libxml-sax-perl/lib/XML/SAX/DocumentLocator.pm

135 lines
2.8 KiB
Perl

# $Id$
package XML::SAX::DocumentLocator;
use strict;
sub new {
my $class = shift;
my %object;
tie %object, $class, @_;
return bless \%object, $class;
}
sub TIEHASH {
my $class = shift;
my ($pubmeth, $sysmeth, $linemeth, $colmeth, $encmeth, $xmlvmeth) = @_;
return bless {
pubmeth => $pubmeth,
sysmeth => $sysmeth,
linemeth => $linemeth,
colmeth => $colmeth,
encmeth => $encmeth,
xmlvmeth => $xmlvmeth,
}, $class;
}
sub FETCH {
my ($self, $key) = @_;
my $method;
if ($key eq 'PublicId') {
$method = $self->{pubmeth};
}
elsif ($key eq 'SystemId') {
$method = $self->{sysmeth};
}
elsif ($key eq 'LineNumber') {
$method = $self->{linemeth};
}
elsif ($key eq 'ColumnNumber') {
$method = $self->{colmeth};
}
elsif ($key eq 'Encoding') {
$method = $self->{encmeth};
}
elsif ($key eq 'XMLVersion') {
$method = $self->{xmlvmeth};
}
if ($method) {
my $value = $method->($key);
return $value;
}
return undef;
}
sub EXISTS {
my ($self, $key) = @_;
if ($key =~ /^(PublicId|SystemId|LineNumber|ColumnNumber|Encoding|XMLVersion)$/) {
return 1;
}
return 0;
}
sub STORE {
my ($self, $key, $value) = @_;
}
sub DELETE {
my ($self, $key) = @_;
}
sub CLEAR {
my ($self) = @_;
}
sub FIRSTKEY {
my ($self) = @_;
# assignment resets.
$self->{keys} = {
PublicId => 1,
SystemId => 1,
LineNumber => 1,
ColumnNumber => 1,
Encoding => 1,
XMLVersion => 1,
};
return each %{$self->{keys}};
}
sub NEXTKEY {
my ($self, $lastkey) = @_;
return each %{$self->{keys}};
}
1;
__END__
=head1 NAME
XML::SAX::DocumentLocator - Helper class for document locators
=head1 SYNOPSIS
my $locator = XML::SAX::DocumentLocator->new(
sub { $object->get_public_id },
sub { $object->get_system_id },
sub { $reader->current_line },
sub { $reader->current_column },
sub { $reader->get_encoding },
sub { $reader->get_xml_version },
);
=head1 DESCRIPTION
This module gives you a tied hash reference that calls the
specified closures when asked for PublicId, SystemId,
LineNumber and ColumnNumber.
It is useful for writing SAX Parsers so that you don't have
to constantly update the line numbers in a hash reference on
the object you pass to set_document_locator(). See the source
code for XML::SAX::PurePerl for a usage example.
=head1 API
There is only 1 method: C<new>. Simply pass it a list of
closures that when called will return the PublicId, the
SystemId, the LineNumber, the ColumnNumber, the Encoding
and the XMLVersion respectively.
The closures are passed a single parameter, the key being
requested. But you're free to ignore that.
=cut