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HTTPResource

The basic class of all resources accessible through the HTTP protocol. As a webadmin, you shouldn't try to install an instance of an HTTPResource, since it doesn't provide any implementation of the actual HTTP methods.


Inherits

The HTTPResource class inherits from the following classes:


Attributes description

The HTTPResource defines the following attributes:


parent

semantics
The parent of a resource is the resource that is responsible for its loading in memory. All resources should have a parent, except for the server's root resource (whose parent is null)
type
This attribute is a computed ObjectAttribute
default value
This attribute defaults to the resource that loaded it into memory, as explained above.


url
semantics
The location of this resource within the server that exports it. This is given as a string, parseable into a Java URL.
type
This attribute is a computed StringAttribute
default value
This attribute defaults to the concatenation of the resource's parent url attribute with its own name (or identifier).


server
semantics
The server that makes this resource accessible through HTTP.
type
This attribute is a computed ObjectAttribute
default value
This attribute defaults to its parent's server attribute value.


quality
semantics
A rating of the quality of this resource's content. The rating is provided as a number between 0.0 and 1.0. It is used mainly by the NegotiatedResource to negotiate among its set of variants.
type
This attribute is an editable DoubleAttribute.
default value
This attribute defaults to 1.0.


title
semantics
The title of this resource. This attribute can be either computed from the resource content (e.g. if the content is an HTML file which has some META tag), or provided for informational purposes (even if the resource's content type is not text/html.)
type
This attribute is a computed and/or editable StringAttribute.
default value
This attribute is undefined by default.


content-language
semantics
The natural language of the resource content. This is used mainly by the NegotiatedResource to negotiate among its set of variant resources. The value of this attribute can be either extracted from the resource content (e.g. if it is an HTML file that includes some appropriate META tag), or provided for informational purposes.
type
This attribute is a computed and/or editable LanguageAttribute.
default value
This attribute is undefined by default.


content-encoding
semantics
The encoding in which the resource's contenht is stored. Right now this can only be a single token (as described in the HTTP/1.0 specification).
type
This attribute is a computed and/or editable EncodingAttribute.
default value
This attribute is undefined by default.


content-type
semantics
The (MIME) type of the resource's content.
type
This attribute is a computed and/or editable MimeTypeAttribute.
default value
This attribute is undefined by default.


content-length
semantics
The length of the resource's content.
type
This attribute is a computed IntegerAttribute.
default value
This attribute is undefined by default. It is up to sub-classes of resources to either generate it dynamically, or cache it from its sources (e.g.the FileResource caches this information that it gets through file system calls).


last-modified
semantics
The date of the last modification of this resource.
type
This attribute is a computed  and/or editable DateAttribute.
default value
This attribute is undefined by default, it is up to sub-classes of resources to either generate it dynamically, or cache it from its sources (as above).


expires
semantics
The date at which this resource expires.
type
This attribute is a computed  and/or editable DateAttribute.
default value
This attribute is undefined by default, it is up to sub-classes of resources to either generate it dynamically, or cache it from its sources (as above).


icon
semantics
Any icon to be associated with the resource. This is used, for example, to produce nice directory listings.
type
This attribute is an editable StringAttribute
default value
This attribute is undefined by default.


maxage
semantics
This attribute defines the allowed drift between the real content of a resource, and the one that is sent as request replies. The bigger this value, the more efficient the server can be, since it will be able to reuse cachd request replies for a longer time. This attribute takes effect only if it is defined, and if the resource provides a meaningfull last-modified attribute value.
type
This attribute is an editable IntegerAttribute
default value
This attribute is undefined by default.


Jigsaw Team
$Id: w3c.jigsaw.resources.HTTPResource.html,v 1.1 1996/04/11 20:05:11 abaird Exp $