class Formatter
def output_report( title, text )
raise 'Abstract method called'
end
end
class HTMLFormatter < Formatter
def output_report( title, text )
puts('')
puts(' ')
puts(" #{title} ")
puts(' ')
puts(' ')
text.each do |line|
puts(" #{line}
" )
end
puts(' ')
puts('')
end
end
class PlainTextFormatter < Formatter
def output_report(title, text)
puts("#{title}")
text.each do |line|
puts(line)
end
end
end
class Document
attr_reader :title, :text
attr_accessor :formatter
def initialize(formatter)
@title = 'Document'
@text = [ 'Things are going', ' well.' ]
@formatter = formatter
end
def output_report
@formatter.output_report( @title, @text )
end
end
report = Document.new(HTMLFormatter.new)
report.output_report
report.formatter = PlainTextFormatter.new
report.output_report