A cache session can only give out one descriptor with WRITE access
to a given cache entry at a time. Until the client calls MarkValid on
its descriptor, other attempts to open the same cache entry will block.
Synchronous cache access. This method fails if it is called on the main
thread. Use asyncOpenCacheEntry() instead. This returns a unique
descriptor each time it is called, even if the same key is specified.
When called by multiple threads for write access, only one writable
descriptor will be granted. If ‘blockingMode’ is set to false, it will
return NS_ERROR_CACHE_WAIT_FOR_VALIDATION rather than block when another
descriptor has been given WRITE access but hasn’t validated the entry yet.
Asynchronous cache access. Does not block the calling thread. Instead,
the listener will be notified when the descriptor is available. If
‘noWait’ is set to true, the listener will be notified immediately with
status NS_ERROR_CACHE_WAIT_FOR_VALIDATION rather than queuing the request
when another descriptor has been given WRITE access but hasn’t validated
the entry yet.
Evict all entries for this session’s clientID according to its storagePolicy.
Return whether any of the cache devices implied by the session storage policy
are currently enabled for instantiation if they don’t already exist.
Asynchronously doom an entry specified by the key. Listener will be
notified about the status of the operation. Null may be passed if caller
doesn’t care about the result.
Expired entries will be doomed or evicted if this attribute is set to
true. If false, expired entries will be returned (useful for offline-
mode and clients, such as HTTP, that can update the valid lifetime of
cached content). This attribute defaults to true.
When set, entries created with this session will be placed to a cache
based at this directory. Use when storing entries to a different
profile than the active profile of the the current running application
process.
Private entries will be doomed when the last private browsing session
finishes.