Class: Pdfrb::Source::ObjectReader

Inherits:
Object
  • Object
show all
Defined in:
lib/pdfrb/source/object_reader.rb

Overview

Resolves Model::Reference values to Model::Object instances by consulting the document's XrefSection. In-use entries seek and parse the indirect object at the recorded offset. Compressed entries defer to ObjectStreamReader.

Caches resolved objects per document.

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(document, xref) ⇒ ObjectReader

Returns a new instance of ObjectReader.



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# File 'lib/pdfrb/source/object_reader.rb', line 14

def initialize(document, xref)
  @document = document
  @xref = xref
  @cache = {}
  @objstm_cache = {}
end

Instance Attribute Details

#document ⇒ Object (readonly)

Returns the value of attribute document.



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# File 'lib/pdfrb/source/object_reader.rb', line 12

def document
  @document
end

#xref ⇒ Object (readonly)

Returns the value of attribute xref.



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# File 'lib/pdfrb/source/object_reader.rb', line 12

def xref
  @xref
end

Instance Method Details

#clear_cache ⇒ Object 



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# File 'lib/pdfrb/source/object_reader.rb', line 39

def clear_cache
  @cache.clear
  @objstm_cache.clear
end

#load(reference) ⇒ Object 



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# File 'lib/pdfrb/source/object_reader.rb', line 21

def load(reference)
  load_oid(reference.oid)
end

#load_oid(oid) ⇒ Object 



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# File 'lib/pdfrb/source/object_reader.rb', line 25

def load_oid(oid)
  return @cache[oid] if @cache.key?(oid)

  entry = xref[oid]
  return nil if entry.nil? || entry.free?

  obj = case entry.type
        when :in_use then parse_at(entry.offset, oid, entry.gen)
        when :compressed then load_from_objstm(entry.obj_stm_oid, entry.index, oid)
        end
  @cache[oid] = obj
  obj
end