序

本文主要研究一下rocketmq的DefaultRocketMQListenerContainer

DefaultRocketMQListenerContainer

rocketmq-spring-boot-2.0.3-sources.jar!/org/apache/rocketmq/spring/support/DefaultRocketMQListenerContainer.java

public class DefaultRocketMQListenerContainer implements InitializingBean,
    RocketMQListenerContainer, SmartLifecycle, ApplicationContextAware {
    private final static Logger log = LoggerFactory.getLogger(DefaultRocketMQListenerContainer.class);

    private ApplicationContext applicationContext;

    /**
     * The name of the DefaultRocketMQListenerContainer instance
     */
    private String name;

    private long suspendCurrentQueueTimeMillis = 1000;

    /**
     * Message consume retry strategy<br> -1,no retry,put into DLQ directly<br> 0,broker control retry frequency<br>
     * >0,client control retry frequency.
     */
    private int delayLevelWhenNextConsume = 0;

    private String nameServer;

    private AccessChannel accessChannel = AccessChannel.LOCAL;

    private String consumerGroup;

    private String topic;

    private int consumeThreadMax = 64;

    private String charset = "UTF-8";

    private ObjectMapper objectMapper;

    private RocketMQListener rocketMQListener;

    private RocketMQMessageListener rocketMQMessageListener;

    private DefaultMQPushConsumer consumer;

    private Class messageType;

    private boolean running;

    // The following properties came from @RocketMQMessageListener.
    private ConsumeMode consumeMode;
    private SelectorType selectorType;
    private String selectorExpression;
    private MessageModel messageModel;
    private long consumeTimeout;

    //......

    public void setRocketMQMessageListener(RocketMQMessageListener anno) {
        this.rocketMQMessageListener = anno;

        this.consumeMode = anno.consumeMode();
        this.consumeThreadMax = anno.consumeThreadMax();
        this.messageModel = anno.messageModel();
        this.selectorExpression = anno.selectorExpression();
        this.selectorType = anno.selectorType();
        this.consumeTimeout = anno.consumeTimeout();
    }

    @Override
    public void setupMessageListener(RocketMQListener rocketMQListener) {
        this.rocketMQListener = rocketMQListener;
    }

    @Override
    public void destroy() {
        this.setRunning(false);
        if (Objects.nonNull(consumer)) {
            consumer.shutdown();
        }
        log.info("container destroyed, {}", this.toString());
    }

    @Override
    public boolean isAutoStartup() {
        return true;
    }

    @Override
    public void stop(Runnable callback) {
        stop();
        callback.run();
    }

    @Override
    public void start() {
        if (this.isRunning()) {
            throw new IllegalStateException("container already running. " + this.toString());
        }

        try {
            consumer.start();
        } catch (MQClientException e) {
            throw new IllegalStateException("Failed to start RocketMQ push consumer", e);
        }
        this.setRunning(true);

        log.info("running container: {}", this.toString());
    }

    @Override
    public void stop() {
        if (this.isRunning()) {
            if (Objects.nonNull(consumer)) {
                consumer.shutdown();
            }
            setRunning(false);
        }
    }

    @Override
    public boolean isRunning() {
        return running;
    }

    private void setRunning(boolean running) {
        this.running = running;
    }

    @Override
    public int getPhase() {
        // Returning Integer.MAX_VALUE only suggests that
        // we will be the first bean to shutdown and last bean to start
        return Integer.MAX_VALUE;
    }


    @Override
    public void afterPropertiesSet() throws Exception {
        initRocketMQPushConsumer();

        this.messageType = getMessageType();
        log.debug("RocketMQ messageType: {}", messageType.getName());
    }

    @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        this.applicationContext = applicationContext;
    }

    @Override
    public String toString() {
        return "DefaultRocketMQListenerContainer{" +
            "consumerGroup='" + consumerGroup + '\'' +
            ", nameServer='" + nameServer + '\'' +
            ", topic='" + topic + '\'' +
            ", consumeMode=" + consumeMode +
            ", selectorType=" + selectorType +
            ", selectorExpression='" + selectorExpression + '\'' +
            ", messageModel=" + messageModel +
            '}';
    }

    private void initRocketMQPushConsumer() throws MQClientException {
        Assert.notNull(rocketMQListener, "Property 'rocketMQListener' is required");
        Assert.notNull(consumerGroup, "Property 'consumerGroup' is required");
        Assert.notNull(nameServer, "Property 'nameServer' is required");
        Assert.notNull(topic, "Property 'topic' is required");

