Class: CrossJoin

Inherits:
Join
  • Object
show all
Defined in:
lib/streaming_join/cross_join.rb

Instance Method Summary collapse

Methods inherited from Join

#initialize, #null_left, #null_right, #report

Constructor Details

This class inherits a constructor from Join

Instance Method Details

#output ⇒ Object 



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# File 'lib/streaming_join/cross_join.rb', line 4

def output
  left,right = @join

  left.each do |lk,lv|
    right.each do |rk,rv|
      o = "#{lk}#{@sep_out}#{lv}#{@sep_out}#{rk}#{@sep_out}#{rv}"
      if block_given?
        yield o
      else
        puts o
      end
    end
  end
end

#process_stream(input = STDIN, &blk) ⇒ Object 



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# File 'lib/streaming_join/cross_join.rb', line 19

def process_stream(input = STDIN, &blk)
  @join = [] # big memory, big prizes

  input.each do |line|
    key, side, value = line.chomp.split(@sep_in, 3)

    (@join[side.to_i] ||= []) << [key, value]
  end

  output(&blk) if not @join.empty?
end