com.github.cm.heclouds.adapter.mqttadapter.mqtt.MqttPingHandler Maven / Gradle / Ivy
package com.github.cm.heclouds.adapter.mqttadapter.mqtt;
import io.netty.channel.Channel;
import io.netty.channel.ChannelFutureListener;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInboundHandlerAdapter;
import io.netty.handler.codec.mqtt.MqttFixedHeader;
import io.netty.handler.codec.mqtt.MqttMessage;
import io.netty.handler.codec.mqtt.MqttMessageType;
import io.netty.handler.codec.mqtt.MqttQoS;
import io.netty.handler.timeout.IdleStateEvent;
import io.netty.util.ReferenceCountUtil;
import io.netty.util.concurrent.ScheduledFuture;
import java.util.concurrent.TimeUnit;
public class MqttPingHandler extends ChannelInboundHandlerAdapter {
private final int keepaliveSeconds;
private ScheduledFuture> pingRespTimeout;
public MqttPingHandler(int keepaliveSeconds) {
this.keepaliveSeconds = keepaliveSeconds;
}
@Override
public void channelRead(ChannelHandlerContext ctx, Object msg) {
if (!(msg instanceof MqttMessage)) {
ctx.fireChannelRead(msg);
return;
}
MqttMessage message = (MqttMessage) msg;
if (message.fixedHeader().messageType() == MqttMessageType.PINGREQ) {
this.handlePingReq(ctx.channel());
} else if (message.fixedHeader().messageType() == MqttMessageType.PINGRESP) {
this.handlePingResp();
} else {
ctx.fireChannelRead(ReferenceCountUtil.retain(msg));
}
}
@Override
public void userEventTriggered(ChannelHandlerContext ctx, Object evt) throws Exception {
super.userEventTriggered(ctx, evt);
if (evt instanceof IdleStateEvent) {
IdleStateEvent event = (IdleStateEvent) evt;
switch (event.state()) {
case WRITER_IDLE:
this.sendPingReq(ctx.channel());
break;
case READER_IDLE:
default:
break;
}
}
}
private void sendPingReq(Channel channel) {
MqttFixedHeader fixedHeader = new MqttFixedHeader(MqttMessageType.PINGREQ, false, MqttQoS.AT_MOST_ONCE, false, 0);
channel.writeAndFlush(new MqttMessage(fixedHeader));
if (this.pingRespTimeout != null) {
this.pingRespTimeout = channel.eventLoop().schedule(() -> {
MqttFixedHeader fixedHeader2 = new MqttFixedHeader(MqttMessageType.DISCONNECT, false, MqttQoS.AT_MOST_ONCE, false, 0);
channel.writeAndFlush(new MqttMessage(fixedHeader2)).addListener(ChannelFutureListener.CLOSE);
}, this.keepaliveSeconds, TimeUnit.SECONDS);
}
}
private void handlePingReq(Channel channel) {
MqttFixedHeader fixedHeader = new MqttFixedHeader(MqttMessageType.PINGRESP, false, MqttQoS.AT_MOST_ONCE, false, 0);
channel.writeAndFlush(new MqttMessage(fixedHeader));
}
private void handlePingResp() {
if (this.pingRespTimeout != null && !this.pingRespTimeout.isCancelled() && !this.pingRespTimeout.isDone()) {
this.pingRespTimeout.cancel(true);
this.pingRespTimeout = null;
}
}
}
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