org.springframework.security.core.userdetails

Interface UserCache

All Known Implementing Classes:

EhCacheBasedUserCache, NullUserCache, SpringCacheBasedUserCache

public interface UserCache

Provides a cache of UserDetails objects.

Implementations should provide appropriate methods to set their cache parameters (e.g. time-to-live) and/or force removal of entities before their normal expiration. These are not part of the UserCache interface contract because they vary depending on the type of caching system used (in-memory, disk, cluster, hybrid etc.).

Caching is generally only required in applications which do not maintain server-side state, such as remote clients or web services. The authentication credentials are then presented on each invocation and the overhead of accessing a database or other persistent storage mechanism to validate would be excessive. In this case, you would configure a cache to store the UserDetails information rather than loading it each time.

Author:

Ben Alex

See Also:

AbstractUserDetailsAuthenticationProvider

Method Summary

Modifier and Type	Method and Description
UserDetails	getUserFromCache(String username) Obtains a UserDetails from the cache.
void	putUserInCache(UserDetails user) Places a UserDetails in the cache.
void	removeUserFromCache(String username) Removes the specified user from the cache.

Method Detail

getUserFromCache

UserDetails getUserFromCache(String username)

Obtains a UserDetails from the cache.

Parameters:

username - the User.getUsername() used to place the user in the cache

Returns:

the populated UserDetails or null if the user could not be found or if the cache entry has expired

putUserInCache

void putUserInCache(UserDetails user)

Places a UserDetails in the cache. The username is the key used to subsequently retrieve the UserDetails.

Parameters:

user - the fully populated UserDetails to place in the cache

removeUserFromCache

void removeUserFromCache(String username)

Removes the specified user from the cache. The username is the key used to remove the user. If the user is not found, the method should simply return (not thrown an exception).

Some cache implementations may not support eviction from the cache, in which case they should provide appropriate behaviour to alter the user in either its documentation, via an exception, or through a log message.

Parameters:

username - to be evicted from the cache