Interface UserCache
- All Known Implementing Classes:
NullUserCache
,SpringCacheBasedUserCache
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.
-
Method Summary
Modifier and TypeMethodDescriptiongetUserFromCache
(String username) Obtains aUserDetails
from the cache.void
putUserInCache
(UserDetails user) Places aUserDetails
in the cache.void
removeUserFromCache
(String username) Removes the specified user from the cache.
-
Method Details
-
getUserFromCache
Obtains aUserDetails
from the cache.- Parameters:
username
- theUser.getUsername()
used to place the user in the cache- Returns:
- the populated
UserDetails
ornull
if the user could not be found or if the cache entry has expired
-
putUserInCache
Places aUserDetails
in the cache. Theusername
is the key used to subsequently retrieve theUserDetails
.- Parameters:
user
- the fully populatedUserDetails
to place in the cache
-
removeUserFromCache
Removes the specified user from the cache. Theusername
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
-