Some more Jruby notes: compiled java classes vs ruby classes

ackerizer.rb

require 'rubygems'
require 'java'
require 'ackermann'
require 'benchmark'

time = Benchmark.measure do
  Ackermann.ack(3, 9)
end
puts "Ruby         :\t#{time}"


time = Benchmark.measure do
  Java::Ackermann.ack(3, 9)
end
puts "Compiled Java:\t#{time}"

Ackermann.java

public class Ackermann {
  public static int ack(int m, int n){
    if (m == 0){
      return n + 1;
    }

    if (n == 0){
      return ack(m - 1, 1);
    }

    return ack(m-1, ack(m, n-1));
  }
}

ackermann.rb

class Ackermann
  def self.ack(m, n)
    return n + 1 if m == 0
    return ack(m-1, 1) if n == 0
    return ack(m-1, ack(m, n-1))
  end
end

results.txt

joanne-chengs-MacBook-Pro-2:jruby-tests joannecheng$ jruby ackerizer.rb
Ruby         :	  0.730000   0.040000   0.770000 (  0.345000)
Compiled Java:	  0.050000   0.000000   0.050000 (  0.054000)