Calling this method instructs the cache to return null to all get(K) calls and ignore any
put(K, T) calls from the current thread until the cache is cleared.
Calling this method instructs the cache to return null to all get(K) calls and ignore any
put(K, T) calls from the current thread until the cache is cleared. Context: after a write operation on
a connection (which is assumed to be handled exclusively by a dedicated thread), the local cache must be cleared
and the global cache bypassed until the connection is returned.