• NAME
• SYNOPSIS
• DESCRIPTION
• Methods
• new($str_or_ref, %options)
• get_actuate
• set_actuate($actuate)
• get_encoding
• set_encoding($encoding)
• get_expires
• set_expires($expires)
• get_href
• set_href($href)
• get_rights
• set_rights($rights)
• get_type
• set_type($type)
• Notes on class internals
• WARNINGS
• SEE ALSO
• AUTHOR
• VERSION

NAME

VOTABLE::STREAM - VOTABLE STREAM XML element class

SYNOPSIS

use VOTABLE::STREAM;

DESCRIPTION

This class implements the STREAM element from the VOTABLE DTD. This element is used to encapsulate streams of arbitrary data, possible encoded and/or compressed.

The STREAM element is a Tier 0 element, and is described by the following excerpt from the VOTABLE 1.0 DTD:

 <!ELEMENT STREAM (#PCDATA)>
 <!ATTLIST STREAM
         type (locator | other) "locator"
         href CDATA #IMPLIED
         actuate (onLoad | onRequest | other | none) "onRequest"
         encoding (gzip | base64 | dynamic | none) "none"
         expires CDATA #IMPLIED
         rights CDATA #IMPLIED
 >

Methods

new($str_or_ref, %options)

Create a new VOTABLE::STREAM object, and return a reference to it. If the first argument ($str_or_ref) is a string, it is used as the initial PCDATA content of the STREAM element. If the first argument is a reference to a XML::DOM::Element object, that object is used to initialize the new STREAM element (implicitly assuming that the XML::DOM::Element object contains a valid STREAM element). The %options hash is used to set the attributes of the new element. If the first argument is missing or undefined, or an empty string, create and return an empty VOTABLE::STREAM object. Return undef if an error occurs.

get_actuate

Return the value of the actuate attribute. Return undef if the attribute has not been set, or an error occurs.

set_actuate($actuate)

Set the value of the actuate attribute to the specified value. Return the new value of the attribute on success, or undef if an error occurs.

get_encoding

Return the value of the encoding attribute. Return undef if the attribute has not been set, or an error occurs.

set_encoding($encoding)

Set the value of the encoding attribute to the specified value. Return the new value of the attribute on success, or undef if an error occurs.

get_expires

Return the value of the expires attribute. Return undef if the attribute has not been set, or an error occurs.

set_expires($expires)

Set the value of the expires attribute to the specified value. Return the new value of the attribute on success, or undef if an error occurs.

get_href

Return the value of the href attribute. Return undef if the attribute has not been set, or an error occurs.

set_href($href)

Set the value of the href attribute to the specified value. Return the new value of the attribute on success, or undef if an error occurs.

get_rights

Return the value of the rights attribute. Return undef if the attribute has not been set, or an error occurs.

set_rights($rights)

Set the value of the rights attribute to the specified value. Return the new value of the attribute on success, or undef if an error occurs.

get_type

Return the value of the type attribute. Return undef if the attribute has not been set, or an error occurs.

set_type($type)

Set the value of the type attribute to the specified value. Return the new value of the attribute on success, or undef if an error occurs.

Notes on class internals

• Method names that begin with a leading underscore ('_') are for internal use only, and should not be used outside of the VOTABLE class hierarchy.

• The names of the get_XXX and set_XXX accessors for attributes and elements are derived directly from the names of the attributes or elements. Attribute and element names containing embedded hyphens ('-') use accessors where the hyphen is mapped to an underscore ('_') in the name of the accessor method. This is a necessity, since the hyphen is not a valid name character in Perl.

WARNINGS

• This code (perhaps unwisely) assumes that object internal structure is always maintained. For example, this code assumes that every VOTABLE::STREAM object always has an underlying XML::DOM::Element object. As long as the internal structure is manipulated only by the publicly-available methods, this should be an adequate assumption. If a method detects an aberrant case, a warning message is printed (using the Carp::carp subroutine), and the method fails.

• Similarly, this code assumes that XML::DOM methods always succeed. If a method detects an aberrant case, a warning message is printed (using the Carp::carp subroutine), and the method fails.

• Most attribute set_XXX accessors do not perform validation of the new attribute values. The exceptions are the accessors for attributes with enumerated values; the new value is checked against the list of acceptable values, as defined in the DTD.

SEE ALSO

VOTABLE, VOTABLE::BINARY, VOTABLE::FITS

AUTHOR

Eric Winter, NASA GSFC (elwinter@milkyway.gsfc.nasa.gov)

VERSION

$Id: STREAM.pm,v 1.1.1.7 2002/05/21 14:13:06 elwinter Exp $