Class: Origami::XRefStream

Inherits:
Stream
  • Object
show all
Includes:
Enumerable, StandardObject
Defined in:
lib/origami/xreftable.rb

Overview

Class representing a XRef Stream.

Constant Summary collapse

XREF_FREE = 
0
XREF_USED = 
1
XREF_COMPRESSED = 
2

Constants included from StandardObject

StandardObject::DEFAULT_ATTRIBUTES

Constants inherited from Stream

Stream::TOKENS

Constants included from Object

Object::TOKENS

Instance Attribute Summary

Attributes inherited from Stream

#dictionary

Attributes included from Object

#file_offset, #generation, #no, #objstm_offset, #parent

Instance Method Summary collapse

Methods included from StandardObject

#do_type_check, #has_field?, included, #set_default_value, #set_default_values, #version_required

Methods inherited from Stream

#[], #[]=, add_type_info, #cast_to, #data, #data=, #decode!, #each_filter, #each_key, #encode!, #encoded_data, #encoded_data=, #filters, guess_type, #key?, native_type, parse, #post_build, #set_predictor, #to_obfuscated_str, #to_s, #value

Methods included from Object

#<=>, #cast_to, #copy, #document, #export, #indirect?, #indirect_parent, #logicalize, #logicalize!, native_type, #native_type, parse, #post_build, #reference, #set_document, #set_indirect, skip_until_next_obj, #solve, #to_o, #to_s, #type, typeof, #version_required, #xrefs

Constructor Details

#initialize(data = "", dictionary = {}) ⇒ XRefStream

Returns a new instance of XRefStream.



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# File 'lib/origami/xreftable.rb', line 391

def initialize(data = "", dictionary = {})
    super(data, dictionary)

    @xrefs = nil
end

Dynamic Method Handling

This class handles dynamic methods through the method_missing method in the class Origami::Stream

Instance Method Details

#<<(xref) ⇒ Object

Adds an XRef to this Stream.



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# File 'lib/origami/xreftable.rb', line 420

def <<(xref)
    load! if @xrefs.nil?

    @xrefs << xref
end

#clear ⇒ Object 



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# File 'lib/origami/xreftable.rb', line 475

def clear
    self.data = ''
    @xrefs = []
    self.Index = []
end

#each(&b) ⇒ Object

Iterates over each XRef present in the stream.



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# File 'lib/origami/xreftable.rb', line 429

def each(&b)
    load! if @xrefs.nil?

    @xrefs.each(&b)
end

#each_with_number ⇒ Object

Iterates over each XRef present in the stream, passing the XRef and its object number.



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# File 'lib/origami/xreftable.rb', line 438

def each_with_number
    return enum_for(__method__) unless block_given?

    load! if @xrefs.nil?

    ranges = object_ranges
    xrefs = @xrefs.to_enum

    ranges.each do |range|
        range.each do |no|
            begin
                yield(xrefs.next, no)
            rescue StopIteration
                raise InvalidXRefStreamObjectError, "Range is bigger than number of entries"
            end
        end
    end
end

#entries ⇒ Object 



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# File 'lib/origami/xreftable.rb', line 397

def entries
    load! if @xrefs.nil?

    @xrefs
end

#find(no) ⇒ Object

Returns an XRef matching this object number.



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# File 'lib/origami/xreftable.rb', line 460

def find(no)
    load! if @xrefs.nil?

    ranges = object_ranges

    index = 0
    ranges.each do |range|
        return @xrefs[index + no - range.begin] if range.cover?(no)

        index += range.size
    end

    nil
end

#pre_build ⇒ Object

Returns XRef entries present in this stream.



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# File 'lib/origami/xreftable.rb', line 406

def pre_build #:nodoc:
    load! if @xrefs.nil?

    self.W = [ 1, 2, 2 ] unless has_field?(:W)
    self.Size = @xrefs.length + 1

    save!

    super
end