class Concurrent::Promises::AbstractEventFuture

def wait_until_resolved(timeout)
  return true if resolved?
  touch
  @Lock.synchronize do
    @Waiters.increment
    begin
      unless resolved?
        @Condition.wait @Lock, timeout
      end
    ensure
      # JRuby may raise ConcurrencyError
      @Waiters.decrement
    end
  end
  resolved?
end