        RPCHook rpcHook = RocketMQUtil.getRPCHookByAkSk(applicationContext.getEnvironment(),
            this.rocketMQMessageListener.accessKey(), this.rocketMQMessageListener.secretKey());
        boolean enableMsgTrace = rocketMQMessageListener.enableMsgTrace();
        if (Objects.nonNull(rpcHook)) {
            consumer = new DefaultMQPushConsumer(consumerGroup, rpcHook, new AllocateMessageQueueAveragely(),
                enableMsgTrace, this.applicationContext.getEnvironment().
                resolveRequiredPlaceholders(this.rocketMQMessageListener.customizedTraceTopic()));
            consumer.setVipChannelEnabled(false);
            consumer.setInstanceName(RocketMQUtil.getInstanceName(rpcHook, consumerGroup));
        } else {
            log.debug("Access-key or secret-key not configure in " + this + ".");
            consumer = new DefaultMQPushConsumer(consumerGroup, enableMsgTrace,
                    this.applicationContext.getEnvironment().
                    resolveRequiredPlaceholders(this.rocketMQMessageListener.customizedTraceTopic()));
        }

        String customizedNameServer = this.applicationContext.getEnvironment().resolveRequiredPlaceholders(this.rocketMQMessageListener.nameServer());
        if (customizedNameServer != null) {
            consumer.setNamesrvAddr(customizedNameServer);
        } else {
            consumer.setNamesrvAddr(nameServer);
        }
        if (accessChannel != null) {
            consumer.setAccessChannel(accessChannel);
        }
        consumer.setConsumeThreadMax(consumeThreadMax);
        if (consumeThreadMax < consumer.getConsumeThreadMin()) {
            consumer.setConsumeThreadMin(consumeThreadMax);
        }
        consumer.setConsumeTimeout(consumeTimeout);
        consumer.setInstanceName(this.name);

        switch (messageModel) {
            case BROADCASTING:
                consumer.setMessageModel(org.apache.rocketmq.common.protocol.heartbeat.MessageModel.BROADCASTING);
                break;
            case CLUSTERING:
                consumer.setMessageModel(org.apache.rocketmq.common.protocol.heartbeat.MessageModel.CLUSTERING);
                break;
            default:
                throw new IllegalArgumentException("Property 'messageModel' was wrong.");
        }

        switch (selectorType) {
            case TAG:
                consumer.subscribe(topic, selectorExpression);
                break;
            case SQL92:
                consumer.subscribe(topic, MessageSelector.bySql(selectorExpression));
                break;
            default:
                throw new IllegalArgumentException("Property 'selectorType' was wrong.");
        }

        switch (consumeMode) {
            case ORDERLY:
                consumer.setMessageListener(new DefaultMessageListenerOrderly());
                break;
            case CONCURRENTLY:
                consumer.setMessageListener(new DefaultMessageListenerConcurrently());
                break;
            default:
                throw new IllegalArgumentException("Property 'consumeMode' was wrong.");
        }

        if (rocketMQListener instanceof RocketMQPushConsumerLifecycleListener) {
            ((RocketMQPushConsumerLifecycleListener) rocketMQListener).prepareStart(consumer);
        }

    }

    private Class getMessageType() {
        Class<?> targetClass = AopProxyUtils.ultimateTargetClass(rocketMQListener);
        Type[] interfaces = targetClass.getGenericInterfaces();
        Class<?> superclass = targetClass.getSuperclass();
        while ((Objects.isNull(interfaces) || 0 == interfaces.length) && Objects.nonNull(superclass)) {
            interfaces = superclass.getGenericInterfaces();
            superclass = targetClass.getSuperclass();
        }
        if (Objects.nonNull(interfaces)) {
            for (Type type : interfaces) {
                if (type instanceof ParameterizedType) {
                    ParameterizedType parameterizedType = (ParameterizedType) type;
                    if (Objects.equals(parameterizedType.getRawType(), RocketMQListener.class)) {
                        Type[] actualTypeArguments = parameterizedType.getActualTypeArguments();
                        if (Objects.nonNull(actualTypeArguments) && actualTypeArguments.length > 0) {
                            return (Class) actualTypeArguments[0];
                        } else {
                            return Object.class;
                        }
                    }
                }
            }

            return Object.class;
        } else {
            return Object.class;
        }
    }

    //......
}

• DefaultRocketMQListenerContainer实现了InitializingBean, RocketMQListenerContainer, SmartLifecycle, ApplicationContextAware接口；setRocketMQMessageListener方法会根据RocketMQMessageListener注解的信息来设置consumeMode、consumeThreadMax、messageModel、selectorExpression、selectorType、consumeTimeout
• afterPropertiesSet方法执行了initRocketMQPushConsumer及getMessageType方法；initRocketMQPushConsumer方法会根据rpcHook是否为null来创建不同的DefaultMQPushConsumer，之后根据messageModel、selectorType、consumeMode等来配置consumer；如果rocketMQListener类型是RocketMQPushConsumerLifecycleListener的，则执行RocketMQPushConsumerLifecycleListener的prepareStart方法
• setupMessageListener方法主要是保存了rocketMQListener；isAutoStartup方法返回true；start方法主要是执行consumer.start()方法；stop及destroy方法主要是执行consumer.shutdown()

