Update the contents.
Zlib compression level
Get uncompressed data. The call may be expensive, result is cached (in uncompressedData).
Return last modified time. Used for Last-Modified and If-Modified-Since headers. Called when cached data is invalidated; return value is cached. Returns current (invalidation) time by default.
Caching policy. To be set during subclass construction.
MIME content type. To be set during subclass construction.
Called every time a request is done. Can be used to check if cached data expired, and invalidate() it. By default is a no-op.
Clear cached uncompressed and compressed data. An alternative to calling invalidate() from a subclass is to simply create a new class instance when data becomes stale (overhead is negligible).
Used by application code.
A generic cached resource, for resources that change less often than they are requested (e.g. RSS feeds).