Download Oracle JDK via Ruby

fetch_jdk.rb

require 'open-uri'
require 'open_uri_redirections'
require 'openssl'

def fetch(url, file, limit = 5)
  fail ArgumentError, "too many download failures from #{url}" if limit == 0
  load_open_uri_redirections
  uri = URI(url)
  begin
    open(uri,
         'Cookie' => 'oraclelicense=accept-securebackup-cookie',
         allow_redirections: :all,
         ssl_verify_mode: OpenSSL::SSL::VERIFY_NONE) do |fin|
      open(file, 'wb') do |fout|
        while (buf = fin.read(8192))
          fout.write buf
        end
      end
    end
  rescue
    fetch(url, file, limit - 1)
  end
end

fetch('https://download.oracle.com/otn-pub/java/jdk/8u51-b16/jdk-8u51-windows-x64.exe', '/tmp/jdk-8u51-windows-x64.exe')

Requires open_uri_redirections gem:

https://github.com/open-uri-redirections/open_uri_redirections