How to use

IdleStateHandler$State

in

org.jboss.netty.handler.timeout

private static State state(ChannelHandlerContext ctx) {
  State state;
  synchronized (ctx) {
    // FIXME: It could have been better if there is setAttachmentIfAbsent().
    state = (State) ctx.getAttachment();
    if (state != null) {
      return state;
    }
    state = new State();
    ctx.setAttachment(state);
  }
  return state;
}