Crummy kind_of? or respond_to? benchmark under JRuby

gistfile1.rb

require 'java'
require 'benchmark'

s = Java::JavaLang::String.new('hello')

n = 10000000
respond_task = proc { n.times { s.respond_to?(:to_s) || abort('error') } }
no_respond_task = proc { n.times { s.respond_to?(:no_method) && abort('error') } }
kind_of_task = proc { n.times { s.kind_of?(Java::JavaLang::String) || abort('error') } }
no_kind_of_task = proc { n.times { s.kind_of?(Java::JavaLang::Integer) && abort('error') } }

tasks = {
  :respond => respond_task,
  :no_respond => no_respond_task,
  :kind_of => kind_of_task,
  :no_kind_of => no_kind_of_task
}

Benchmark.bm do |bm|

  puts "Warming up JRuby and JVM"

  # warmup jruby / jvm
  tasks.each do |name, task|
    bm.report("cold %10s:" % name, &task)
  end

  puts
  puts "Real test"

  tasks.each do |name, task|
    bm.report("warm %10s:" % name, &task)
  end
end

results

$ ruby bench_kind_of_require.rb 
      user     system      total        real
Warming up JRuby and JVM
cold    respond:  0.577000   0.000000   0.577000 (  0.547000)
cold no_respond:  0.475000   0.000000   0.475000 (  0.475000)
cold    kind_of:  0.639000   0.000000   0.639000 (  0.639000)
cold no_kind_of:  0.852000   0.000000   0.852000 (  0.852000)

Real test
warm    respond:  0.456000   0.000000   0.456000 (  0.456000)
warm no_respond:  0.505000   0.000000   0.505000 (  0.505000)
warm    kind_of:  0.564000   0.000000   0.564000 (  0.564000)
warm no_kind_of:  0.819000   0.000000   0.819000 (  0.818000)