Class: Prawn::Core::ObjectStore
- Inherits:
-
Object
- Object
- Prawn::Core::ObjectStore
- Includes:
- Enumerable
- Defined in:
- lib/prawn/core/object_store.rb
Overview
:nodoc:
Constant Summary collapse
- BASE_OBJECTS =
%w[info pages root]
Instance Attribute Summary collapse
-
#min_version ⇒ Object
readonly
Returns the value of attribute min_version.
Instance Method Summary collapse
- #[](id) ⇒ Object
- #compact ⇒ Object
- #each ⇒ Object
-
#import_page(input, page_num) ⇒ Object
imports all objects required to render a page from another PDF.
- #info ⇒ Object
-
#initialize(opts = {}) ⇒ ObjectStore
constructor
A new instance of ObjectStore.
-
#object_id_for_page(k) ⇒ Object
returns the object ID for a particular page in the document.
- #page_count ⇒ Object
- #pages ⇒ Object
-
#push(*args, &block) ⇒ Object
(also: #<<)
Adds the given reference to the store and returns the reference object.
- #ref(data, &block) ⇒ Object
- #root ⇒ Object
- #size ⇒ Object (also: #length)
Constructor Details
#initialize(opts = {}) ⇒ ObjectStore
Returns a new instance of ObjectStore.
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# File 'lib/prawn/core/object_store.rb', line 21 def initialize(opts = {}) @objects = {} @identifiers = [] load_file(opts[:template]) if opts[:template] @info ||= ref(opts[:info] || {}).identifier @root ||= ref(:Type => :Catalog).identifier if pages.nil? root.data[:Pages] = ref(:Type => :Pages, :Count => 0, :Kids => []) end end |
Instance Attribute Details
#min_version ⇒ Object (readonly)
Returns the value of attribute min_version.
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# File 'lib/prawn/core/object_store.rb', line 17 def min_version @min_version end |
Instance Method Details
#[](id) ⇒ Object
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# File 'lib/prawn/core/object_store.rb', line 78 def [](id) @objects[id] end |
#compact ⇒ Object
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# File 'lib/prawn/core/object_store.rb', line 87 def compact # Clear live markers each { |o| o.live = false } # Recursively mark reachable objects live, starting from the roots # (the only objects referenced in the trailer) root.mark_live info.mark_live # Renumber live objects to eliminate gaps (shrink the xref table) if @objects.any?{ |_, o| !o.live } new_id = 1 new_objects = {} new_identifiers = [] each do |obj| if obj.live obj.identifier = new_id new_objects[new_id] = obj new_identifiers << new_id new_id += 1 end end @objects = new_objects @identifiers = new_identifiers end end |
#each ⇒ Object
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# File 'lib/prawn/core/object_store.rb', line 72 def each @identifiers.each do |id| yield @objects[id] end end |
#import_page(input, page_num) ⇒ Object
imports all objects required to render a page from another PDF. The objects are added to the current object store, but NOT linked anywhere.
The object ID of the root Page object is returned, it’s up to the calling code to link that into the document structure somewhere. If this isn’t done the imported objects will just be removed when the store is compacted.
Imports nothing and returns nil if the requested page number doesn’t exist. page_num is 1 indexed, so 1 indicates the first page.
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# File 'lib/prawn/core/object_store.rb', line 144 def import_page(input, page_num) @loaded_objects = {} io = if input.respond_to?(:seek) && input.respond_to?(:read) input elsif File.file?(input.to_s) if File.respond_to?(:binread) StringIO.new(File.binread(input.to_s)) else StringIO.new(File.read(input.to_s)) end else raise ArgumentError, "input must be an IO-like object or a filename" end # unless File.file?(filename) # raise ArgumentError, "#{filename} does not exist" # end hash = PDF::Reader::ObjectHash.new(io) ref = hash.page_references[page_num - 1] ref.nil? ? nil : load_object_graph(hash, ref).identifier rescue PDF::Reader::MalformedPDFError, PDF::Reader::InvalidObjectError msg = "Error reading template file. If you are sure it's a valid PDF, it may be a bug." raise Prawn::Errors::TemplateError, msg rescue PDF::Reader::UnsupportedFeatureError msg = "Template file contains unsupported PDF features" raise Prawn::Errors::TemplateError, msg end |
#info ⇒ Object
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# File 'lib/prawn/core/object_store.rb', line 38 def info @objects[@info] end |
#object_id_for_page(k) ⇒ Object
returns the object ID for a particular page in the document. Pages are indexed starting at 1 (not 0!).
object_id_for_page(1)
=> 5
object_id_for_page(10)
=> 87
object_id_for_page(-11)
=> 17
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# File 'lib/prawn/core/object_store.rb', line 126 def object_id_for_page(k) k -= 1 if k > 0 flat_page_ids = get_page_objects(pages).flatten flat_page_ids[k] end |
#page_count ⇒ Object
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# File 'lib/prawn/core/object_store.rb', line 50 def page_count pages.data[:Count] end |
#pages ⇒ Object
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# File 'lib/prawn/core/object_store.rb', line 46 def pages root.data[:Pages] end |
#push(*args, &block) ⇒ Object Also known as: <<
Adds the given reference to the store and returns the reference object. If the object provided is not a Prawn::Core::Reference, one is created from the arguments provided.
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# File 'lib/prawn/core/object_store.rb', line 58 def push(*args, &block) reference = if args.first.is_a?(Prawn::Core::Reference) args.first else Prawn::Core::Reference.new(*args, &block) end @objects[reference.identifier] = reference @identifiers << reference.identifier reference end |
#ref(data, &block) ⇒ Object
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# File 'lib/prawn/core/object_store.rb', line 34 def ref(data, &block) push(size + 1, data, &block) end |
#root ⇒ Object
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# File 'lib/prawn/core/object_store.rb', line 42 def root @objects[@root] end |
#size ⇒ Object Also known as: length
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# File 'lib/prawn/core/object_store.rb', line 82 def size @identifiers.size end |