javapluginversion64.rb

#!/usr/bin/ruby
#
#
# author: Eric Ohtake
#
# The custom fact fetches the Java Plugin 64 bits version currently installed on the system.
#
## Key for the version v8u65 HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Installer\Products\4EA42A62D9304AC4784BF2681408560F
## Key for the version v8u66 HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Installer\Products\4EA42A62D9304AC4784BF2681408660F

Facter.add("javaplugin64") do
  confine :kernel => :windows

  javaplugin64 = 'unknown'
  # This regex goes just before the 3 numbers given to the Java version/update
  regexp = "4EA42A62D9304AC4784BF2681408.*"

  begin

    if RUBY_PLATFORM.downcase.include?("mswin") or RUBY_PLATFORM.downcase.include?("mingw32")
      require 'win32/registry'
      # Opens the registry key, and uses the regex to match the root of the key.
      Win32::Registry::HKEY_LOCAL_MACHINE.open('SOFTWARE\\Classes\\Installer\\Products') do |version|
        version.each_key do | key |
          if /#{regexp}/ =~ key
            versionkey = key
            # Uses the key found above to open the values accordingly to the version.
            Win32::Registry::HKEY_LOCAL_MACHINE.open("SOFTWARE\\Classes\\Installer\\Products\\#{versionkey}") do |reg|
              reg.each do |name,type,data|
                if name.eql?("ProductName")
                  javaplugin64 = data
                end
              end
            end
          end
        end
      end
    end

  end

  setcode do
    javaplugin64
  end
end

http://ask.puppetlabs.com/question/22653/approach-update-java-plugin-on-windows/