Represents a parsed Last-Modified HTTP response header.
The last modified date for the requested object (in "HTTP-date" format as defined by RFC 7231).
Example
Last-Modified: Tue, 15 Nov 1994 12:45:26 GMT
RFC2616 Specification
The Last-Modified entity-header field indicates the date and time at which the origin server believes the variant was
last modified.
Last-Modified = "Last-Modified" ":" HTTP-date
An example of its use is...
Last-Modified: Tue, 15 Nov 1994 12:45:26 GMT
The exact meaning of this header field depends on the implementation of the origin server and the nature of the
original resource.
For files, it may be just the file system last-modified time.
For entities with dynamically included parts, it may be the most recent of the set of last-modify times for its
component parts.
For database gateways, it may be the last-update time stamp of the record.
For virtual objects, it may be the last time the internal state changed.
An origin server MUST NOT send a Last-Modified date which is later than the server's time of message origination.
In such cases, where the resource's last modification would indicate some time in the future, the server MUST replace
that date with the message origination date.
An origin server SHOULD obtain the Last-Modified value of the entity as close as possible to the time that it
generates the Date value of its response.
This allows a recipient to make an accurate assessment of the entity's modification time, especially if the entity
changes near the time that the response is generated.
HTTP/1.1 servers SHOULD send Last-Modified whenever feasible.
See Also: