NAME

Data::Range::Compare::Stream::Iterator::Base - Abstract class

SYNOPSIS

package MyIterator;
use strict;
use warnings;
use IO::File;
use IO::Select;
use base qw(Data::Range::Compare::Stream::Iterator::Base);
use Data::Range::Compare::Stream;

sub new {
  my ($class,%args)=@_;
  my $has_next;
  my $self=$class->SUPER::new(%args);

  if(defined($args{filename})) {
    my $fh=IO::File->new($args{filename});
    if($fh) {
       $self->{fh}=$fh;
       my $line=$fh->getline;
       $self->{next_line}=$line;
       $has_next=defined($line);
    } else {
      $self->{msg}="Error could not open $args{filename} error was: $!";
    }

  }

  $self->{has_next}=$has_next;
  return $self;
}

sub get_next {
  my ($self)=@_;
  return undef unless $self->has_next;

  my $line=$self->{next_line};
  $self->{next_line}=$self->{fh}->getline;
  $self->{has_next}=$self->{next_line} ?  1 : 0;

  chomp $line;
  return new Data::Range::Compare::Stream(split /\s+/,$line);
}

1;

DESCRIPTION

This module acts as the base class for all Data::Range::Compare::Stream::Iterator classes.

Methods to implement

• my $iterator=new MyIterator(arguments=>here);

  The default object constructor takes a hash of arguments, and returns a blessed anonymous hash. If you want to do anything other than that you will need to overload this function!

• while($iterator->has_next) { do something }

  The internals return $self->{has_next}. If you want to do anything other than that you will need to overload this function!

• my $range=$iterator->get_next;

  Objects returned from this function should extend Data::Range::Compare::Stream::Result::Base

• my $string=$iterator->to_string;

  Returns the package name of $iterator

• $iterator->on_consolidate;

  This object needs to be called when ranges are being consolidated.

• $iterator->delete_from_root($id);

  Deletes $id from $iterator.

• if($iterator->is_child) { ... }

  Returns true if the object was auto generated by another object.

• if($iterator->has_child) { ... }

  Returns true if this $iterator auto generated a new iterator object

• my $id=$iterator->get_column_id

  Returns the column id of this $iterator.

• $iterator->set_column_id($id);

  Sets the column id of $iterator

• if($iterator->has_root) { ... }

  Returns true if this $iterator was auto generated by another iterator.

• my $root=$iterator->get_root;

  Returns the root object if $iterator->has_root is true.

• my $id=$iterator->get_root_column_id;

  Returns the column_id of the object that auto generated $iterator, returns current column_id of the object was not auto generated.

• my $child=$iterator->get_child;

  Returns the child object if $iterator->has_child is true.

• my $id=$iterator->get_child_column_id;

  Returns the child column_id if $iterator->has_child is true.

• my $line=$iterator->result_to_line($range);

  Given a $result from $iterator->get_next, this interface converts the $range object into a line that can be parsed by $iterator->parse_line($line). Think of this function as a data serializer for range objects generated by an $iterator object. When overloading this function or using a call back make sure result_to_line can be parsed by parse_line.

  sub result_to_line {
    my ($self,$result)=@_;
    return $self->{result_to_line}->($result) if defined($self->{result_to_line});
  
    my $range=$result->get_common;
    my $line=$range->range_start_to_string.' '.$range->range_end_to_string."\n";
    return $line;
  }

• my $ref=$iterator->parse_line($line);

  Given a $line returns the arguments required to construct an object that extends or implements Data::Range::Compare::Stream. When overloading or passing in constructor arguments that provide a call back make sure result_to_line produces the expected line parse_line expects.

  sub parse_line {
    my ($self,$line)=@_;
    return $self->{parse_line}->($line) if defined($self->{parse_line});
    chomp $line;
    [split /\s+/,$line];
  }

SEE ALSO

Data::Range::Compare::Stream::Cookbook

AUTHOR

Michael Shipper

Source-Forge Project

As of version 0.001 the Project has been moved to Source-Forge.net

Data Range Compare https://sourceforge.net/projects/data-range-comp/

COPYRIGHT

Copyright 2011 Michael Shipper. All rights reserved.

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.