Class: Zip::Deflater

Inherits:
Compressor show all
Defined in:
lib/zip/deflater.rb

Overview

:nodoc:all

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(output_stream, level = Zip.default_compression, encrypter = NullEncrypter.new) ⇒ Deflater

Returns a new instance of Deflater.



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# File 'lib/zip/deflater.rb', line 5

def initialize(output_stream, level = Zip.default_compression, encrypter = NullEncrypter.new)
  super()
  @output_stream = output_stream
  @zlib_deflater = ::Zlib::Deflate.new(level, -::Zlib::MAX_WBITS)
  @size          = 0
  @crc           = ::Zlib.crc32
  @encrypter     = encrypter
end

Instance Attribute Details

#crcObject (readonly)

Returns the value of attribute crc.



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# File 'lib/zip/deflater.rb', line 30

def crc
  @crc
end

#sizeObject (readonly)

Returns the value of attribute size.



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# File 'lib/zip/deflater.rb', line 30

def size
  @size
end

Instance Method Details

#<<(data) ⇒ Object



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# File 'lib/zip/deflater.rb', line 14

def <<(data)
  val   = data.to_s
  @crc  = Zlib.crc32(val, @crc)
  @size += val.bytesize
  buffer = @zlib_deflater.deflate(data, Zlib::SYNC_FLUSH)
  return @output_stream if buffer.empty?

  @output_stream << @encrypter.encrypt(buffer)
end

#finishObject



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# File 'lib/zip/deflater.rb', line 24

def finish
  buffer = @zlib_deflater.finish
  @output_stream << @encrypter.encrypt(buffer) unless buffer.empty?
  @zlib_deflater.close
end