# # Copyright (C) 1998, 1999 Ken MacLeod # XML::Grove::PerlSAX is free software; you can redistribute it and/or # modify it under the same terms as Perl itself. # # $Id: PerlSAX.pm,v 1.3 1999/08/17 15:01:28 kmacleod Exp $ # use strict; package XML::Grove::PerlSAX; use UNIVERSAL; use Data::Grove::Visitor; sub new { my $type = shift; my $self = ($#_ == 0) ? shift : { @_ }; return bless $self, $type; } sub parse { my $self = shift; die "XML::Grove::PerlSAX: parser instance ($self) already parsing\n" if (defined $self->{ParseOptions}); # If there's one arg and it's a subclass of Data::Grove, # then that's what we're parsing my $args; if (scalar (@_) == 1 && UNIVERSAL::isa($_[0], 'Data::Grove')) { $args = { Source => { Grove => shift } }; } else { $args = (scalar (@_) == 1) ? shift : { @_ }; } my $parse_options = { %$self, %$args }; $self->{ParseOptions} = $parse_options; # ensure that we have at least one source if (!defined $parse_options->{Source} || !(defined $parse_options->{Source}{Grove})) { die "XML::Grove::PerlSAX: no source defined for parse\n"; } # assign default Handler to any undefined handlers if (defined $parse_options->{Handler}) { $parse_options->{DocumentHandler} = $parse_options->{Handler} if (!defined $parse_options->{DocumentHandler}); } # ensure that we have a DocumentHandler if (!defined $parse_options->{DocumentHandler}) { die "XML::Grove::PerlSAX: no Handler or DocumentHandler defined for parse\n"; } # cache DocumentHandler in self for callbacks $self->{DocumentHandler} = $parse_options->{DocumentHandler}; if (ref($self->{Source}{Grove}) !~ /Document/) { $self->{DocumentHandler}->start_document( { } ); $parse_options->{Source}{Grove}->accept($self); return $self->{DocumentHandler}->end_document( { } ); } else { $self->{Source}{Grove}->accept($self); } # clean up parser instance delete $self->{ParseOptions}; delete $self->{DocumentHandler}; } sub _parse_self { my $grove = shift; my $self = ($#_ == 0) ? shift : { @_ }; bless $self, 'XML::Grove::PerlSAX'; if (ref($grove) !~ /Document/) { $self->{DocumentHandler}->start_document( { } ); $grove->accept($self); return $self->{DocumentHandler}->end_document( { } ); } else { return $grove->accept($self); } } sub visit_document { my $self = shift; my $grove = shift; $self->{DocumentHandler}->start_document($grove); $grove->children_accept($self); return $self->{DocumentHandler}->end_document($grove); } sub visit_element { my $self = shift; my $element = shift; $self->{DocumentHandler}->start_element($element); $element->children_accept($self); return $self->{DocumentHandler}->end_element($element); } sub visit_entity { my $self = shift; my $entity = shift; return $self->{DocumentHandler}->int_entity($entity); } sub visit_pi { my $self = shift; my $pi = shift; return $self->{DocumentHandler}->processing_instruction($pi); } sub visit_comment { my $self = shift; my $comment = shift; return $self->{DocumentHandler}->comment($comment); } sub visit_characters { my $self = shift; my $characters = shift; return $self->{DocumentHandler}->characters($characters); } package XML::Grove::Document; sub parse { goto &XML::Grove::PerlSAX::_parse_self; } package XML::Grove::Element; sub parse { goto &XML::Grove::PerlSAX::_parse_self; } 1; __END__ =head1 NAME XML::Grove::PerlSAX - an PerlSAX event interface for XML objects =head1 SYNOPSIS use XML::Grove::PerlSAX; $parser = XML::Grove::PerlSAX->new( [OPTIONS] ); $result = $parser->parse( [OPTIONS] ); # or $result = $xml_object->parse( [OPTIONS] ); =head1 DESCRIPTION C is a PerlSAX parser that generates PerlSAX events from XML::Grove objects. This man page summarizes the specific options, handlers, and properties supported by C; please refer to the PerlSAX standard in `C' for general usage information. =head1 METHODS =over 4 =item new Creates a new parser object. Default options for parsing, described below, are passed as key-value pairs or as a single hash. Options may be changed directly in the parser object unless stated otherwise. Options passed to `C' override the default options in the parser object for the duration of the parse. =item parse Parses a document. Options, described below, are passed as key-value pairs or as a single hash. Options passed to `C' override default options in the parser object. =back =head1 OPTIONS The following options are supported by C: Handler default handler to receive events DocumentHandler handler to receive document events Source hash containing the input source for parsing If no handlers are provided then all events will be silently ignored. If a single grove argument is passed to the `C' method, it is treated as if a `C' option was given with a `C' parameter. The `C' hash may contain the following parameters: Grove The grove object used to generate parse events.. =head1 HANDLERS The following events are generated by C. XML::Grove::PerlSAX passes the corresponding grove object as it's parameter so the properties passed to the handler are those that were used to create or were assigned to the grove. Please see the docs for the parser used to create the grove for a list of properties that were provided. =head2 DocumentHandler methods =over 4 =item start_document Receive notification of the beginning of a document. This is called from the XML::Grove::Document object before processing any document content. =item end_document Receive notification of the end of a document. This is called from the XML::Grove::Document object after processing all document content. =item start_element Receive notification of the beginning of an element. This is called from the XML::Grove::Element object before processing any element content. =item end_element Receive notification of the end of an element. This is called from the XML::Grove::Element object after processing all element content. =item characters Receive notification of character data. This is called from the XML::Grove::Characters object. =item processing_instruction Receive notification of a processing instruction. This is called from the XML::Grove::PI object. =item comment Receive notification of a comment. This is called from the XML::Grove::Comment object. =back =head1 AUTHOR Ken MacLeod, ken@bitsko.slc.ut.us =head1 SEE ALSO perl(1), XML::Grove(3) Extensible Markup Language (XML) =cut