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我们正在尝试将 ActiveMQ 5.9.0 设置为使用 JMS 主题的消息代理，但我们在使用消息时遇到了一些问题。

出于测试目的，我们有 1 个主题、1 个事件生产者和 1 个消费者的简单配置。我们一个接一个地发送 10 条消息，但是每次运行应用程序时，其中 1-3 条消息没有被消费！其他消息被消费并处理得很好。我们可以在 ActiveMQ 管理控制台中看到我们发布到主题的所有消息，但它们永远不会到达消费者，即使我们重新启动应用程序（我们可以看到“入队”和“出队”列中的数字是不同的）。

编辑：我还应该提到，当使用队列而不是主题时，不会出现这个问题。

为什么会这样？它可能与atomikos（即事务管理器）有关吗？或者也许配置中的其他东西？欢迎任何想法/建议。:)

这是 ActiveMQ/JMS 弹簧配置：

    <bean id="connectionFactory" class="com.atomikos.jms.AtomikosConnectionFactoryBean"
    init-method="init" destroy-method="close">
    <property name="uniqueResourceName" value="amq" />
    <property name="xaConnectionFactory">
        <bean class="org.apache.activemq.spring.ActiveMQXAConnectionFactory"
            p:brokerURL="${activemq_url}" />
    </property>
    <property name="maxPoolSize" value="10" />
    <property name="localTransactionMode" value="false" />
</bean>

<bean id="cachedConnectionFactory"
    class="org.springframework.jms.connection.CachingConnectionFactory">
    <property name="targetConnectionFactory" ref="connectionFactory" />
</bean>

<!-- A JmsTemplate instance that uses the cached connection and destination -->
<bean id="jmsTemplate" class="org.springframework.jms.core.JmsTemplate">
    <property name="connectionFactory" ref="cachedConnectionFactory" />
    <property name="sessionTransacted" value="true" />
    <property name="pubSubDomain" value="true"/>
</bean>

<bean id="testTopic" class="org.apache.activemq.command.ActiveMQTopic">
    <constructor-arg value="test.topic" />
</bean>

<!-- The Spring message listener container configuration -->
<jms:listener-container destination-type="topic"
    connection-factory="connectionFactory" transaction-manager="transactionManager"
    acknowledge="transacted" concurrency="1">
    <jms:listener destination="test.topic" ref="testReceiver"
        method="receive" />
</jms:listener-container>

制作人：

@Component("producer")
public class EventProducer {

    @Autowired
    private JmsTemplate jmsTemplate;

    @Transactional
    public void produceEvent(String message) {
        this.jmsTemplate.convertAndSend("test.topic", message);
    }
}

消费者：

@Component("testReceiver")
public class EventListener {

    @Transactional
    public void receive(String message) {
        System.out.println(message);
    }  
}

考试：

    @Autowired
    private EventProducer eventProducer;

    public void testMessages() {

    for (int i = 1; i <= 10; i++) {
        this.eventProducer.produceEvent("message" + i);
    }
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1 回答 1

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That's the nature of JMS topics - only current subscribers receive messages by default. You have a race condition and are sending messages before the consumer has established its subscription, after the container is started. This is a common mistake with unit/integration tests with topics where you are sending and receiving in the same application.

With newer versions of Spring, there is a method you can poll to wait until the subscriber is established (since 3.1, I think). Or, you can just wait a little while before starting to send, or you can make your subscriptions durable.

于 2014-01-12T14:28:49.927 回答