface describing a collection of Valves that should be executed
 in sequence when the invoke()method is invoked. | 
| Realm | A Realm is a read-only facade for an underlying security realm
 used to authenticate individual users, and identify the security roles
 associated with those users. | 
| Role | Abstract representation of a security role, suitable for use in
 environments like JAAS that want to deal with Principals. | 
| Server | A Serverelement represents the entire Catalina
 servlet container. | 
| Service | A Service is a group of one or more
 Connectors that share a single Container
 to process their incoming requests. | 
| Session | A Session is the Catalina-internal facade for an HttpSessionthat is used to maintain state information
 between requests for a particular user of a web application. | 
| SessionListener | Interface defining a listener for significant Session generated events. | 
| Store | A Store is the abstraction of a Catalina component that provides
 persistent storage and loading of Sessions and their associated user data. | 
| User | Abstract representation of a user in a UserDatabase. | 
| UserDatabase | Abstract representation of a database of Users andGroups that can be maintained by an application,
 along with definitions of correspondingRoles, and
 referenced by aRealmfor authentication and access control. | 
| Valve | A Valve is a request processing component associated with a
 particular Container. | 
| Wrapper | A Wrapper is a Container that represents an individual servlet
 definition from the deployment descriptor of the web application. |