无法在 Camel 端点中设置 ActiveMQ 目标选项答案

【问题标题】：Cannot set ActiveMQ destination option in Camel endpoint无法在 Camel 端点中设置 ActiveMQ 目标选项
【发布时间】：2016-01-15 14:03:25
【问题描述】：

我正在尝试在 Camel JMS (ActiveMQ) 使用者上设置预取策略。根据 Camel 文档 http://camel.apache.org/activemq.html#ActiveMQ-UsingActiveMQDestinationOptions，我应该可以通过将 ?destination.consumer.prefetchSize=1 添加到端点 URL 来做到这一点。

不幸的是，当我这样做时，我得到以下异常

Caused by: org.apache.camel.ResolveEndpointFailedException: Failed to resolve endpoint: activemq://queue:ToSynchronize?destination.consumer.prefetchSize=1 due to: There are 1 parameters that couldn't be set on the endpoint. Check the uri if the parameters are spelt correctly and that they are properties of the endpoint. Unknown parameters=[{destination.consumer.prefetchSize=1}]
    at org.apache.camel.impl.DefaultComponent.validateParameters(DefaultComponent.java:183)
    at org.apache.camel.impl.DefaultComponent.createEndpoint(DefaultComponent.java:128)
    at org.apache.camel.impl.DefaultCamelContext.getEndpoint(DefaultCamelContext.java:558)
    ... 48 more

我有一个简单的路线构建器

@Component
public class IntegrationRout extends RouteBuilder {

    @Override
    public void configure() throws Exception {
        from("activemq:queue:ToSynchronize?destination.consumer.prefetchSize=1")
            .unmarshal().jaxb("com.foo.jms.model")
            .beanRef("Service", "upload")
    }
}

Java 中的 Spring 配置（取自一些关于如何配置 JMS 事务客户端的教程）

@Configuration
@EnableTransactionManagement
@ComponentScan(basePackages = {"com.foo"})
public class SynchronizationConfiguration extends CamelConfiguration {

    @Bean
    public ConnectionFactory jmsConnectionFactory() {
        return new ActiveMQConnectionFactory("tcp://localhost:61616");
    }

    @Bean
    @Autowired
    public PlatformTransactionManager jmsTransactionManager(final ConnectionFactory jmsConnectionFactory) {
        return new JmsTransactionManager(jmsConnectionFactory);
    }

    @Bean
    @Autowired
    public JmsComponent activemq(final ConnectionFactory jmsConnectionFactory, final PlatformTransactionManager jmsTransactionManager) {
        return JmsComponent.jmsComponentTransacted(jmsConnectionFactory, jmsTransactionManager);
    }
}

【问题讨论】：

标签： java spring jms apache-camel activemq

【解决方案1】：

如果配置像?destination.consumer.prefetchSize=1 这样的ActiveMQ 目标选项，您必须明确使用ActiveMQComponent 类。使用一般的JmsComponent 是行不通的。

所以你必须更换

    @Bean
    @Autowired
    public JmsComponent activemq(final ConnectionFactory jmsConnectionFactory, final PlatformTransactionManager jmsTransactionManager) {
        return JmsComponent.jmsComponentTransacted(jmsConnectionFactory, jmsTransactionManager);
    }

类似的东西

    @Bean
    @Autowired
    public JmsComponent activemq(final ConnectionFactory jmsConnectionFactory, final PlatformTransactionManager jmsTransactionManager) {
        final ActiveMQComponent activemq = new ActiveMQComponent();
        activemq.setConnectionFactory(jmsConnectionFactory);
        activemq.setTransactionManager(jmsTransactionManager);
        activemq.setTransacted(true);
        return activemq;
    }

【讨论】：