DefaultMessageListenerConcurrently

rocketmq-spring-boot-2.0.3-sources.jar!/org/apache/rocketmq/spring/support/DefaultRocketMQListenerContainer.java

    public class DefaultMessageListenerConcurrently implements MessageListenerConcurrently {

        @SuppressWarnings("unchecked")
        @Override
        public ConsumeConcurrentlyStatus consumeMessage(List<MessageExt> msgs, ConsumeConcurrentlyContext context) {
            for (MessageExt messageExt : msgs) {
                log.debug("received msg: {}", messageExt);
                try {
                    long now = System.currentTimeMillis();
                    rocketMQListener.onMessage(doConvertMessage(messageExt));
                    long costTime = System.currentTimeMillis() - now;
                    log.debug("consume {} cost: {} ms", messageExt.getMsgId(), costTime);
                } catch (Exception e) {
                    log.warn("consume message failed. messageExt:{}", messageExt, e);
                    context.setDelayLevelWhenNextConsume(delayLevelWhenNextConsume);
                    return ConsumeConcurrentlyStatus.RECONSUME_LATER;
                }
            }

            return ConsumeConcurrentlyStatus.CONSUME_SUCCESS;
        }
    }

• DefaultMessageListenerConcurrently方法实现了MessageListenerConcurrently接口；它的consumeMessage方法使用for循环try catch执行rocketMQListener.onMessage(doConvertMessage(messageExt))回调，都成功返回ConsumeConcurrentlyStatus.CONSUME_SUCCESS，一旦异常则返回ConsumeConcurrentlyStatus.RECONSUME_LATER

DefaultMessageListenerOrderly

rocketmq-spring-boot-2.0.3-sources.jar!/org/apache/rocketmq/spring/support/DefaultRocketMQListenerContainer.java

    public class DefaultMessageListenerOrderly implements MessageListenerOrderly {

        @SuppressWarnings("unchecked")
        @Override
        public ConsumeOrderlyStatus consumeMessage(List<MessageExt> msgs, ConsumeOrderlyContext context) {
            for (MessageExt messageExt : msgs) {
                log.debug("received msg: {}", messageExt);
                try {
                    long now = System.currentTimeMillis();
                    rocketMQListener.onMessage(doConvertMessage(messageExt));
                    long costTime = System.currentTimeMillis() - now;
                    log.info("consume {} cost: {} ms", messageExt.getMsgId(), costTime);
                } catch (Exception e) {
                    log.warn("consume message failed. messageExt:{}", messageExt, e);
                    context.setSuspendCurrentQueueTimeMillis(suspendCurrentQueueTimeMillis);
                    return ConsumeOrderlyStatus.SUSPEND_CURRENT_QUEUE_A_MOMENT;
                }
            }

            return ConsumeOrderlyStatus.SUCCESS;
        }
    }

• DefaultMessageListenerOrderly实现了MessageListenerOrderly接口，其consumeMessage方法使用for循环try catch执行rocketMQListener.onMessage(doConvertMessage(messageExt))回调，都成功返回ConsumeOrderlyStatus.SUCCESS，一旦异常则返回ConsumeOrderlyStatus.SUSPEND_CURRENT_QUEUE_A_MOMENT

小结

• DefaultRocketMQListenerContainer实现了InitializingBean, RocketMQListenerContainer, SmartLifecycle, ApplicationContextAware接口；setRocketMQMessageListener方法会根据RocketMQMessageListener注解的信息来设置consumeMode、consumeThreadMax、messageModel、selectorExpression、selectorType、consumeTimeout
• afterPropertiesSet方法执行了initRocketMQPushConsumer及getMessageType方法；initRocketMQPushConsumer方法会根据rpcHook是否为null来创建不同的DefaultMQPushConsumer，之后根据messageModel、selectorType、consumeMode等来配置consumer；如果rocketMQListener类型是RocketMQPushConsumerLifecycleListener的，则执行RocketMQPushConsumerLifecycleListener的prepareStart方法
• setupMessageListener方法主要是保存了rocketMQListener；isAutoStartup方法返回true；start方法主要是执行consumer.start()方法；stop及destroy方法主要是执行consumer.shutdown()

doc

• DefaultRocketMQListenerContainer