Koha/marc/File.pm

201 lines
3.3 KiB
Perl

package MARC::File;
# Copyright 2000-2002 Katipo Communications
#
# This file is part of Koha.
#
# Koha is free software; you can redistribute it and/or modify it under the
# terms of the GNU General Public License as published by the Free Software
# Foundation; either version 2 of the License, or (at your option) any later
# version.
#
# Koha is distributed in the hope that it will be useful, but WITHOUT ANY
# WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
# A PARTICULAR PURPOSE. See the GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License along with
# Koha; if not, write to the Free Software Foundation, Inc., 59 Temple Place,
# Suite 330, Boston, MA 02111-1307 USA
=head1 NAME
MARC::File - Base class for files of MARC records
=cut
use 5.6.0;
use strict;
use integer;
use vars qw( $VERSION $ERROR );
=head1 VERSION
Version 0.93
$Id$
=cut
our $VERSION = '0.93';
=head1 SYNOPSIS
use MARC::File::USMARC;
my $file = MARC::File::USMARC->in( $filename );
while ( my $marc = $file->next() ) {
# Do something
}
$file->close();
undef $file;
=head1 EXPORT
None.
=head1 METHODS
=head2 in()
Opens a file for input.
=cut
sub in {
my $class = shift;
my $filename = shift;
my $self = {
filename => $filename,
};
bless $self, $class;
if ( !open( $self->{fh}, "<", $filename ) ) {
undef $self;
$MARC::File::ERROR = "Couldn't open $filename: $!";
}
return $self;
} # new()
sub indata {
my $class = shift;
my $data = shift;
my $self = {
fh => '',
data => $data,
pointer => 0,
};
bless $self, $class;
# if ( !open( $self->{fh}, "<", $filename ) ) {
# undef $self;
# $MARC::File::ERROR = "Couldn't open $filename: $!";
# }
return $self;
} # new()
sub out {
die "Not yet written";
}
=head2 next()
Reads the next record from the file handle passed in.
=cut
sub next {
my $self = shift;
my $rec = $self->_next();
return $rec ? $self->decode($rec) : undef;
}
=head2 skip
Skips over the next record in the file. Same as C<next()>,
without the overhead of parsing a record you're going to throw away
anyway.
Returns 1 or undef.
=cut
sub skip {
my $self = shift;
my $rec = $self->_next();
return $rec ? 1 : undef;
}
sub close {
my $self = shift;
close( $self->{fh} );
delete $self->{fh};
return;
}
sub _unimplemented() {
my $self = shift;
my $method = shift;
warn "Method $method must be overridden";
}
sub write { $_[0]->_unimplemented("write"); }
sub decode { $_[0]->_unimplemented("decode"); }
# NOTE: _gripe can be called as an object method, or not. Your choice.
sub _gripe(@) {
if ( @_ ) {
shift if ref($_[0]) =~ /^MARC::File/; # Skip first parm if it's a $self
$ERROR = join( "", @_ );
}
return undef;
}
1;
__END__
=head1 RELATED MODULES
L<MARC::Record>
=head1 TODO
=over 4
=item * C<out()> method
We only handle files for input right now.
=back
=cut
=head1 LICENSE
This code may be distributed under the same terms as Perl itself.
Please note that these modules are not products of or supported by the
employers of the various contributors to the code.
=head1 AUTHOR
Andy Lester, E<lt>marc@petdance.comE<gt> or E<lt>alester@flr.follett.comE<gt>
=cut