require 'drb/drb' require 'monitor' module DRb class TimerIdConv < DRbIdConv class TimerHolder2 include MonitorMixin class InvalidIndexError < RuntimeError; end def initialize(timeout=600) super() @sentinel = Object.new @gc = {} @curr = {} @renew = {} @timeout = timeout @keeper = keeper end def add(obj) synchronize do key = obj.__id__ @curr[key] = obj return key end end def fetch(key, dv=@sentinel) synchronize do obj = peek(key) if obj == @sentinel return dv unless dv == @sentinel raise InvalidIndexError end @renew[key] = obj # KeepIt return obj end end def include?(key) synchronize do obj = peek(key) return false if obj == @sentinel true end end def peek(key) synchronize do return @curr.fetch(key, @renew.fetch(key, @gc.fetch(key, @sentinel))) end end private def alternate synchronize do @gc = @curr # GCed @curr = @renew @renew = {} end end def keeper Thread.new do loop do alternate sleep(@timeout) end end end end def initialize(timeout=600) @holder = TimerHolder2.new(timeout) end def to_obj(ref) return super if ref.nil? @holder.fetch(ref) rescue TimerHolder2::InvalidIndexError raise "invalid reference" end def to_id(obj) return @holder.add(obj) end end end # DRb.install_id_conv(TimerIdConv.new)