@Override
                public void operationComplete(ChannelFuture future) throws Exception {
                    if (future.isSuccess()) {
                        if (logger.isDebugEnabled()) {
                            logger.debug("Send heartbeat done! Id={}, to remoteAddr={}",
                                heartbeatId, RemotingUtil.parseRemoteAddress(ctx.channel()));
                        }
                    } else {
                        logger.error("Send heartbeat failed! Id={}, to remoteAddr={}", heartbeatId,
                            RemotingUtil.parseRemoteAddress(ctx.channel()));
                    }
                }
@see com.alipay.remoting.HeartbeatTrigger#heartbeatTriggered(io.netty.channel.ChannelHandlerContext)
src/main/java/com/alipay/remoting/rpc/protocol/RpcHeartbeatTrigger.java