Merge branch 'hone-gem'

extconf.rb

@@ -10,4 +10,17 @@
 EOF
 
 bindir = RbConfig::CONFIG['bindir']
-FileUtils.cp("mruby/build/x86_64-apple-darwin14/bin/mjruby", bindir)
+arch   = "#{ENV_JAVA['os.arch']}-#{ENV_JAVA['os.name']}"
+
+binary =
+  case arch
+  when /^(amd64|x86_64)-Linux/   then "mruby/build/x86_64-pc-linux-gnu/bin/mjruby"
+  when /^i\d86-Linux/            then "mruby/build/i686-pc-linux-gnu/bin/mjruby"
+  when /^x86_64-Mac OS X/        then "mruby/build/x86_64-apple-darwin14/bin/mjruby"
+  when /^i\d86-Mac OS X/         then "mruby/build/x86_64-apple-darwin14/bin/mjruby"
+  when /^x86-Windows/            then "mruby/build/i686-w64-mingw32/bin/mjruby"
+  when /^(amd64|x86_64)-Windows/ then "mruby/build/x86_64-w64-mingw32/bin/mjruby"
+  else nil
+    raise "Could not find appropriate architecture for '#{arch}'"
+  end
+FileUtils.cp(binary, bindir)